This file is part of the TADS 2 Author's Manual.
Copyright © 1987 - 1996 by Michael J. Roberts.
All rights reserved.
The manual was converted to HTML by NK Guy, tela design.
The Text Adventure Development System (TADS)
Version file for Macintosh.
This file contains a list of changes that have been made to TADS since the initial 2.0 release. Most of the changes are fixes to bugs, so they don't change the documented behavior, but a few, as explained below, add new functionality to TADS. Releases are listed with the most recent release first; each release incorporates all new features and bug fixes of each prior release unless otherwise stated.
October 18 1996 - note from tela design.
Michael J. Roberts has in the past split the TADSVER file into two in order to keep it down to a manageable size. The first file covered changes from 2.0 through to 2.1.0; the second file covered all changes thereafter.
However, the TADSV200.xxx file appears to have vanished from the if-archive at ftp.ifarchive.org, leaving a rather large hole in the online TADS documentation. I've thus taken the liberty to combine the files I have to produce what I believe is the most complete version of the TADSVER documentation. For the Mac, anyway . This file differs slightly from the TADSVER.DOS and TADSVER.UNIX files.
- NK Guy (tela @ tela.bc.ca)
2.2.1.0 10/01/96 minor corrections, numbered object enhancement - Note that there has never been an "official" version 2.2.0.5; some versions with that designation have appeared on a few platforms to expedite the release of some bug fixes, but 2.2.0.5 was never universally released. To eliminate any confusion, this release is designated 2.2.1.0, and incorporates all of the bug fixes of and is upwardly compatible with any versions labeled 2.2.0.5. - The compiler, runtime, and debugger now create the swap file according to new rules intended to provide better support for multitasking and read-only media. In the past, if the user didn't specify a name for the swap file (through the appropriate "options" dialog), the system used TADSSWAP.DAT in the current directory; this was a problem when running two TADS games at once, since both games attempted to use the same default file, and when trying to run a game from a read-only disk (such as a CD-ROM). Now, the system uses the "Temporary Items" folder on the boot volume as the default location of the swap file, and attempts to choose a name for the file that isn't used by any other file. - The compiler and runtime use a slightly different method to pick the name of the .GAM file. First, if the name of the output file is specified to the compiler, the compiler does not attempt to add a .GAM extension to the file, unless the name matches the input file name exactly. Second, the run-time will first try to add a .GAM extension to the name of its input file, but if there is no such file, it will use the original name exactly as specified. These new rules are intended to make TADS more flexible on systems with long, unstructured filenames, such as the Macintosh or Windows 95, since it is often desirable to name files on these systems without using an extension in the DOS sense. - The player command parser has a new feature that allows you to use numbered objects without specifying in advance an object for each possible number. For example, if you want to design an elevator with 100 buttons for floors, you can now create a single button for all of the 100 buttons. The new feature uses a special new adjective property setting, '#'. For example: elevatorButton: fixeditem noun = 'button' plural = 'buttons' adjective = '#' location = elevator ; The special adjective '#' tells the parser that the object can be used with any number. The parser accepts the syntax "button 100" and "100 button" as equivalent, just as it would if you had specifically included '100' as an adjective with the object - in other words, the adjective '#' behaves the same way that regular numeric adjectives behave. When the player refers to the button in a command, the parser requires a number to be used. If the player refers to the button without a number, the parser displays error number 160, "You'll have to be more specific about which %s you mean" (where "%s" is replaced with the phrase the player entered that referred to the button). You can customize message 160 with parseError as with any other message. If the player properly enters a number with the object name (by typing, for example, "button 99"), the parser calls a new method in the object: newNumbered(actor, v, num) - "actor" is the actor for the command (Me if the command was not explicitly directed to another actor), "v" is the verb object, and "num" is a number typed by the player. "num" can also be nil: if the player refers to the button with a plural ("look at buttons"), the parser calls newNumbered with nil instead of a number to indicate that the player wants to refer to all such objects collectively. The newNumbered method must return either an object or nil. If it returns nil, the method should first display an error message - the parser will simply cancel the command without any further messages if newNumbered returns nil. If newNumbered returns an object, the parser uses this object (instead of the elevatorButton object itself) as the numbered object. adv.t includes a new class, numberedObject, that you can use to implement numbered objects. This class provides a newNumbered method that creates a copy of the object, and sets its value property to the number the player used to refer to the object - for example, if the player types "button 99," newNumbered will create a copy of the button, and the copy's "value" method will return the numeric value 99. The newNumbered method defined in numberedObject calls another method, num_is_valid(num), to determine if the number is valid; if this method returns true, newNumbered proceeds, otherwise it returns failure. By default, num_is_valid(num) returns true; you can override this method if you want to restrict the range of valid numbers. For example, you would define the elevator button's num_is_valid as follows: num_is_valid( num ) = { if ( num < 1 or num > 100 ) { "The buttons are numbered from 1 to 100."; return nil; } else return true; } The newNumbered method returns the original object by default if the player refers to the object with a plural; if you wish to use another object to handle plural references, override the method newNumberedPlural( actor, v ) to return a different object, or nil (after displaying an appropriate error message) if you don't want to allow plural references at all. You may want to handle plural references with a different object if you want plural references to work very differently - in other words, if you want actions taken on all such objects collectively to have special handling. The numberedObject defines dobjGen and iobjGen routines that don't allow any actions to be taken on the object in the plural; they do this by checking to see if the value property is nil, which indicates that this is the original (plural) object. These methods simply display "You'll have to be more specific about which one you mean" and otherwise ignore the command when the player uses the plural object. You may want to override this behavior for some verbs. For example, the elevator button's dobjGen should probably be defined like this: #pragma C+ dobjGen( a, v, i, p ) = { if ( self.value != nil or v != inspectVerb ) inherited.dobjGen( a, v, i, p ); else if ( v == inspectVerb ) { "The boxes are numbered 1000 to 9999."; exit; } } This allows the player to get some useful information from "look at buttons," but doesn't allow commands such as "push all buttons." Note that the implementation of newNumbered in numberedObject automatically sets a fuse to delete the newly created object at the end of the command. Therefore, you can't use the new objects to contain any state that you want to persist after the end of the command. For the elevator button example, the only thing you really need to remember is whether a particular button is lit up or not. You could do this with a list. When the game is first starting up, you could initialize this list like this: local i; elevator.button_list := []; for ( i = 1 ; i < 10 ; ++i ) elevator.button_list += [ nil nil nil nil nil nil nil nil nil nil ]; Now you can define the button's doPush method like this: doPush( actor ) = { if ( elevator.button_list[ value ] ) "It's already lit."; else elevator.button_list[ value ] := true; } The parser uses one additional method in some circumstances. When the player uses "any" with an object whose adjective list contains '#', the parser evaluates the property anyvalue(n) for the object. The parameter "n" is a number indicating how many of these objects has been requested so far for this command. Currently, it's always 1; in the future, a command such as "push any 3 buttons" may call this method three times, with "n" set to 1, 2, and 3, respectively, for the three calls. For the time being, "push any 3 buttons" is treated by the parser as identical with "push buttons". The default implementation of anyvalue in numberedObject in adv.t simply returns the same number "n" that it received as a parameter; if your valid number range doesn't start with 1, you should override this method to return a number in your object's valid range. - The compiler now generates more useful errors for undefined objects. In particular, errors for objects that are used in class lists but never defined now include the name of the undefined object and the source file location of the first use. In addition, the compiler now lists all undefined object errors with a line number prefix giving the actual line of the error, rather than providing that information parenthetically in the error message as it did formerly. In addition, the compiler now checks for undefined objects even when other errors are encountered, increasing the likelihood that you can find all errors on the first compile. - The player command parser now allows a word to start with a dash or apostrophe (these characters have always been allowed within words; now they're allowed at the starts of words, too). - The system allows format strings (such as %you%) to be used while the init() function is active, and uses Me as the current actor for translating the format strings. - Under certain circumstances, the compiler stored the same object/word relationship twice for a vocabulary word, causing the parser to list the same object more than once in a disambiguation question ("which book do you mean..."). This has been corrected. - The parser's handling of pronouns (it, him, her) has been changed slightly. Previously, the parser always replied "I don't know what you're referring to with 'it'" if the antecedant was not accessible for the new command (the validDo/validIo routine returned a false indication). The parser now instead uses the standard cantReach mechanism that would use if the command were typed with the object explicitly. - The runtime now calls preinit() prior to calling the restart callback function if one was provided and the game was compiled for debugging. (The runtime previously called preinit() *after* calling the restart callback when the game was compiled for debugging, which meant that the game state as seen in the callback was different when a game was compiled for debugging than for the same game compiled with debugging off, because with debugging off, preinit is run by the compiler. This change makes the state seen by the restart callback function the same for both versions of the game.) - The Mac run-time now enables the Undo item on the Edit menu; selecting this menu item sends the command UNDO to the game, which (for most games) takes back the most recent command. - Assignments through property pointers now work properly. 2.2.0 10/30/94 new features, enhancements, bug fixes - TADS now has support for reading and writing files. This new feature is intended to let you save information independently of the game-saving mechanism, which allows you to transfer information between sessions of a game, or even between two different games. The TADS file operations are not designed as general-purpose file system operations; in particular, these new functions don't have any provisions for creating or reading formatted files, or for exchanging information with programs other than TADS games. To open a file, use the fopen() function. This function takes two arguments: a single-quoted string giving the name of the file to open, using local file system conventions, and a "mode." (For maximum portability, you should avoid using volume names, directories, folders, or other path information in filenames.) The mode argument is one of these single-quoted string values: r open file for reading; file must already exist r+ open file for reading and writing; the file is created if it doesn't already exist w create a new file for writing; the file is deleted if it already exists w+ create a new file for reading and writing; the file is deleted if it already exists The return value of fopen() is a "file handle"; this is simply a number that you you to perform subsequent operations on the file. For example, this opens a new file called TEST.OUT for writing: fnum := fopen( 'test.out', 'w' ); To close an open file, use fclose(): fclose( fnum ); Note that the TADS runtime allows only a limited number of files (currently 10) to be open simultaneously, so you should close a file when you're done with it. To write to a file, use fwrite(). This function takes a file handle, and a value to write; the value can be a string, a number, or true. The value can't be nil (this is because the fread() function returns nil to indicate failure; if you could write nil to a file, there would be no way to distinguish reading a valid nil from an error condition). fwrite() stores the value, along with information on its type. The fwrite() function returns nil on success, true on failure. If the function returns true, it usually means that the disk is full. if ( fwrite( fnum, 'string value!' ) or fwrite( fnum, 123 ) ) "Error writing file!"; If the file is open for reading, you can read from the file with the fread() function. This function takes a file handle, and