As well as fixing problems, these releases have introduced a range of new features into the Inform system; full details are provided in the associated Release Notes. Here is a brief summary, intended to supplement the DM4.
| Compiler constants |
| TARGET_ZCODE | is defined when targetting the Z-machine. |
| TARGET_GLULX | is defined when targetting Glulx. |
| WORDSIZE | is set to 2 when targetting the Z-machine, 4 when targetting Glulx. |
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| Statements |
| <...> and <<...>> | now accept an optional initial parameter: the actor who is to perform the command. <action noun second>; ! action is performed by the player
<<action noun second>>; ! (this is the current syntax)
<actor, action noun second>; ! action is performed by the specified actor
<<actor, action noun second>>; ! (this is the optional new format) |
| objectloop (x : expresssion) | is applied to every object x for which the expression is true. |
| (A) print rule | is similar to the existing (The) -– prints an object's indefinite article with its first letter capitalised. The printed article is "A", "An" or "Some" by default, or else taken from the object's 'article' property. |
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| Directives |
| Array...buffer | is similar to Array...string and Array...table. Array array buffer N;
Array array buffer expr1 expr2 ... exprN;
Array array buffer "string"; This creates a hybrid array of the form used by string.print_to_array and the new library routine PrintToBuffer( ), in which the first word array-->0 contains N and the following N bytes contain the specified expression values or string characters. A directive such as Array myArray buffer 100; initialises the first word myArray-->0 to 100 and the following 100 bytes myArray->WORDSIZE through myArray->(WORDSIZE+99) to zero. This behaviour is consistent with the handling of string and table arrays, as defined in the DM4. Note that Strict mode generates a warning if you use "->" to address an array of words, or "-->" to address an array of bytes. No such warnings are generated when addressing a buffer array, making this a useful declaration for any data structure which mixes byte and word values. |
| End | can be used in an Included file to immediately exit from that file, and the compilation continues normally. An End directive at the highest level terminates the compilation, as previously. |
| Include | is enhanced in two ways. A prefix of "?" means that the compilation should not fail if the specified file cannot be found. Second, the file to be included can be specified as a string constant. |
| If... | The directives which support conditional compilation --– #Ifdef, #Iftrue and so on -- can be used within Class and Object definitions. Additionally, these directives now support the logical operators &&, || and ~~.
Coding errors are ignored within a block of code which has been conditionally excluded from compilation -- for example, #Ifdef NOT_DEFINED; ... #Endif; or #Iftrue false; ... #Endif; |
| Replace | has an extended syntax: Replace library_routine new_name; This provides the same functionality as before; in addition, the existing library_routine is internally renamed to new_name, which means that the new version of library_routine which is provided as part of your game file can still invoke the original version which it is replacing. |
| Undef | this new directive causes its argument -- anything that can be tested with #Ifdef -- to become undefined from that point onwards. Previous references to the argument remain valid. |
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| Assembly language |
| @check_unicode and @print_unicode | are now supported. |
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| Switches |
| -I | (upper case I for 'Incompatible') treat obsolete usages as errors, not warnings. |
| -l | (lower case l for 'list') list Included filenames. |
| -On | optimise objectloops -- 0 = no optimisation, 1 = optimise for size, 2 = optimise for speed (default). |
| -v9 | compile to Version 9. |
| -Wn | is the minimum size in words of the Z-machine header extension table (default of 3). |
| -X | Infix is supported for Glulx targets. |
| -S, -D | Strict mode (which compiles run-time integrity checks) has been decoupled from Debug mode (which defines debugging verbs like TRACE and SHOWOBJ). By default, Strict mode is enabled (turn it off with -~S) and Debug mode is disabled (turn it on with -D). |
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| Compilation control |
| !% | is a special comment occurring on the very first line or lines of the source file, specifying Inform Command Language (ICL) commands to control the compilation. |
| +charset_map=file | to map proprietary code pages to ISO 8859 standards. |
| $DICT_WORD_SIZE=n | (default of 9). |
| $MAX_INCLUSION_DEPTH=n | (default of 5). |
| $MAX_SOURCE_FILES=n | (default of 256). |
| Library objects |
| LibraryExtensions | is used by extensions for initialisation and message interception. |
| n_obj, s_obj, etc | The word "wall" has been removed from the CompassDirection objects defined in English.h, whose names are now simply "north", "south", etc. |
| selfobj | includes an empty add_to_scope property. |
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| Library constants |
| LIBRARY_ENGLISH | is defined at the end of English.h. Alternatively, LIBRARY_FRENCH, LIBRARY_SWEDISH, etc. |
| LIBRARY_VERSION | is set to 612. |
| LIBRARY_STATE | is defined at the start of Parser.h as BEFORE_PARSER, and redefined at the end of Parser.h, VerbLib.h and Grammar.h as AFTER_PARSER, AFTER_VERBLIB and AFTER_GRAMMAR respectively. |
| MASTER_INCLUDE | defines the name of a Master Include File which itself Includes library extensions. The MIF is automatically included at the four values of LIBRARY_STATE. |
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| User-defined constants |
| CLR_ON=true | define as true to enable coloured output. |
| COMMENT_CHARACTER='char' | (default of '*'). The parser treats input lines beginning with this character as a comment, without attempting any further parsing. |
| NO_IMPLICIT_ACTIONS | define to disable implicit actions. |
| NO_SCORE | define to disable reporting of scores. |
| NO_TAKE_ALL | define to disable TAKE ALL command. |
