Chapter I: The Inform Language

§1   Routines

§2   The state of play

§3   Objects

Chapter II: Introduction to Designing

§4   ‘Ruins’ begun

Beginning to lay ‘Ruins’; including library files; the Initialise routine; some properties of mushrooms; name, description and initial; edible foodstuffs; introducing before and after rules; the stone steps.

§5   Introducing messages and classes

Recap of message-sending: a parrot; classes for treasure artifacts: the pygmy statuette, the honeycomb; how clashes are sorted out in class inheritance, additivity.

§6   Actions and reactions

Actions are attempts; generating them with <, <<; the actor, action, noun and second noun; the ## notation; actions fall into three groups; fake actions like ThrownAt; creating new actions, the Blorple example; how actions are processed, over ‘Before’, ‘During’ and ‘After’ stages.

§7   Infix and the debugging verbs

Three levels; general strategies; command lists and “recording”, “replay” and “random” debugging verbs; “showobj”, “tree”, “showverb”, “scope”; keeping watch of “actions”, “changes”, “messages”, “timers”; tracing the parser with “trace”; supernatural ability to “purloin”, “abstract”, “goto”, “gonear”; the Infix “; ”, “;give”, “;move”, “;remove”, “;examine”, “;watch”, “;inventory”; marking routines with a * to be watched.

Chapter III: The Model World

§8   Places and scenery

The Square Chamber of ‘Ruins’; what “you don't need to refer to”; static and scenery objects; spreading mist with found_in; α Canis Minoris; the five senses and reaction rules; rooms have before and after too.

§9   Directions and the map

Giving ‘Ruins’ a small map; n_to, d_to, etc.; when you cant_go; direction objects in the compass; not the same as direction properties.

§10   Food and drink

edible foodstuffs; the Drink action; difficulties with liquids.

§11   Clothing

Wear and Disrobe; wearable items of clothing; a jade face mask.

§12   Containers, supporters and sub-objects

Containers: container, supporter, capacity, open, openable; locks and keys: locked, lockable, with_key; LetGo and Receive to trap use of a container: a chasm; transparency and component parts.

§13   Doors

How to create a door; door_to, door_dir; when_open, when_closed; a stone door for ‘Ruins’; a two-way door, the ‘Advent’ grate; why door_dir is needed and how to trap every attempt to go through.

§14   Switchable objects

switchable and on: when_on, when_off; the Gotham City searchlight; a sodium lamp; describe taking precedence.

§15   Things to enter, travel in and push around

enterable objects: a slab altar; vehicles: KAR 1; special rule about the Go action when inside something enterable; the PushDir action: a huge pumice-stone ball; pushing up and down.

§16   Reading matter and consultation

The Consult action, “look up”; consult_from and consult_words: a dictionary of glyphs, Tyndale's Bible; making “read” and “examine” different.

§17   People and animals

animate objects and the life rule; a coiled snake and a mummified priest; Blofeld's reactions; talkable objects; some people are transparent.

§18   Making conversation

Orders are actions for other people; giving people their own grammars; untypeable verbs; several voice-activated machines; fake fake actions; telephony.

§19   The light and the dark

Light versus darkness is automatic; modifying the darkness; going from dark into dark and the DarkToDark entry point; rules on ‘when there is light’.

§20   Daemons and the passing of time

Daemons and the daemon property; starting and stopping them; background daemons; timers (fuses); time_left and time_out; each_turn events for places and nearby objects; the time of day; changing it with SetTime; on the status line; midnight, sunrise, sunset; the exact sequence of events at end-of-turn.

§21   Starting, moving, changing and killing the player

What Initialise should do; the location; initial restoration; teleportation and the PlayerTo routine; what happens when the room changes: NewRoom, initial for a room, visited; giving the player his own before rule; using ChangePlayer to transform him into any object; multi-character games; life and deadflag; the DeathMessage routine; resurrection and the AfterLife.

§22   Miscellaneous constants, scoring, quotations

Story and Headline; MAX_CARRIED; the automatic “sack object”; ‘amusing’ rewards for the victorious; two scoring systems: for places and items, or for completing tasks; rankings and PrintRank; automatic score notification and notify_mode; “objects” and “places” verbs, removable with NO_PLACES; boxed quotations.

§23   ‘Ruins’ revisited

Further examples to complete ‘Ruins’; a map and a step by step solution of the final game.

§24   The world model described

¶1. Substance – ¶2. Containment – ¶3. Space – ¶4. Sense – ¶5. Time – ¶6. Action.

§25   Extending and redefining the world model

Enriching the model; Egyptian amulets and their spells; making a new library file; the LibraryMessages system for changing messages like “Dropped.”; changing the prompt; the last resort of Replace directives; using the world model description; fire and flammability.