it returns a value it reads from the file. The value returned is of the same type as the value originally written at this position in the file with fwrite(). If this function returns nil, it indicates that an error occurred; this usually means that no more information is in the file (you've read past the end of the file). res := fread( fnum ); say( res ); You can get the current byte position in the file with the ftell() function: "The current seek position is << ftell(fnum) >>. "; The ftell() function returns a number giving the byte position that will be read or written by the next file operation. You can set the file position with fseek() and fseekeof(). The fseek() function moves the file position to a particular byte position, relative to the beginning of the file. For example, this seeks to the very beginning of a file: fseek( fnum, 0 ); The fseekeof() function positions the file at its end: fseekeof( fnum ); Note that you must be careful with fseek(). You should only seek to positions that you obtained with the ftell() function; other positions may be in the middle of a string or a number in the file, so seeking to an arbitrary location and writing could render the file unusable by partially overwriting existing data. - You can now "capture" displayed text to a string. This new feature allows you to examine and manipulate text displays, no matter how they are generated. To activate capturing, use the new built-in function outcapture(): stat := outcapture( true ); This starts capturing text. The return value is a status code that you use in the subsequent call to end capturing; you don't need to do anything with this status code except pass it to outcapture() when you're finished capturing output. While capturing is in effect, everything that your game attempts to display - through double-quoted strings or through the say() built-in function - is hidden from the user and instead stored in a string. Once outcapture(true) is called, no text will be displayed to the user until you call this function: str := outcapture( stat ); The second outcapture() call turns off capturing, and returns a string that contains all of the text that was generated since the corresponding outcapture(true). Note that the system automatically turns off capturing any time it prompts the user for information. The system turns off capturing when it starts a new command, or when it needs to prompt the user for information during a command, such as for disambiguation or to request a missing direct or indirect object. When the system turns off output capturing, it clears the capture buffer, so any subsequent call to outcapture(stat) will return an empty string. You can capture text only over the course of a single command line. The outcapture() function can be useful if you want to save some text for later. It's also useful if you want to be able to examine the text that would be generated by a method such as sdesc or ldesc. Since these methods directly display text, you can't directly obtain a string representation of their values; using outcapture(), however, you can let them "display" their values into a string that you can then examine. Note that the status value returned from outcapture(true) allows you to nest calls to outcapture(). Since the outcapture(stat) call restores the capturing status that was in effect on the corresponding call to outcapture(true), you don't have to worry when using outcapture() about whether any of the methods you're calling are also using it. - TADS now allows you to create and delete objects dynamically at run-time. This is done through two new operators: "new" and "delete". To create a new object, use this syntax: x := new bookItem; This dynamically creates a new object whose superclass is bookItem. When this statement is executed, the runtime creates a new object, assigns its superclass to be bookItem, and executes the "construct" method in the new object; this method can perform any creation-time setup that's desired. The default thing.construct in adv.t simply moves the new object into its location - this is necessary so that the "contents" list of the location is updated to include the new object. A new object inherits all of the vocabulary of its superclass. To destroy an object you have created, use this syntax: delete x; This first calls the "destruct" method of the object to notify it that it is about to be deleted, then destroys the object. Further references to the object are illegal, since its memory has been released (and thus may be given to another object). The default thing.destruct in adv.t moves the object into nil, which removes it from its container's "contents" list - this is necessary so that the reference to the object in that list is removed. Only objects created with "new" can be destroyed with "delete". Objects that are defined statically in your game's source file cannot be deleted at run-time. Object creation and deletion works correctly with the UNDO mechanism. If the player uses UNDO after a move that created an object, the object will be destroyed; likewise, if a player uses UNDO after a turn that deletes an object, the object will be re-created with the same property values it had prior to deletion. Similarly, dynamically-created objects are preserved across SAVE and RESTORE operations. Note that TADS does not perform any garbage collection on dynamically-created objects. The system is not capable of determining whether an object is accessible or not. Hence, if you lose track of any objects you create with "new", they will remain in memory forever - they will even be saved along with saved games and restored when the games are restored. You must be careful to keep track of all objects you create to avoid filling all available memory (and the swap file) with unreachable objects. - It is now possible to dynamically add to and delete from the vocabulary words of an object. You can also get the vocabulary words of an object at run-time. To add to an object's vocabulary, use the new "addword" built-in function. This function takes three arguments: an object, a vocabulary property pointer, and a word to add. For example, to add 'red' as an adjective to the object myBook, you would do this: addword( myBook, &adjective, 'red' ); To delete the same word, you would write a similar call to the new built-in function "delword": delword( myBook, &adjective, 'red' ); You can add to and delete from the words of any object, including both static objects (explicitly defined in your source code) and dynamically-created objects (created with the "new" operator). Changes made by addword and delword are tracked correctly by the UNDO mechanism, and are saved and restored along with saved games. To get the words belonging to an object, use the new "getwords" built-in function. This function takes two arguments: an object, and a property pointer; it returns a list of (single-quoted) strings, which are the vocabulary words for the object. For example, assume we define myBook as follows: myBook: item sdesc = "small red book" adjective = 'small' 'red' 'tiny' noun = 'book' location = room2 ; Also assume we haven't made any calls to addword() or delword() for myBook. In this case, getwords( myBook, &adjective ) would return this list: [ 'small' 'red' 'tiny' ] Note that the order of the words in the list is not predictable, so you shouldn't expect the words to be in the same order as they were when you defined them in the source file, or in the same order as they were added with addword(). - We've added a new function that lets you get information on a verb. The new function is verbinfo(). This function lets you get the verification and action properties for a verb. The new function takes one or two arguments: the first is the deepverb object whose information you want to retrieve; the optional second argument is a preposition object. If you call verbinfo() with only the verb argument, it returns the verification and action properties that are defined with the doAction definition for the verb. If you also include the preposition argument, it returns the properties that are defined with the ioAction definition for that preposition. The value returned by this function is a list. If you call verbinfo() with only the deepverb argument, the list has two elements: [1] direct object verification property pointer (verDoXxxx) [2] direct object action property pointer (doXxxx) If you call verbinfo() with both the verb and preposition arguments, the return value is a list with four elements: [1] direct object verification property pointer (verDoXxxx) [2] indirect object verification property pointer (verIoXxxx) [3] indirect object action property pointer (ioXxxx) [4] true if ioAction has [disambigDobjFirst] flag, nil otherwise In either case, if no matching doAction or ioAction definition exists for the verb, this function returns nil. Note that it is possible that additional flags (similar to disambigDobjFirst) may be added in the future; the returned list may be expanded to include information on any such added flags. So, for compatibility with future versions, we recommend that you don't write conditional code based on the length of the list. The lists will never shrink, but they may expand. For the removeVerb object defined in adv.t, you would get these results: verbinfo(removeVerb) = [ &verDoUnwear &doUnwear ] verbinfo(removeVerb, fromPrep) = [ &verDoRemoveFrom &verIoRemoveFrom &ioRemoveFrom nil ] - The ability to create new objects at run-time leads to some interesting problems involving indistinguishable objects. Although you should generally use addword (see below) to make your newly-created objects distinguishable from one another, this will not always be desirable; for example, if you create new gold pieces that serve as currency, you will probably not want them to be uniquely named. To support indistinguishable objects, especially those created dynamically at run-time, the system now has a property that you can set to indicate to the parser that an object does not need to be distinguished from others of the same class. The new property is "isEquivalent". When isEquivalent returns true for an object, all other objects with the same immediate superclass are considered interchangeable by the parser. When a player uses one of these objects in a command, the parser will simply pick one arbitrarily and use it, without asking the player which one. If a player uses a noun that is ambiguous with multiple equivalent items and one or more other items, the parser will need to disambiguate the objects as usual. In such cases, the parser's question will list the distinguishable items only once. For example, assume we have five gold coins that are all equivalent (in other words, they all have isEquivalent set to true, and they all are immediate subclasses of the same class). Assume further that a silver coin and a bronze coin are also present in the room. Treasure Room You see a bronze coin, five gold coins, and a silver coin here. >get coin Which coin do you mean, the bronze coin, a gold coin, or the silver coin? Note that the objects which appear only once are listed with "the" (using the thedesc property), while the indistinguishable objects are listed only once, with "a" (using the adesc property). - The new property pluraldesc has been added to thing in adv.t. The definition in thing simply adds an "s" to the end of the sdesc property. This new property is used by listcont(obj) when multiple equivalent objects are present in a list; see the information on the changes to listcont(obj) for details. - The adv.t functions listcont(obj) and itemcnt(list) have been changed to support indistinguishable objects. To support this new functionality, the new functions isIndistinguishable(obj1, obj2) and sayPrefixCount(cnt), and the new property pluraldesc, have been added to adv.t. isIndistinguishable(obj1, obj2) returns true if the two objects obj1 and obj2 are equivalent for the purposes of listing. The two objects are considered equivalent if both have the same first superclass (the return value of the new built-in function firstsc(obj)), either they are both being worn or neither is worn, and either both are lit lightsources or neither is. This function doesn't test the isEquivalent property of either object, since it's assumed that it will only be called if an object has already been found whose isEquivalent property is set. sayPrefixCount(cnt) displays a number. If the parameter cnt is a small number (from one to twenty), the spelled-out number will be displayed (for example, "five" will displayed if cnt = 5). If the count is larger, the number will be displayed as digits ("35" will be displayed if cnt = 35). This function is used by listcont(obj) to show the number of equivalent items when more than one equivalent item is being listed. itemcnt(list) now returns the number of distinguishable items in the list that are to be listed. For each item in the list whose isEquivalent property is true, itemcnt(list) checks each other item in the list, and counts each set of equivalent items only once. Hence, if a list consists entirely of equivalent items, itemcnt(list) will return at most 1 (it will return 0 if none of the items are listable). listcont(obj) will list each set of indistinguishable items in the contents list only once, and will show the number of each such item. To display the number, the new function sayPrefixCount(cnt) is used. For example, if a room contains a silver coin, a bronze coin, and five gold coins (all with the isListed property set to true), listcont(room) will display this: a silver coin, a bronze coin, and five gold coins - A new built-in function has been added to make it possible to implement the functionality of the new listcont method. The new function, firstsc(obj), returns the first immediate superclass of the given object (or nil if the object has no superclass). This function, along with the isEquivalent property, can be used to determine if two objects should be considered indistinguishable. - A new special word has been added: ANY, which is equivalent to EITHER. These words are at the end of the original specialWords list; for compatibility with past versions, a specialWords list that omits this position is still legal, and indicates that the