| SERIAL_COMMAS | define to include 'serial' (aka 'Oxford') commas in lists. |
| SHORTNAMEBUF_LEN='n' | (default of 160). Specify the buffer size used for printing an object's short name. |
| START_MOVE=n | specify the initial value of turns counter. |
| TRADITIONAL_TAKE_ALL | define to disable TAKE of objects on supporters and in open containers, and to enable TAKE of animate, scenery and static objects. |
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| Variables |
| asking_player | is true when parser is asking player a disambiguation question. |
| before_first_turn | is true before first prompt is displayed. |
| keep_silent | set to 1 to suppress success messages, 2 to suppress all messages. |
| lookmode | defaults to 2 (VERBOSE). |
| sys_statusline_flag | set to 0 for statusline score, or to 1 by statusline time. |
| turns | is initialised to 0 rather than 1. |
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| Library routines |
| CapitRule(string) | prints the string with the first letter in upper case. Can also be used as a print rule. |
| Centre(string) | prints a single-line string approximately centrally between the left and right borders of the screen by preceding it with an appropriate number of spaces. |
| ClearScreen(selector) | if selector is 0, both statusline and main window are cleared; if selector is 1 only the statusline is cleared; if selector is 2 only the main window is cleared. |
| DecimalNumber(num) | prints num as a decimal number. |
| GameEpilogue( ) | runs before main 'play' loop. |
| GamePrologue( ) | runs after main 'play' loop/ |
| GetKeyBufLength(keybuffer) | returns the number of characters in the keybuffer (default is buffer). |
| KeyCharPrimitive | waits for a single key, and returns the character from 1-255 (or, for Glulx, one of the Glk special key codes). |
| KeyDelay(time) | waits time tenths of a second for a single key. If no key is pressed within that period it returns zero; otherwise it returns the character from 1-255. |
| LowerCase(char) | returns char in lower case (if it was alphabetic), or unchanged (otherwise). |
| MainWindow( ) | selects the main (buffered) text window for output. |
| MoveCursor(line, column) | selects the status line for output and moves the cursor to the given line and column within the status area, where line 1 is the top line and column 1 is the far left. |
| NumberWords(parsebuffer) | returns the number of parsed words in the parsebuffer (default is parse). |
| PrintCapitalised(arg1, arg2, no_break, no_caps, centred) | prints its arguments -- a string, an object's name, the value of an object's property, or a routine with up to one argument -- with the first letter in upper case. |
| PrintOrRunVar(arg, no_break) | if arg is an object, prints that object's name; if arg is a routine, runs that routine; if arg is a string, prints that string. |
| PrintToBuffer(array, arraylen, arg1, arg2, arg3) | prints its arguments -- a string, an object's name, the value of an object's property, or a routine with up to two arguments -- to the buffer array. |
| ScreenHeight( ) | returns the height in lines of the main window. |
| ScreenWidth( ) | returns the number of characters that can be printed in a monospaced font between the left and right borders of the currently selected window. |
| SetColour(fg, bg, selector) | sets the current foreground and background text colours, using the same codes as the @set_colour opcode in the Z-machine (1=default, 2=black, 3=red, 4=green etc.). |
| SetKeyBufLength(num, keybuffer) | resets the number of characters in the keybuffer (default is buffer). |
| StatusLineHeight(lines) | sets the height of the statusline in lines. |
| StringSize(string) | returns the number of characters in the string. |
| TaskScore(i) | returns the byte-value score associated with task i. |
| UpperCase(char) | returns char in upper case (if it was alphabetic), or unchanged (otherwise). |
| WordAddress(wordnum, parsebuffer, keybuffer) | returns the absolute address of parsed word wordnum in the keyboard buffer, now optionally accepts the address of the parsebuffer (default is parse) and the keybuffer (default is buffer). |
| WordLength(wordnum, parsebuffer) | returns the number of characters in parsed word wordnum in the input buffer, now optionally accepts the address of the parsebuffer (default is parse). |
| WordValue(wordnum, parsebuffer) | returns the dictionary value of parsed word wordnum in the input buffer; it optionally accepts the address of the parsebuffer (default is parse). |
| YesOrNo(flag) | if flag is true, status line is not refreshed. |
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| Object properties |
| before_implicit | is a local property invoked before various implicit actions. The property’s value should be a constant or a routine which returns: 0 to report "(first ...)" and then attempt to perform the action (this is what currently happens); 1 to attempt the action without first issuing the message, 2 to proceed with the requested action without first attempting the implied one. |
| compass_look | is a local property applicable to rooms, used with LOOK compass_direction. |
| description | can return 2 to suppress "The object is currently switched on|off" messages. |
| found_in | can be followed by a list of classes as well as objects. |
| invent | is invoked when building room descriptions as well as player inventories. |
| narrative_voice | is a local property applicable to the 'player' object; can be 1, 2 or 3. |
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| Object attributes |
| non_floating | is an alias for absent. |
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| Optional entry points |
| ObjectDoesNotFit(obj1,obj2) | should print a suitable message and return true if obj1 is too large or heavy to be placed in or on obj2; it should return false for the action to continue normally. |
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| Actions |
| ASK npc TO command and TELL npc TO command | are both synomymous with npc, command. |
| PRY, PRISE, PRIZE and LEVER | have been added. |
| RECORDING [ON|OFF] and REPLAY | are always available, irrespective of the DEBUG state. |
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| Fake actions |
| GoneFrom | is offered to the departure room's after property (after a successful movement, but before any arrival message is printed). |