default ('any' = 'either') should be used for this slot. This special word slot is used by the parser during disambiguation. Whenever the parser asks the player to choose an object from a list of ambiguous objects, it will accept ANY: >take coin Which coin do you mean, the silver coin, the bronze coin, or the gold coin? >any silver coin: Taken. When ANY is used in these cases, the parser will simply pick one of the objects arbitrarily. Note that it displays the chosen object in the same manner as it would if multiple objects were being used. In addition, the parser will accept noun phrases that start with ANY to indicate that any object matching the given noun phrase is acceptable; the parser will choose one of the objects arbitrarily in these cases. For example: >take any coin silver coin: Taken. >look at any of the coins bronze coin: It's a valuable 1964 Tadsmid, worth over .0004 cents on today's scrap bronze market. The player can also specify the number of items to take. When a number of items is specified, it must be applied to a plural noun phrase, and it means the same thing as "any," except that the parser (arbitrarily) chooses the given number of items rather than just one. For example: >look at 3 coins >look at any 3 coins >look at 3 of the coins >look at any 3 of the coins As a special case, a count of "1" can be used with a singular noun phrase. It means the same thing as "any." >look at 1 coin - A new convenience feature, similar to doSynonym and ioSynonym but somewhat easier to use, has been added. You can now specify that a method in one object should instead be sent to another object. An example: desk: fixeditem noun = 'desk' sdesc = "desk" location = office doOpen -> deskDrawer doClose -> deskDrawer ; This specifies that doOpen, verDoOpen, doClose, and verDoClose calls should be sent to the deskDrawer object when received by the desk. Note that this should only be used for standard verb handler methods, because it redirects both the method indicated and its verXoVerb equivalent. - The parser calls a new method, multisdesc, when displaying the name of an object that's part of a list of objects. Previously, the parser simply used sdesc in these cases. The default adv.t definition of thing.multisdesc simply calls the object's sdesc. This new method is intended to allow you greater control over the display in situations like this: >get all book: Taken. rug: That's much too heavy to carry. The object names listed before the colons are now displayed with multisdesc. For compatibility with old games, if an object being listed does not define or inherit a multisdesc property, its sdesc is used instead. This ensures that games compiled with previous versions of adv.t will continue working properly. - A new user-defined function that the parser calls has been added. This new function is called preparseCmd(), and is similar to preparse(). Whereas preparse() is called once for an entire command line, and is called with the original, unfiltered text of the player's command line, preparseCmd() is called separately for each command on a command line if more then one command is entered. Furthermore, preparseCmd() is called after the command has been "tokenized" (broken into individual words). Whereas the argument to preparse() is a string with the entire command line, the argument to preparseCmd() is a list, each entry of which is a (single-quoted) string giving an individual word. Using the new function, you can exert much greater control over how a command is parsed, including rewriting a command entirely. preparseCmd() is called immediately before Me.roomCheck() is called for the command. This call is made prior to any disambiguation or object defaulting. If preparseCmd() returns nil, the command is abandoned (but no error message is displayed), and no fuses or daemons are run. If the function returns true, the command proceeds as normal. Any remaining commands on the same line are executed regardless of the return value from preparseCmd(). (If you need to cancel the entire rest of the command line, one approach would be to set a property in the global object to indicate to preparseCmd() that all commands are to be ignored; preparseCmd() would always check this property before doing anything else, and return nil if it were set. You could clear this property in preparse() so that commands always start off enabled.) In addition, preparseCmd() can return a list of (single-quoted) strings, in which case the parser starts over parsing the list instead of the original command. The list is limited to a maximum of 128 characters, with one additional character of overhead per word - in other words, you can't make the new command longer than the original command, which is limited to the same maximum when entered by the player in the first place. However, you can otherwise rewrite the command entirely. If you want to include any special words in the new command, use the conventions described below (for example, if you want to include 'and' in the new command, use ',' instead). After the new command inserted by preparseCmd() has been processed, the parser will resume processing any remaining commands on the player's original command line. The new command list returned by preparseCmd() can contain multiple commands. Simply separate the commands with commas (',') in your list. If preparseCmd() returns a list, preparseCmd() will be invoked on the new command. However, preparseCmd() is not allowed to return another new command in these cases - if it does, the parser will assume that preparseCmd() is looping, and will generate an error. Several new parseError codes have been added to respond to error conditions that can arise from preparseCmd(): 32 Internal game error: preparseCmd returned an invalid list 33 Internal game error: preparseCmd command too long 34 Internal game error: preparseCmd loop The sample implementation of preparseCmd() below simply lists all of the words in the current command and displays a newline, then allows the command to proceed as usual. #pragma C+ preparseCmd: function( cmd ) { local i, tot; for ( i = 1, tot = length( cmd ) ; i <= tot ; ++i ) "<<cmd[ i ]>> "; "\n"; return true; } Note that the parser performs conversions of the special words. These conversions will show up in the list as follows: "and" becomes "," "all" becomes "A" "but" becomes "X" "it" becomes "I" "them" becomes "T" "him" becomes "M" "her" becomes "R" "any" becomes "Y" Here are some examples using the preparseCmd() function above. (The actual response of the commands has been removed - only the text displayed by preparseCmd() is shown.) >look at all look at A >examine him; take everything except the box and the book and go north examine M take A X the box , the book go north preparseCmd() is called even for commands that the parser doesn't understand. This allows you to rewrite commands that TADS wouldn't normally understand and put them into a format that's acceptable to the parser. For example, the preparseCmd() example below will take sentences of the form "tell <actor> to <command>", and convert them to the normal TADS syntax, "<actor>, <command>". #pragma C+ preparseCmd: function( cmd ) { local i, tot, to_loc, actor, the_rest; tot = length( cmd ); /* check to see if it starts with "tell" */ if ( tot > 3 && cmd[ 1 ] == 'tell' ) { /* see if there's a word "to" */ for ( i = 1, tot = length(cmd) ; i <= tot ; ++i ) { if ( cmd[ i ] == 'to' ) to_loc = i; } /* if there's a "to", convert the command */ if ( to_loc != nil && to_loc > 2 ) { /* find the parts before and after the 'to' */ for ( i = 2, actor = [] ; i < to_loc ; ++i ) actor += cmd[i]; for ( the_rest = [], i = to_loc + 1 ; i <= tot ; ++i ) the_rest += cmd[ i ]; /* convert it to "actor, command" */ return actor + ',' + the_rest; } } /* otherwise, process the command as normal */ return true; } When the parser doesn't know how to handle a sentence, it calls preparseCmd with the entire rest of the command (which will include everything before the next THEN or period), and processing is the same as in any other case. If preparseCmd() returns nil in this case, the command is cancelled as usual without any further processing by the parser. If preparseCmd() returns true when the sentence is not recognized by TADS, the parser will display the usual message (parseError code 18, "I don't understand that sentence"). If preparseCmd() returns a list of strings, the command is replaced with the list, and the parser starts over processing the new command. - Several new parseError codes have been added. In order to produce better messages when actors are involved, the system now attempts to figure out whether an object in a command refers to an actor, and if so, to determine whether the actor should be called "him" or "her". Previously, this one-size-fits-all message was generated: What do you want to <verb> it <prep>? for example: >hit bill What do you want to hit it with? Although it's not always possible to determine which object should be used in these cases (because disambiguation will not be possible until the indirect object is known), the system will make its best guess. To do so, it looks at all of the objects that might be involved, based on the vocabulary. If the player appears to mean multiple objects, " them " will be used - this is message number 144 for parseError: >throw ball and bat What do you want to throw them at? <- message 144 ------ If only one object appears to be intended, the parser will try to figure out whether the object is male, female, or neuter, using the isHim and isHer properties (these properties are not new; they have been around since before TADS 2.0). If all of the objects that match a single noun phrase have isHim and not isHer, " him " will be used - this is parseError message number 145: >hit bill What do you want to hit him with? <- message 145 ----- If they all have isHer and not isHim, " her " will be used (message number 146): >hit jill What do you want to hit her with? <- message 146 ----- If both are set, the system equivocates with " them ", message number 147 (note that this is the same default text as message 144, but it's distinguished as a separate message number in case a game author wants a more suitable word in this case, especially in a non-English language): >hit hermaphrodite What do you want to hit them with? <- message 147 ------ If not all of the objects involved have isHim and/or isHer set, the system uses "it" (message 141) as in previous versions. Another change to the processing for this message involves actors. If an actor is specified in the command, the system now builds a replacement for message 140. First, message 148 is displayed, which has the default text "What do you want ". Then, the actor's thedesc is invoked to display the actor's name. Finally, message 149 (default text " to ") is displayed, and the rest of the message is built as before. >guard, throw ball What do you want the guard to throw it at? ----------------- ---- message 148 149 - The functionality of the parseAskobj function has been extended so that you can generate the same sort of message that the parser now generates when a missing object is needed for a command directed to an actor. To provide the new functionality, the parser now calls a function called parseAskobjActor. This function is exactly the same as parseAskobj, except that it takes the actor as the first parameter, the verb as the second parameter, and the preposition as an optional third parameter (which is only present when asking for an indirect object). If your game defines parseAskobjActor, the system ignores parseAskobj and calls the new function instead. If parseAskobjActor is not defined, but parseAskobj is defined, the system calls parseAskobj as it did in past versions. If neither function is defined, the system generates the message itself as described above. You should use parseAskobjActor rather than parseAskobj for new games, since it gives you more information. Here's an example of parseAskobjActor, which generates roughly the same message as the system would (but it doesn't do any of the checking of isHim and isHer to determine which pronoun to use - this function simply uses "it"). #pragma C+ parseAskobjActor: function( a, v, ... ) { if ( argcount == 3 ) { "What do you want "; if ( a != Me ) a.thedesc; " to <<v.sdesc>> it <<getarg(3).sdesc>>?"; } else { "What do you want "; if ( a != Me ) a.thedesc; " to <<v.sdesc>>?"; } } - The parser has been changed slightly to allow a command to specify an actor in any command within a single line containing multiple commands. Previously, if an actor was to be specified, the actor had to be specified at the very beginning of the command. This restriction has been removed, which allows commands like this: >joe, north. bob, south. bill, east, take book, west. Note that, as in past versions, once an actor is specified, the actor remains in effect for subsequent commands. Since you could only specify one actor for an entire command line in past versions, this meant that the actor was used for every command on the line; with this new version, an actor remains in effect until another actor is specified. So, in the command above, "north" is directed to Joe, "south" is directed to Bob, and "east, take book, west" is directed to Bill. - The maximum number of notifiers has been increased to 200. The maximum number of daemons and fuses has been increased to 100 each. - The maximum number of ambiguous words matching a particular vocabulary word has been increased to 200. This should relieve problems that some people have reported with the error message "The word 'foo' refers to too many objects". - The compiler now supports most of the remaining C operators: a % b - returns the remainder of dividing a by b a %= b - sets a to a % b a != b - equivalent to a <> b !a - equivalent to (not a) a & b - bitwise AND a &= b - sets a to the bitwise AND of a and b a | b - bitwise OR a |= b - sets a to the bitwise OR of a and b a && b - equivalent to (a and b) a || b - equivalent to (a or b) a ^ b - bitwise XOR of a and b a ^= b - sets a to the bitwise XOR of a and b ~a - bitwise negation of a a << b - a shifted left by b bits a <<= b - shifts a left by b bits a >> b - a shifted right by b bits a >>= b - shifts a right by b bits Note a slight complication involving the >> operator: you can't use this operator from within an embedded string expression, because it would be confused by the parser for the end of the expression. It doesn't help to use parentheses, since the embedded string processing is essentially a textual substitution mechanism which happens without knowledge of the expression context (and is thus unaware of parenthesization). For example, this would be illegal: myprop = "x divided by 128 is << (x >> 7) >>! " // wrong You would have to code this instead as: myprop = { "x divided by 128 is "; x >> 7; "! "; } // right Another slight complication arises from the use of the & operator in lists. Since TADS allows list elements to appear without any separating punctuation (except whitespace), you can have a list that looks like this: mylist = [ &sdesc &adesc &thedesc ] This construct is still legal, and is still interpreted with the "&" operators as unary operators, not bitwise AND operators. However, the parser now warns when such a definition is used; see the description of the new warning TADS-357 below for details. - The compiler will generate a new warning when it detects a unary operator within a list that could also be interpreted as a binary operator. For example, in this list, list2 = [ 5 -2 -6 -7 ] the "-" operators could be interpreted either as unary negation operators, which would result in a list with four elements (the numbers 5, -2, -6, and -7), or as binary subtraction operators, which would result in a list with only one element (the number -10). This same problem arises with the operators "+" and "&", since these also have a unary and binary interpretation which depends on context. In these cases, the compiler interprets the operators as unary operators, and issues a warning to let you know that the usage was ambiguous. The warning is TADS-357: TADS-357: warning: operator '-' intepreted as unary in list Note that this is a change from the previous version for the '+' and '-' operators. If your game depends on building lists from calculated numeric constants, you will need to change your code; we don't expect that any games actually depend on the old behavior. If you really do want the operators in these cases interpreted as binary operators, use parentheses: list2 = [ (5 -2 -6 -7) ] The parentheses tell the compiler that the expression is to be interpreted as a single list element. If you want the unary interpretation, and you want to suppress the warning, use commas between the list elements: list2 = [ 5, -2, -6, -7 ] This doesn't change the interpretation, but it does suppress the warning, because it removes the ambiguity: when the commas are present, there is no way the '-' operators could be interpreted as binary operators. You can suppress this warning using a new check box in the compiler's warning level dialog. Check the box to allow TADS-357 errors to be displayed. You may want to suppress this warning when compiling code written prior to this version of TADS, since the warning is generated in case you wanted the new meaning of the & operator. The check box enabling the warning is checked by default; uncheck it to suppress the warning. - A new compiler command-line option has been added: -C, a toggle option, which turns on and off C-language operator compilation. By default, C operator mode is off (-C-), which makes the compiler use the normal TADS operators. Specifying -C+ turns on C operator mode; specifying -C- disables C operator mode. When C-language operator mode is in effect, two operators are affected: the assignment operator becomes '=', and the equality comparison operator becomes '=='. With normal TADS operator mode in effect, assignment is ':=' and equality is '='. If you are a C programmer, and you're unhappy with the slight variation in operator notation between TADS and C, you can use -C+ to make TADS behave more like a real language. Thanks to the #pragma C options (see below), C operator mode has no effect on your choice of header files - you can use the same old adv.t and other header files unchanged, and still use C-style operators in your code. - A new preprocessor command has been added: #pragma. This special directive can be used to specify certain compiler options from within your source code. Currently, the only #pragma option available is the C operator mode option. Use #pragma C+ to turn on C operator mode, and #pragma C- to turn it off. The #pragma C+ and #pragma C- settings are local to a particular file. If a file is included by another file, the #pragma C settings specified in the included file will be in effect only until the end of the included file; the including file's #pragma C settings that were in effect before including the other file will be restored at the end of the included file. adv.t and std.t now start with a #pragma C- command - this allows adv.t and std.t to be included from a file with C-style operators (and thus a #pragma C+ or command-line C operator mode setting). Since the enclosing file's #pragma C option will be restored after the inclusion, files with different operator modes can be freely intermixed with #include, as long as each included file specifies its desired mode with a #pragma C directive. - The precedence of the comparison operators has been changed to be the same as that used by C. Previously, all of the comparison operators were at the same precedence; starting with this version, == and <> (and thus !=) are at the same level of precedence, and associate left to right as before, but <, >, <=, and >= are one level higher in precedence. The following type of expression will be affected: a > 1 <> b > 1 Previously, this grouped as: ( ( ( a > 1 ) <> b ) > 1 // obsolete This now groups as: ( a > 1 ) <> ( b > 1 ) // current behavior This shouldn't affect any existing code, since the old interpretation should always have resulted in an error (because a truth value, true or nil, can not be compared in magnitude to a number or other type). - Limited conditional compilation and preprocessor text substitution (#define) support has been added to the compiler. The following preprocessor directives are now available: #define symbol value #undef symbol #ifdef symbol #ifndef symbol #else #endif #define is used to assign a value to a preprocessor symbol. The "value" is simply text that will be substituted verbatim for the symbol whenever it occurs in your file (other than within quoted strings). For example: #define TEST say( 'hello from TEST!' ) myfunc: function { TEST; } The symbol TEST is replaced with its definition, so the function myfunc() displays "hello from TEST!" when called. Preprocessor symbols defined with #define are in a separate namespace from all other symbols in your program. Unlike a standard C preprocessor, no arguments are allowed in #define macros. #undef deletes a previously #define'd symbol. You can #undef the special symbols defined automatically by the compiler if you wish (see below). #ifdef tests to see if a preprocessor symbol is defined. If it is, the lines following the #ifdef line, and up to the corresponding #else or #endif, are included; otherwise, they are ignored. #ifndef is the opposite of #ifdef: #ifndef tests to see if the symbol is NOT defined. If the symbol is undefined, the lines following the #ifndef line up to the corresponding #else or #endif are included; otherwise, they are ignored. #else indicates that the lines between the #else and #endif are to be included if an only if the corresponding #ifdef (or #ifndef) failed. #else is optional. At most one #else is allowed per conditional. #endif terminates a conditional block. Exactly one #endif must appear for each conditional (#ifdef or #ifndef). You can use #ifdef to compile certain parts of your code conditionally. For example, if you want to include a verb only for your debugging version of a game, but you want to remove it from the final version, you could do something like this: #ifdef __DEBUG magicVerb: deepverb verb = 'xyzzy' action(actor) = { } ; #endif Note that __DEBUG is especially handy for this sort of thing, because the compiler automatically defines this symbol when debugging (-ds) is turned on (see below). - The compiler automatically defines several preprocessor symbols. These symbols can be used or tested within your code as needed. __TADS_VERSION_MAJOR is defined to a number indicating the major version number of the compiler (in the present system, 2). __TADS_VERSION_MINOR is defined to a number indicating the minor version number (in the present system, 2). __TADS_SYSTEM is defined to a string (single-quoted) identifying the operating system the compiler is running on. In addition, the same identifier contained in the string is defined as a preprocessor symbol itself (its value is always 1; it is intended that it will be tested with #ifdef, and not otherwise used). For example, if __TADS_SYSTEM is 'MSDOS', the symbol MSDOS will be defined to 1. If __TADS_SYSTEM is 'Macintosh', the symbol Macintosh will be defined to 1. __DEBUG is defined to 1 if debugging is turned on for this compilation (with the -ds compiler option). Otherwise, this symbol is not automatically defined. You can test the existence of __DEBUG with #ifdef to conditionally include code only when you are compiling for debugging. This might be useful if you want to include certain commands only in the debugging version of your game, and want to remove them when you actually deliver the game to players. If this set of symbols were entered manually with #define statements, the definitions might look like this: #define __TADS_VERSION_MAJOR 2 #define __TADS_VERSION_MINOR 2 #define __TADS_SYSTEM 'MSDOS' #define MSDOS __DATE__ is defined as a single-quoted string giving the system date when the compilation began, in the format "Jan 01 1980". __TIME__ is defined as a single-quoted string giving the system time when the compilation began, in a 24-hour format, "13:40:50". __FILE__ is defined as a single-quoted string giving the file being scanned at the point where the __FILE__ macro is encountered. Each time you use __FILE__, it will have the correct value for that point in your source code. __LINE__ is defined as a number giving the line number at the point where the __LINE__ macro is encountered. Each time you use __LINE__, it will have the correct value for that point in your source code. - The compiler has two new options that give you further control over preprocessor symbols. The -D option allows you to define a preprocessor symbol from the command line. For example, to define TEST to 5 from the command line, you could do this: tc -i/tads/include -DTEST=5 mygame.t Note that if you omit the equals sign, the default definition of the symbol will be 1: tc -i/tads/include -DTEST mygame.t This defines TEST to 1. The -U option undefines a predefined symbol. You can use this to undefine one of the symbols automatically defined by the compiler. You can also use it to undefine a symbol defined in a precompiled header, if you're loading one; -U is applied after the precompiled header is loaded, so it will undefine symbols loaded from the file. For example, to compile for debugging, but leave __DEBUG undefined, you could do this: tc -ds -U__DEBUG mygame.t The -U option is applied after all -D options, so you can also use it to undefine a symbol placed earlier on the command line. This may be useful if you are using a configuation file (CONFIG.TC) that contains -D options for symbols you sometimes want to undefine. - The compiler has a new preprocessor directive, #error, which allows you to generate your own error during compilation. If a #error directive is encountered, any text after the #error is displayed as a compiler error; an occurrence of #error is counted as an actual compilation error, so compilation will fail if #error is encountered. For example: #ifndef TEST # error TEST is not defined! #endif If the preprocessor symbol TEST is not defined at the point when this sequence is encountered, the compiler will display an error: mygame.t(181): error TADS-124: TEST is not defined! - The runtime has a new debugging feature that may help you track down problems with word definitions. You can make the player command parser generate a number of status messages as it analyzes a player's command; these messages provide information on how the parser is interpreting the words in the command. To activate this new debug mode, use the debugTrace function with these arguments: debugTrace( 1, true ); To turn the debug mode off, call with nil instead of true. This debugTrace function is always available, even when running under the normal runtime; the function returns no value when called with these arguments. - The built-in function incturn() has been extended to allow you to run a series of turns all at once. You can now specify a numeric argument to incturn(); the argument gives the number of turns that should pass. An argument of 1 causes incturn() to behave as usual. When an argument higher than 1 is given to incturn(), the function runs all of the fuses that are set to burn down within the number of turns specified, but not after that number of turns. Note that the normal incturn() has never actually executed any fuses, but simply burns down all fuses by one more turn. For example, if you call incturn(2), the system will first run any fuses that are set to burn down after 1 turn, then will shorten all remaining fuses by one more turn. - A new built-in function, skipturn(), has been added. This new function takes a numeric argument specifying the number of turns to skip; it must be at least 1. skipturn(n) is similar to incturn(n), except that it does not run any of the fuses that burn down during the 'n' turns - instead, it simply removes them without running them. - A new built-in function allows you to force capitalization off - this function, nocaps(), is the opposite of caps(). If you call caps() then call nocaps(), the next character is lower-case; if you call nocaps() then caps(), the next character is capitalized. Along with nocaps(), the special sequence \v has been added. Using this sequence in a displayed string is equivalent to calling nocaps(); this sequence is analogous to \^, which is equivalent to calling caps(). - The parser is now capable of disambiguating direct objects before indirect objects. By default, everything works as it always has - in a two-object command, the indirect object is disambiguated first, and then the direct object is disambiguated in the presence of the known indirect object. It is now possible, however, to specify that the reverse should be done. To do this, you use a new special flags syntax when defining your verb: tellVerb: deepverb verb = 'tell' desc = "tell" ioAction( aboutPrep ) = [ disambigDobjFirst ] 'TellAbout' ; The new special flags are placed in square brackets between the equals sign and the property template for the verb definition. The flags currently accepted are: disambigDobjFirst disambigIobjFirst Note that disambigIobjFirst is provided for completeness only; it is never needed, because it is the default setting. When the disambigDobjFirst flag is specified, it means that the command should have its direct object disambiguated before its indirect object. When the disambiguation order is reversed, the normal argument lists for verDoTellAbout and verIoTellAbout are interchanged. For our example, the prototypes for the verifier methods become: verDoTellAbout( actor ) verIoTellAbout( actor, dobj ) Normally, verIoVerb would not receive the direct object as an argument, because the direct object would not be known at the time of the verIoVerb call; and verDoVerb would receive the indirect object as an argument, because it would be known by the time the direct object was being tested. When the disambiguation order is reversed, however, so are the prototypes to these functions. The actual action method, ioTellAbout(actor, dobj), remains unchanged. All other methods also remain the same. When the direct object is disambiguated first, the player is not allowed to use multiple direct objects (or multiple indirect objects) in the command. If the player tries to do so, the new parseError message number 28 is displayed: >tell bob and bill about gun You can't use multiple objects with this command. - Note that a .GAM file format change was required to support the extra information needed for the disambigDobjFirst flag. The TADS file format is now format "C". The compiler is still capable of producing formats A or B, in case you need to generate .GAM files that can be played with versions prior to 2.2; however, if you use a format prior to C, you will not be allowed to use the disambigDobjFirst flag (or any other similar flags that may be added in the future). - Two new methods have been added to disambiguate actors. Previously, the system validated and disambiguated an actor by pretending that you were attempting to take the actor - takeVerb.validDo and the actor's verDoTake were used to validate and disambiguate the actor, when all you wanted to do was speak to him. This did not always produce satisfactory results, and in particular did not allow for such situations as talking over a radio to an actor in another room. To provide better control over actor validation and disambiguation, the system for testing actors has been enhanced. First, to validate an actor, the system now uses the method validActor in the actor object itself. This method takes no arguments; it returns true if the object is valid as an actor in a command, nil otherwise. This method is called before the verb or any of the objects involved in the sentence are known. Its function is not to determine whether the actor wants to receive the command, or even if the object can be used as an actor (actorAction is the place to do both of these tests), but rather simply to determine if the object can be addressed by the player at all. This method should return true if the actor is accessible by voice command (or whatever other means you want to provide for giving commands) to the player. The default thing.validActor in adv.t returns true if the object is reachable by Me, which provides roughly the same behavior as the old takeVerb-based mechanism. Second, to disambiguate an actor, the new preferredActor method has been added. This method is called if an actor is ambiguous. As with validActor, it doesn't take any arguments, and it returns true if the object is "preferred" as an actor, nil otherwise. If exactly one ambiguous object's preferredActor method returns true, the parser will use that object as the actor without further questioning the player; otherwise, the system will ask the player to disambiguate the noun as normal. In adv.t, movableActor defines preferredActor = true. An example of how these might be used: Sleeping Compartment You are in a sleeping compartment on a moving train. A pair of bunks is along each wall. There is a copper wire here. The train conductor is standing in the doorway, asking for your ticket. >look at conductor Which conductor do you mean, the copper wire, or the train conductor? >copper It's a piece of wire, about a foot long. >conductor, where is ivan? "Your ticket, please," is all the conductor has to say. In this sequence, when the command is addressed to "conductor", the parser matches both the copper wire and the train conductor. It checks validActor in each of them - both return true, since both are accessible to the player. (As described above, even though the copper wire couldn't possibly be an actor, it is valid as an actor at this point - it's not until its actorAction that we will decide that there's no point in talking to it.) So, the parser has an ambiguous actor. The parser tries to disambiguate the actor by testing preferredActor in each object. The copper wire's preferredActor returns nil; the train conductor's, however, returns true, because the conductor is a movableActor object. The parser now has only one object, and thus doesn't need to ask the player for further information. For compatibility with games compiled with previous versions of adv.t, the parser will continue to use the old mechanism (involving the takeVerb) if validActor is not defined in your game. Each time an actor is used, the parser checks to see if the first object in the list of possible actor objects has a validActor method defined; if not, the parser uses the old mechanism. If you use the new adv.t, all objects will at least inherit a validActor method (from thing), so testing for the presence of this method in any object lets the parser determine if the new mechanism can be used with the game. - A new parseError message has been added: number 27, whose default text is "You can't repeat that command." This message is displayed when the player types AGAIN, but the parser can't repeat the command; this is the case if one of the objects involved in the command is no longer accessible. - A new parseError message has been added, related to validActor (see above). This new message, number 31, is used when none of the objects matching the vocabulary for an actor in a player's command can be used as an actor. The default text of this message is "You can't talk to that." For example, if there is no object matching the vocabulary "guard" whose validActor method returns true, but an object named "guard" is visible to the player, the message is used: Security Room You are inside a small cubicle. A thick, laser-proof (as you now know from your ill-fated attempt) glass door (closed) is to the north. Through the door you can see a guard standing watch. >guard, open door You can't talk to that. This message is used for actors in place of the standard cantReach processing done for direct and indirect objects under these conditions. - A new parseError code, number 29, has been added. The default message is "I think you left something out after 'any of'", and is used when the player uses "any of" in a sentence, but doesn't follow it with anything. - Using the same word as both a plural and a noun works much better now. The parser will first attempt to use such a word as a plural; if no objects match the plural usage, the parser will try to use the word as a noun instead. - "of" can now be used as a preposition. In previous versions of the run-time, "of" was exclusively a special word that was embedded in noun phrases (such as "pile of paper"). The runtime will still allow "of" to be used in noun phrases as before, but it also will treat "of" as an ordinary word when, based on the context, it does not appear to be part of a noun phrase. The parser will still attempt to treat "of" as part of a noun phrase whenever it matches an object. For example, if you have an object with nouns matching "pile of paper", then the following interpretations will apply: accuse bob of murder -> dobj = bob, iobj = murder, prep = of accuse pile of paper -> dobj = pile of paper Note that ofPrep, defining "of" as a preposition, has been added to adv.t. - All of the system verbs that use "abort" have been modified slightly in adv.t to make it easier to augment their behavior with the 'modify' statement. All of the processing other than the "abort" has been moved out of the doVerb (or action) method in each case, and put into a new method. For example, saveVerb's action routine now looks like this: action( actor ) = { self.saveGame( actor ); abort; } The new method saveVerb.saveGame(actor) now performs all of the processing that the action(actor) method previously performed. The benefit of this change is that you can now modify the saveGame(actor) method, and inherit the original behavior, without having to worry about an "abort" interfering with the order of operations. For example: modify restoreVerb restoreGame( actor ) = { // restore the game as usual - check for success if ( inherited.restoreGame( actor ) ) { // re-randomize the puzzle "The carnival hawker flashes a mischievous smile at you. \"There's no use trying to guess the answer,\" he says. \"I changed around the shells while you were busy restoring!\" "; puzzle.answer := rand( 100 ); } } ; - The format mask fmtMe has been added. You can now use %me% in messages to refer to the actor. For basicMe, fmtMe is set to the message "me"; for other actors, it is set to the actor's thedesc. In adv.t, thing.ldesc has been changed to use %me%: "It looks like an ordinary <<sdesc>> to %me%." This makes the default sentence somewhat more adaptable if you ask another actor to describe something: >guard, look at the card It looks like an ordinary card to the guard. - AGAIN, WAIT, and SLEEP are now darkVerb's in adv.t. - A new verb, breakVerb, has been added to adv.t. The vocabulary words for this verb are 'break', 'destroy', and 'ruin', and it provides a single-object command "break <direct-object>". The thing class has been adjusted so that verDoBreak(actor) validates breaking any object, but doBreak(actor) simply displays "You'll have to tell me how to do that." If you want to make a breakable object, simply override doBreak(actor) so that it breaks the object (you may also want to override verDoBreak(actor) so that it doesn't allow a broken object to be broken again). - "there" has been added a synonym for "it" in the specialWords list in adv.t. This allows sentences like this: >get box. put ball in there. - lightsource now has a doTurnnon method in adv.t. This method will show the room's description if the room becomes lit as a result of turning on the lightsource. Note that lightsource, by default, has no verDoTurnon, so you can't turn a generic light source on and off. However, if you add switchItem to the superclass list of a lightsource object, you will have a light source that you can turn on and off, and which will have this new behavior. Note that you should put lightsource in the superclass list prior to switchItem, so that lightsource.doTurnon overrides switchItem.doTurnon: flashlight: lightsource, switchItem sdesc = "flashlight" noun = 'flashlight' 'light' adjective = 'flash' location = tunnel ; - verIoGiveTo and ioGiveTo have been added to movableActor in adv.t. verIoGiveTo rejects the command if the actor is the same as the indirect object, otherwise the command is accepted. ioGiveTo always rejects the offer. In addition, ioGiveTo has been added to basicMe; the method always accepts anything from another actor, because this method will only be called in response to commands such as: >guard, give me the key - A small problem with thing.isVisible in adv.t has been fixed. If the vantage is inside the object, and the object's contents are visible, isVisible returns true. This is is needed in certain situations involving nested rooms. - moveableActor.travelTo(room) in adv.t has been corrected so that it does nothing when room = nil, which is the case when the actor can't travel in the desired direction. Previously, the "noexit" message would be displayed, but then the actor would be moved into a nil location. - moveableActor now has a roomCheck method in adv.t. The method is the same as basicMe's roomCheck method; its omission in previous versions was an oversight. - The showcontcont function in adv.t has been corrected so that the isqsurface flag is checked correctly. - A new class, seethruItem, has been added to adv.t. This class is intended for objects such as windows or magnifying glasses which the player can look through. Each object of this class should define an appropriate thrudesc method, which displays what the player sees when looking through this object. Note that a seethruItem is not the same as a transparentItem. The class transparentItem is intended for objects, such as glass bottles, whose contents are visible, whereas seethruItem is intended for objects that are not containers but which the player can look through. - The compiler now sets an error code on exit. If you are using a MAKE utility or other program-building tool, you can use the exit code. On success, the compiler uses exit code 0; if any errors occurred, a non-zero exit code is used. - The compiler no longer creates a .GAM file if errors occurred during compilation. If a .GAM file of the same name exists prior to a compilation, and errors occur, the original .GAM file is unaffected (it is not deleted or overwritten). Although the compiler previously produced a .GAM file even when an error occurred, this .GAM file was not generally usable; to avoid confusion, the compiler no longer produces a .GAM file at all when an error occurs. - The compiler performs more checking for invalid memory options. When memory options are entered that exceed the compiler's internal limits, the compiler will report an error (after the Compile button is pushed) and halt the compilation. The affected settings are the parse pool size, local symbol table size, and the stack size. The runtime similarly checks its parameters more carefully now. - $$ABEND can now be used after a question from the parser, such as during disambiguation and when OOPS is permitted. - The runtime no longer displays anything on the status line at startup. It initializes both the left portion (which normally is used to display the location) and the right portion (which is normally used to display the score and turn count) to empty strings. To ensure that a score is properly displayed at the start of the first turn, we added a call to scoreStatus(0, 0) in the "init" function defined in std.t. - The runtime handles hyphenation better. Multiple hyphens will no longer be split across lines - so if you use two hyphens together for a dash, both hyphens will always be grouped on one line. Furthermore, the runtime formatter will never put a dash at the very start of a line; if a line must be split at a dash, the formatter will put the dash at the end of the line, then break the line, and will back up and split at the previous word if necessary. - The runtime will now properly convert "\" sequences in askfile() prompts properly. If you use a \n, \t, \', \", or \\ sequence in a prompt to askfile(), the sequence will be displayed as the appropriate character. - The Mac runtime's startup dialog has an additional option that lets a user show all files, rather than just files that the runtime recognizes as TADS game files. This should make it easier to run a game transferred from another system - since you can now run a game regardless of its type/creator settings, you can simply transfer a file from another operating system and run it directly. To show all files, click the radio button labelled "Show All Files" at the bottom of the file dialog; to return to showing only TADS game files, click the radio button labelled "Show TADS Games Only." - The TADS Executable Game Builder now lets you specify run-time command options that should be used when the game is executed. This new feature, which is optional, lets you specify a set of run-time options that you want to be in effect every time your game is run. To specify command options for your game executable, you must first create a file. Use the same format as CONFIG.TR - simply enter your options into the file as you would on a TR command line; separate options by newlines or spaces. For example, to specify a minimal cache size and a swap file of SWAP.DAT, you could make your CONFIG.TR file look like this: -m0 -tf swap.dat See the Author's Manual chapter on the run-time command-line options. Even though the Macintosh version of the run-time doesn't normally use a command line at all, you must still enter options into a file using the command line option format if you want to combine them with your game. Once you've created a file with your command options, specify that file to the Executable Game Builder by selecting it with the new file selector dialog that appears after you specify the game file. If you don't want to combine an options file with your game, simply cancel this dialog. Once the config file is bound into your executable, its options will be used every time a player runs the game. Note that you may want to avoid specifying anything specific to your system, such as volume or folder names, since that may prevent the game from working properly on someone else's computer. - The Macintosh compiler's "memory options" dialog box has been corrected so that it accepts settings over 32767. Memory settings up to 65535 can now be entered. - The Macintosh compiler no longer displays "Compilation Completed" when compilation fails or is interrupted. Instead, it displays the new message "Compilation Terminated", to make it clear that the compilation did not complete normally, whenever errors occur during a compile, or the compilation is cancelled by Command-Period. - The Macintosh compiler has been corrected so that it doesn't add ".t" to the end of source file names any more. In previous versions, the compiler always added ".t" to the end of a filename if the filename didn't contain at least one period; while this behavior is desirable on other computers (since it allows command-line users to omit the default filename extension, saving typing), it's unnecessary and incorrect on the Macintosh. - The Macintosh run-time's formatting system has been improved so that it will no longer insert spaces after hyphens. Previous versions occasionally inserted a space after a hyphen, even when the original text had no spaces after the hyphen. - The new sentence parsing for the form VERB PREP IOBJ DOBJ (introduced in 2.1.1) causes a subtle problem: if you create an object with an adjective that is also a preposition, the system attempts to interpret sentences with a single-word verb that refers to the object as VERB PREP IOBJ. The result is this: >push off button What do you want to push? This is because the parser is interpreting the sentence as "push something off button", and needs to know the "something". This problem has been corrected. Now, the parser will check this type of case to see if the preposition can also be used as an adjective, and if so, checks to see if a noun (possibly preceded by one or more adjectives) follows; if this test is met, the word will be interpreted as an adjective, as it should be. - The parser now correctly distinguishes between cases involving a word that is defined as both a preposition and an adjective. The parser previously did not accept sentences such as this: >enter south wall when 'south' was defined as an adjective. Because 'south' was also defined as a preposition (in adv.t), the parser attempted to interpret this sentence as though 'enter south' were a verb (in the same manner as 'pick up' or 'put down'). The parser now checks to make sure that 'enter south' is a valid combination verb; if it's not, and 'south' is also defined as another part of speech, the parser assumes that 'enter' is the verb, and treats 'south' as an adjective. - The parser previously asked to disambiguate a direct object twice if askio( prep ) was used. For example: >unlock door Which door do you mean, the large door, or the small door? >large What do you want to unlock it with? >key Which key do you mean, the silver key, or the gold key? >gold Which door do you mean, the large door, or the small door? >large The door unlocks with a satisfying click. This has been corrected - the parser now only asks once about the door. - The parser did not previously accept a word during disambiguation if the word was defined as both a noun and an adjective. For example, if you've defined objects "violet paper", "violet banana", and "paper towel", and the parser asked you this: >x violet Which violet do you mean, the violet paper, or the violet banana? then you couldn't respond with "paper". This has been corrected. - The inputkey() function now clears the "more" line counter. So, when inputkey() is called, a "more" prompt will not show up until another screenful of text has been displayed. - "local" statements that occur out of context (i.e., as other than the first statements after an open brace) now generate better diagnostics. - Dividing by zero is now flagged as a run-time error. - A problem involving the embedded string << >> notation has been corrected. Under certain circumstances, if one expression used in an embedded string invoked another string with an embedded expression, an error occurred (usually "invalid type for built-in function"). This should no longer occur. - The system did not properly handle lists containing function pointers. This has been corrected. - A problem involving pre-compiled headers and 'modify' has been corrected. Several people have encountered problems that generally were manifested as "assert" failures in mcm.c (the cache manager) when using 'modify' and pre-compiled headers; these should no longer occur. - An internal cache corruption occurred under certain obscure circumstances involving 'modify'. This has been corrected. - A note on roomCheck: if you return nil from roomCheck, fuses and daemons are NOT run; in this sense, returning nil from roomCheck is equivalent to using abort in other methods. (This is not a change - it's always worked this way - but this behavior is not mentioned in the TADS Author's Manual.) - A note on using << >> embedded strings: If you put a newline immediately before the << of an embedded string, any spaces between the last non-space character preceding the << and the << will be lost. If you want a space before the <<, do not put it on a new line. Instead, you can put it at the end of the line, and put the embedded expression itself on the next line. For example: embeddedString = "embedded string" sdesc = "This is a message with an <<self.embeddedString>>! " // wrong This will display as follows: This is a message with anembedded string! If you intend a space to precede the embedded string, you should write this as follows: sdesc = "This is a message with an << self.embeddedString>>! "; // right (This is not a change, but simply a note for game developers who have encountered this problem.) 2.1.2 11/22/93 enhancements, bug fixes - You can now detect when the player uses multiple direct objects with a verb, and reject such commands. Whenever the player uses multiple direct objects with a command (or uses "all", even if it results in a single object being used), the parser calls the verb object's rejectMultiDobj(prep) method. If you don't wish to take any special action for multiple direct objects used with a particular verb, simply return nil from this method (or don't define the method at all for the verb). If you want to prevent multiple direct objects from being used, however, you should display an appropriate message, and return true. The parser will skip the command entirely. Note that the parser doesn't display any additional message when rejectMultiDobj(prep) returns true; the method should display whatever message is desired. The "prep" parameter is the preposition object used with the command; it will be nil if no indirect object is present. An example: modify inspectVerb rejectMultiDobj( prep ) = { "You can only look at one thing at a time."; return true; } The verb's rejectMultiDobj(prep) method is called immediately before the actor's actorAction method. Note that the parser will continue processing any remaining commands on the line, and will then run daemons and fuses as normal, even if rejectMultiDobj(prep) returns true; if you want to stop the current turn altogether, use abort. - The player command parser now gives you greater control over object validation error reporting. In previous versions, if an object was visible but did not pass the validIo/validDo test, the parser called the object's cantReach method to report the error (see the note below about an additional change to object.cantReach processing). Now, however, the parser will call verb.cantReach instead, if the command's deepverb object defines (or inherits) a cantReach method. If the verb does not have a cantReach method at all, the parser will use the old behavior instead. The new cantReach method should be defined as follows: myVerb: deepverb verb = 'whatever' cantReach( actor, dolist, iolist, prep ) = { // your code here } ; This method doesn't return a value; it simply displays the appropriate message explaining why the object can't be used with the command. verb.cantReach is used only when the objects are visible (that is, object.isVisible(actor) returned true for each object in the list). Only one of dolist or iolist will be non-nil. If the direct object of the command refers to one or more objects that are visible but can't be used (according to validDo), dolist will be a list of all such objects, and iolist will be nil. Otherwise, iolist will be a list of such objects used for the indirect object, and dolist will be nil. adv.t has not been changed to use verb.cantReach. This change has been made to provide finer control for game authors implementing their own verbs and object validation procedures. - The player command parser had an odd quirk when ambiguous nouns were used with transparent items. If the player used a command containing a noun that referred to multiple objects that were visible but were not valid for the verb (for example: "take trophy" in a room containing a closed glass trophy case containing a bowling trophy and a tennis trophy), the parser asked the normal disambiguation question. This was not really necessary, because the parser already knew that the objects were invalid. This has been changed; the parser now simply uses the cantReach message for *each* object that is visible and matches the vocabulary, using the usual multiple-word format:
bowling trophy: You'll have to open the glass case first.
tennis trophy: You'll have to open the glass case first.
This new behavior should have no effect on your game code. Note
that it is entirely irrelevant if you use the new verb.cantReach
feature described above.
- The compiler sports a new case sensitivity option. By default,
the compiler is case-sensitive, as it has been in past versions.
However, the new toggle option allows you to change this. Specify
-case- to turn off case sensitivity (the default is -case+). Note
that this is a toggle option, so simply using -case will reverse
the current case sensitivity (which is useful if you use a CONFIG.TC
file that sets a non-default case option). When case sensitivity
is turned off, the compiler will treat upper- and lower-case letters
in symbols (names of objects, properties, functions, and local
variables) as equivalent. Hence, foodItem = fooditem = FoodItem,
and so on.
If you create a pre-compiled header with -w, any compilation which
reads that binary header with -l will use the same case sensitivity
as was in effect when the header was pre-compiled. The -case option
is ignored when a pre-compiled header is loaded. Likewise, the
debugger uses the same case sensitivity that was in effect when the
game being debugged was compiled.
- The debugger's command set is no longer case-sensitive (hence,
BP = Bp = bP = bp).
- adv.t has a new darkVerb class. This is a type of deepVerb that
can be used in the dark. The darkroom class has been changed to
accept any verb of class darkVerb in its roomAction and roomCheck
methods. The travel verbs and system verbs have all been made
darkVerb objects, so darkroom only needs to check the single
verb type.
In a related change, turnOnVerb and dropVerb have been changed to
be darkVerb objects, allowing the player to turn on an object or
drop it in the dark. The verDoTurnon method in switchItem has
been changed so that it checks to see if the player is in a dark
room; if so, the item can only be turned on if the player is already
carrying the object. This allows the player to turn on a light
source that's already being carried, but doesn't allow the player
to pick up a light source in a dark room.
- The compiler issues a new warning message (TADS-452) if you
use the same verb with two deepverb objects. The parser can only
choose a single deepverb object for any verb typed by the player,
so you should never define the same 'verb' vocabulary word in more
than one deepverb object. In past versions, the compiler did not
flag this as a warning.
- Several improvements have been made for numbers in player
commands. First, multiple numbers are now allowed in a single
commands; for example, the player can now say "press 1, 2, 3,
4 on keypad," and the numbers are set in numObj.value, one by
one. Second, the sdesc, adesc, and thedesc properties of
basicNumObj have been improved to show the number's value.
- Similar improvements to those for numbers have been made for
strings. Multiple strings are now allowed in a single command,
and the basicStrObj properties sdesc, adesc, and thedesc have
been improved to show the string's value.
- specialWords has been enhanced. First, in past versions, if a
game contained multiple specialWords statements, the word lists
were additive - all specialWords lists were used in the game.
This has been changed so that each specialWords statement replaces
any previous list in effect. However, you now can explicitly add
to the specialWords list, without removing any of the previously
defined words, by using "modify specialWords". When you use
'modify', you can use nil in any word slot if you do not wish
to add any words for that slot. Finally, you can use "replace
specialWords" to make the replacement explicit; this is the default
if neither 'modify' nor 'replace' is specified, but the compiler
will now issue a warning (which is harmless) if you use specialWords
without 'replace' or 'modify' and a previous specialWords list is
already in effect.
- The words "one" and "ones" (or their equivalent for your game,
if you've changed them with specialWords) are no longer considered
reserved words within normal commands. This allows you to use
objects such as a "one dollar bill"; previous versions rejected
player commands containing "one" or "ones". These words are now
considered special only during the parsing of a response to a
disambiguation question, when they can be used in place of a
noun ("the red one" can be used in answer to "Which book do you
mean...").
- The hider class has been changed so that 'it' or 'them' (as
appropriate) are set to the object or objects found when
searching the hider.
- The verDoPutIn and verDoPutOn messages in thing and surface
(respectively) have been improved for the somewhat obscure case
of attempted circular containment - that is, putting an object
into a container, when the container is already in the first object
(either directly or by virtue of being inside another object which
is inside the first object, or inside an object which is inside an
object which is inside the first object, and so on). The new
method thing.circularMessage(iobj) is called in these cases to
display an appropriate message; the default implementation of this
method displays the complete list of containers of the direct
object out to the indirect object. For example, if you have a
crate which contains a box, and you try to "put crate in box",
the message is "You can't put the crate in the box, because
the box is already in the crate."
- The default doTake method has been changed to include the weight
of any contents of the item being taken, in addition to the item
itself, to determine if the actor's inventory is too heavy.
The old doTake method only included the weight of the object
being taken, not counting its contents.
- The Actor class has been changed to add a travelTo method. You
can now move any actor (Me included) with travelTo(destination).
The default Actor.travelTo method moves the actor; it announces
the departure of the actor if the actor was in the same location as
Me before leaving (and the location is lit); and it announces the
arrival of the actor if the actor is moving into the same location
as the player (and the location is lit). The departure message
is generated with a call to self.sayLeaving, and the arrival
message is generated with self.sayArriving. The default versions
of these methods simply display "Thedesc leaves the area" and
"Thedesc enters the area", respectively; you can override these
methods if a more specific message is desired.
- When modifying a class object with 'modify', the modified object
was not a class unless the 'class' keyword was included with the
'modify' statement ("modify class foo" rather than "modify foo").
This has been corrected; a modified class is still a class.
- outhide(true) now returns a status indicator, which is a value that
can be used in a subsequent call to outhide() to return output
hiding to the state it was in before the outhide(true). This
allows you to nest text hiding. When you use the nested form
(which you do simply by using the return value of outhide(true) as
the parameter - in place of nil - to the subsequent call to outhide()),
the value returned by the second outhide() indicates whether any
text output occurred ONLY BETWEEN THE NESTED CALLS. For example:
old_stat1 := outhide( true );
"This is some hidden text. ";
old_stat2 := outhide( true );
// write no text here
new_stat2 := outhide( old_stat2 );
new_stat1 := outhide( old_stat1 );
Because outhide(old_stat2) indicates whether any output occurred
during the NESTED outhide(true), new_stat2 = nil. However, new_stat1
= true, since output occurred after the first outhide(true). Consider
another sequence:
old_stat1 := outhide( true );
// write no text here
old_stat2 := outhide( true );
"This is some hidden text.";
new_stat2 := outhide( old_stat2 );
new_stat1 := outhide( old_stat1 );
In this case, both new_stat1 and new_stat2 will be true, because
hidden output occurred within both nested sections.
The general form of a nested hidden output section looks like this:
{
local original_hide_stat;
local nested_stat;
original_hide_stat := outhide( true );
// do whatever you want to do while output is hidden
nested_stat := outhide( original_hide_stat );
}
Now nested_stat will indicate whether any output occurred during
the nested outhide() - that is, between the outhide(true) and
the outhide(original_hide_stat). In addition, output hiding will
be returned to the same state it was in prior to the original
outhide(true).
- The random number generator has been improved. Many people have
complained about the many undesirable properties of the old
generator, especially when small upper limits were used. The
interface to the new random number generator is the same as
before - call rand(upper_limit), which will return a uniformly
distributed random number from 1 to upper_limit, inclusive.
Note that the old random number generator will still be used if
you don't call randomize(). This allows test scripts (which require
a fixed sequence of random numbers in order to be repeatable) that
were written with older versions to continue to operate unchanged.
If you want numbers from the improved generator, be sure to call
randomize().
- When 'modify' was used on an object, the compiler sometimes did
not correctly apply the original object's vocabulary and location
to the new object. This has been corrected.
- restore() and undo() have been changed so that they always cancel
all pending commands on the command line. In the past, if the
player typed several commands, and something happened (such as
the player character dying) during one of the commands that led to
an undo() or restore(), the remaining commands were still
executed. This has been fixed.
- If you explicitly set an object's location to nil in its object
definition, and the object inherited a location from a superclass,
the system incorrectly placed the object in the contents list of
the object named in the location inherited from the object's
superclass. This has been corrected.
- "abort" can now be used within a daemon or fuse, and the
expected behavior will occur. In the past, "abort" within
a fuse (or daemon) merely exited from the current fuse,
but the remaining fuses and daemons were still executed.
Now, "abort" will cause the entire turn to end; no more
fuses or daemons will be executed on the current turn.
2.1.1.1 10/07/93 minor bug fix
- The Mac version has for a long time displayed parentheses when
the \( and \) sequences (for begin/end highlighting) were used.
This has been corrected. (But the Mac version still doesn't
actually do anything for highlighting yet - sorry.)
2.1.1 09/09/93 enhancements, bug fixes
- You can now access objwords( 1 ) while deciding whether to use a
default direct object in doDefault. This is useful mostly if
you want to prevent players from being able to use "all" with
certain verbs, but still want to generate a default direct object
for the verbs. To do this, you can detect when objwords( 1 ) = [ 'A' ]
('A' is the parser's internal code for "all", which saves you the
trouble of checking for "everything" and shorter abbreviations as
well as "all"):
doDefault( actor, prep, iobj ) =
{
if ( objwords( 1 ) = [ 'A' ] )
{
global.allMessage := 'You can\'t use "all" with this verb. ';
return [];
}
/* your normal default object code goes here */
}
If you wish, you can also suppress the default message that the
parser will generate ("I don't see what you're referring to").
To do this, you'll have to write your own parseError() function
and detect when an "all" violation has occurred (cleverly using the
global.allMessage, which we set above for this purpose):
parseError: function( str, num )
{
// if there's an allMessage waiting, use it instead of the default
if ( global.allMessage <> nil )
{
local r;
r := global.allMessage;
global.allMessage := nil;
return r;
}
else
return nil;
}
- The Macintosh version of the run-time (and debugger) did not work
correctly with long text displays in the "score" section of the status
line. Using a long score display resulted in lost text in the main
text window. This has been corrected.
- The compiler's error message format has been changed slightly
to work better with editors and workbench programs that scan error
logs to go to lines with errors. The format is now:
file(line): error TADS-xxxx: message
For example:
deep.t(1151): error TADS-300: expected colon
- The parser now accepts sentences of the form VERB PREP IOBJ DOBJ,
where the PREP is *not* part of the verb. For example, GIVE TO THE
MAN THE BALL. This change has two benefits. First, while this
type of sentence is not common in English, some other languages
allow this type of phrasing, so the parser is now somewhat more
adaptable to non-English languages. Second, this allows for
object defaulting and command completion when specifying just the
indirect object, which was not possible before. For example, if
the player types ASK FOR A BEER, the parser will be able to attempt
to provide a default (if one is available), or at least ask for the
direct object. Previous versions would simply say "I don't understand
that sentence." Note that the parser still attempts to combine the
verb and preposition into a single phrase; the new action happens
only when the verb and preposition don't go together (that is, they
haven't been defined together as a "verb =" property of a deepverb).
For example, suppose that a line like this appears in a deepverb:
verb = 'pick up'
In this case, PICK UP THE BOX will use THE BOX as the direct object,
just as in previous versions. Only when the verb-preposition combination
is not specifically defined in a verb will the new phrasing be used.
- When no preposition is specified between the direct and indirect objects,
the parser will now evaluate a new property, nilPrep, in the deepverb
object. This property should return the preposition object that should
be used as the preposition between the objects. Previous versions of
TADS always looked for an object that defined the word 'to' as a
"preposition =" property. While 'to' is almost always the correctly
the correct preposition to substitute in English, it's obviously the
wrong word in other languages; furthermore, the correct word in other
languages is sometimes a function of verb. If no nilPrep property is
defined for the deepverb, the parser will still use the object whose
"preposition =" property matches the word 'to'.
- The class transparentItem in adv.t has been modified so it works better
when you define an object that inherits from both transparentItem and
container or openable. First, an ldesc has been added so that the
contents of a transparentItem are listed by default with the ldesc.
Second, the "look in" command now works on a transparentItem. In
addition, the openable class has been changed so that the "look in"
command can be used when an openable is also a transparentItem, even
when the openable is closed (because you should be able to see the
contents of a transparentItem regardless of whether it's open or closed).
Thanks to Ron Hale-Evans for pointing out this problem and finding the
solution.
2.1.0 04/07/93 new features, enhancements, bug fixes
- TADS finally has a way of changing objects and functions in
adv.t without changing adv.t itself. The new mechanism allows
you to entirely replace a previously defined object or function
with one of your own, and also lets you modify a previously
defined object by adding or overriding properties. Two new
keywords have been added to the language to support these new
features: "replace" and "modify".
Using these new features, it should be possible to make most
of the changes to adv.t that are necessary while writing a game
without actually changing the file adv.t itself. This should
make version upgrades much easier to apply, since you shouldn't
need to reconcile any changes you have made to adv.t with the
new version.
High Energy Software requests that you advise us of any changes
to adv.t that would facilitate modification and replacement of
the objects defined in adv.t. Examples would include common
code fragments that could be moved into a function for easy
replacement, and single deepverb objects that should be split
into multiple objects.
You can replace a previously-defined function with a new
definition simply by prefacing your new definition with the
keyword "replace"; for example, to replace adv.t's new
scoreStatus function, you could do this:
#include <adv.t>
replace scoreStatus: function( points, turns )
{
setscore(cvtstr(pts) + ' points/' + cvtstr(turns) + ' moves' );
}
You can do the same thing with objects. For example, to replace
a verb in adv.t, you could do something like this:
#include <adv.t>
/* we don't want "buckle", so replace adv.t's fastenVerb */
replace fastenVerb: deepverb
verb = 'fasten'
sdesc = "fasten"
prepDefault = toPrep
ioAction( toPrep ) = 'FastenTo'
;
Replacing an object entirely deletes the previous definition of
the object, including all inheritance information and vocabulary.
The only properties of a replaced object are those defined in the
replacement; the original definition is entirely discarded.
You can also modify an object, which retains its original definition
(including inheritance information, vocabulary, and properties), and
allows you to add new properties and vocabulary. You can also
override properties, simply by redefining them in the new definition.
The most common addition to an object from adv.t will probably be
new verb associations; for example:
modify pushVerb
verb = 'nudge'
ioAction( withPrep ) = 'PushWith'
;
Note several things about this example. First, no superclass
information can be specified in a "modify" statement; this is because
the superclass list for the modified object is the same as for the
original object. Second, note that vocabulary has been added.
The additional vocabulary does NOT replace the original vocabulary,
but simply adds to the previously-defined vocabulary. Further note
that verb association pseudo-properties, such as doAction and ioAction,
are legal in a "modify" definition.
In a method that you redefine with "modify", you can use "pass"
or "inherited" to refer to the REPLACED method. In essence, using
"modify" renames the original object, and then creates a new
object under the original name; the new object is created as a
subclass of the original (now unnamed) object. There is no way
to refer to the original object, except indirectly through the
new replacement object. Here's an example of "modify" and "pass":
class testClass: object
sdesc = "testClass"
;
testObj: testClass
sdesc =
{
"testObj...";
pass sdesc;
}
;
modify testObj
sdesc =
{
"modified testObj...";
pass sdesc;
}
;
Evaluating testObj.sdesc results in this display:
modified testObj...testObj...testClass
However, you can override this behavior for a property by
using the replace keyword on the property. In the example
above, we could do this instead:
modify testObj
replace sdesc =
{
"modified testObj...";
pass sdesc;
}
;
This would result in the following display for testObj.sdesc:
modified testObj...testClass
The "replace" keyword before the property definition tells the
compiler to completely delete the previous definitions of the
property. This allows you to completely replace the property,
and not merely override it, meaning that "pass" and "inherited"
will refer to the property actually inherited from the superclass,
and not the original definition of the property.
- The dobjGen and iobjGen mechanism has been changed slightly.
In the original implementation, you could prevent the system
from calling dobjGen/iobjGen by defining an appropriate verXoVerb
property in the actual object, but NOT in a superclass. This
made it impossible to define a class that had exceptions to
dobjGen/iobjGen except by explicitly testing for those verbs
in the xobjGen routines.
The change is that the system will now skip calling xobjGen
if an appropriate verXoVerb/xoVerb property is defined in such
a way that it "overrides" xobjGen for the object. Here's an
example:
class cursedItem: item
dobjGen( a, v, i, p ) =
{
"As you touch <<self.thedesc>>, a bolt of lightning
leaps from the object and sends you reeling away!";
}
iobjGen( a, v, d, p ) = { self.dobjGen( a, v, d, p ); }
verDoInspect( actor ) = { pass verDoInspect; } // allow 'inspect'
;
The change means that the presence of verDoInspect in the *class*
prevents the system from calling dobjGen when the verb is "inspect",
even for subclasses. With the old system, since the subclass objects
themselves didn't define verDoInspect, dobjGen would be called even
though the verDoInspect logically overrides the dobjGen.
- The restore() intrinsic has been extended to allow your game
program to explicitly restore the saved game specified by the
user as a parameter to your stand-alone game program. This is
currently only useful on the Macintosh, but the inclusion of
code to test for this case will make your game work better on
the Macintosh (and possibly other platforms in the future).
The new functionality is invoked by calling restore(nil). If
a saved game was specified by the user at start-up time, the
game will be restored, and nil will be returned. If no file
was specified, or an error occurred restoring the game, the
function returns true. To use this new behavior, we recommend
placing the following code in your init function, before your
introductory messages and other startup code:
// check for a file to restore specified as a startup parameter
if (restore(nil) = nil)
{
"\b[Restoring saved game]\b";
scoreStatus( global.score, global.turnsofar );
Me.location.lookAround( true );
return;
}
Note that the run-time will still automatically restore the
game provided as a parameter (on the Macintosh) after init returns
if you do NOT include this code in init. The reason for including
this code is that it provides your game with greater control over
the sequence of events during startup. If you allow the run-time
to perform the restore automatically, your entire init function will
be executed; this may be undesirable, because it forces the user to
view the entire introductory text even though they'll immediately
restore a game after reading it. If you place the restore(nil) call
before your introductory text, the user will be spared the long text
display; however, you'll still have complete control over any text
that you want the user to see even when restoring a game, such as
your copyright message.
- New built-in function: inputkey() reads a single keystroke from
the keyboard. The function takes no arguments. When called,
inputkey() will flush any pending output text, then pause the game
until the player hits a key. It then returns a string containing
the single key hit by the player. Note that the function does NOT
provide a portable mechanism for reading non-standardized keys;
special keys such as cursor arrow keys and function keys will return
a string specific to the type of computer being used. Your game
will not be portable if you make use of any non-standardized key
values returned by inputkey(). To ensure portability, use inputkey()
strictly with standard ASCII keys (alphabetic, numeric, and punctuation
keys). It is also fully portable if you simply ignore the return value
and use the function only to pause and wait for a key.
- Several new parser-called user functions have been added that allow
better user control over the generation of parser messages. The
new functions have been added because some people have found
that the parseError() function is not sufficiently flexible
for some situations, because it only allows changing the text
of messages on a piecewise basis; when complete messages need
to be built out of several pieces, it's necessary to be able to
take over the entire process of building the message. The new
functions allow full control of the generation of certain messages.
parseAskobj(v, ...): This function is called when the parser
needs to ask the player for a direct or indirect object to complete
the command. For example, if the player just types "take", and
several objects are present that could be taken, the parser must
ask the player what to take. If a direct object is being requested,
the function will have only one argument (the verb). If an indirect
object is being requested, the function will have *two* arguments;
the second argument will be the preposition. Note that the preposition
can be nil, in which case you can assume that "to" is to be used.
The implementation below emulates the default behavior.
parseAskobj: function( v, ... )
{
"What do you want to <<v.sdesc>>";
if ( argcount = 2 )
{
local p := getarg(2);
" it << p ? p.sdesc : "to" >>";
}
"? ";
}
parseDisambig(string, list): This function is called by the
parser when objects need to be disambiguated. If this optional
function is provided, it is called with the string that the player
typed which is in need of disambiguation, and a list of the objects
that match the string. The implementation below emulates the
parser's default behavior.
parseDisambig: function( str, lst )
{
local i, tot, cnt;
"Which << str >> do you mean, ";
for ( i := 1, cnt := length( lst ) ; i <= cnt ; ++i )
{
lst[ i ].thedesc;
if ( i < cnt ) ", ";
if ( i + 1 = cnt ) "or ";
}
"? ";
}
parseError2(v, d, p, i): The parser calls this function to
generate the default error message stating that the verb attempted
isn't accepted by the objects involved; this happens when either
the indirect object doesn't define an appropriate verIoXxxx method,
or the direct object doesn't define an appropriate verDoXxxx method.
Only one of 'd' (direct object) or 'i' (indirect object) will be
non-nil. If 'i' is nil, so will 'p' (preposition). The verb, 'v',
will never be nil. Note that 'p' can be nil even when 'i' is not,
in which case you should assume that the preposition is "to".
The implementation below behaves the same as the parser's default.
parseError2: function( v, d, p, i )
{
"I don't know how to << v.sdesc >> ";
if ( d )
"<< d.thedesc >>. ";
else
"anything << p ? p.sdesc : "to" >> << i.thedesc >>. ";
}
parseDefault(obj, prp): This function is called when the parser
is assuming a default object. If a default direct object is being
assumed, prp (the preposition) will be nil; otherwise, prp will have
the object corresponding to the preposition preceding the indirect
object. The implementation below provides the default behavior.
parseDefault: function( obj, prp )
{
"(";
if ( prp ) "<< prp.sdesc>> ";
obj.thedesc;
")";
}
Note that all three of these new functions are optional. If any
is omitted, the parser uses the default behavior, so existing games
will run unchanged. You can include any one without including the
others; these new functions are all independent. Note also that
the default parser behavior continues to use parseError the same
way it has since parseError was introduced; however, when these
new functions are provided, the corresponding parseError calls will
obviously no longer be made.
- New built-in function: objwords(num), which provides a list of
the actual words the user typed to refer to an object used in
the current command. The argument (num) is a number specifying
which object you're interested in: 1 for the direct object, or
2 for the indirect object. The return value is a list of strings;
the strings are the words used in the command. If a special
word, such as "it", "them", or "all", was used to specify the
object, the list will have a single element, which is the special
word used.
Examples:
>take all
objwords(1) -> ['all']
objwords(2) -> []
>put all in red box
objwords(1) -> ['all']
objwords(2) -> ['red' 'box']
>put blue box in it
objwords(1) -> ['blue' 'box']
objwords(2) -> ['it']
>put blue folder and green book in red box
blue folder:
objwords(1) -> ['blue' 'folder']
objwords(2) -> ['red' 'box']
green book:
objwords(1) -> ['green' 'book']
objwords(2) -> ['red' 'box']
This function could potentially be useful in such cases as
"ask actor about object", because it allows you to determine
much more precisely what the player is asking a