Chapter IV:   Describing and Parsing

§26   Describing objects and rooms

print (The) obj, ... (the) obj and so on; indefinite and definite article; proper nouns; the short_name of an object; invent strings and routines; exactly how inventory lines are printed; a matchbook; describe routines; exactly how rooms are described; Locale.

§27   Listing and grouping objects

The list-maker WriteListFrom; its style bitmap; examples: tall and wide inventories; grouping similar items together in lists: foodstuffs, Scrabble pieces and denominations of coin.

§28   How nouns are parsed

How name is used; a fried green tomato turning red; the parser breaks text into a stream of words; wn and NextWord; reading words as numbers or from their raw text; a parse_name routine is much more flexible than name; the ParseNoun entry point; distinguishing adjectives from nouns.

§29   Plural names for duplicated objects

Collections of indistinguishable objects; a bag of six coins; the plural property for printing out plurals; definition of ‘indistinguishable’; writing parse_name routines to allow plurals to be understood; class of crowns.

§30   How verbs are parsed

The parser's fundamental method; BeforeParsing entry point; the actor and verb word; synonyms for verbs; definitions of grammar, line and token; action_to_be; Verb directive: a simplified “take” grammar; meta verbs; grammar creates actions; creating an “xyzzy” verb; how to Extend grammar for an existing verb: pushing numbered buttons; priority: replace, first, last; splitting synonymous verbs apart with Extend only; the UnknownVerb and PrintVerb entry points.

§31   Tokens of grammar

Full list of grammar tokens; prepositions; noun and held; implicit taking; tokens allowing multiple objects like “all”; filtering out nouns by attribute: “use” verb; and by general routine: “free” verb; parsing numbers: “type” verb, ParseNumber; general parsing routines; reading from the parser's raw text buffer and parse table; exercises, including French, telephone and floating-point numbers, times of day, adding a third parameter to a grammar line.

§32   Scope and what you can see

The definition of ‘in scope’; touchability is stricter than scope; answering questions: “what is a grue”; scope=... tokens with programmable scope; scope_stage, ScopeWithin and PlaceInScope; changing the global definition of ‘in scope’ using InScope; scope_reason; looping over and testing scope; making the rules more sensitive to darkness; a long room divided by a glass wall; the add_to_scope property for component parts of containers.

§33   Helping the parser out of trouble

Parser error messages and ParserError; ambiguity-resolution and influencing it with ChooseObjects; making “eat” prefer edible objects; redefining “all”; exactly how ambiguities are resolved.

Chapter V: Natural Language

§34   Linguistics and the Inform parser

¡Bienvenido a Aventura!; Informese; commands, verb phrases, prepositions, noun phrases, gender-number-animation (GNA), descriptors, nouns, pronouns; example of parsing; grammatical features not present in Informese.

§35   Case and parsing noun phrases

Flexion and cases; parsing inflected noun phrases; for example, Old English dative word-endings.

§36   Parsing non-English languages

Compromises; accented characters at the keyboard?; dialects; language definition files; Zcharacter and the customisation of ZSCII; specifying pronouns and descriptors; translating natural languages to Informese.

§37   Names and messages in non-English languages

Gender-number-animation of short names; agreement with articles and cases; contraction forms and articles; library messages of all kinds.

Chapter VI:   Using the Compiler

§38   Controlling compilation from within

Include; conditional compilation: If..., Ifnot, Endif; Message; linking in the library; writing new modules to link in; serial and release numbers.

§39   Controlling compilation from without

Switches; memory settings; pathname variables; Inform Control Language (ICL).

§40   All the Inform error messages

Fatal errors; errors, including linker and assembler errors; warnings, including obsolete usage warnings.

Chapter VII:   The Z-Machine

§41   Architecture and assembly

ZIL, Inform and the Z-machine; its Versions; assembly language; store and branch opcodes, labels; memory map and stack.

§42   Devices and opcodes

The Standard for interpreters; input and output streams; the Version 5 and Version 6 screen models; colours, windows and status lines; interrupt countdowns; pictures; sounds; keyboard reading with timed interrupts; terminating characters; the mouse; menus; loading and saving auxiliary files; throwing and catching stack frames.

§43   Pictures, sounds, blurbs and Blorb

What a Blorb file is; the perlBlorb utility program; blurb files; palette, resolution, scaling; specifying what sounds and pictures belong to a story file.

§44   Case study: a library file for menus

Invisiclues; basic design; the Option class; the Menu class; the SwitchOption class.

§45   Limitations and getting around them

Story file size; readable memory size; grammar; vocabulary; dictionary resolution; objects, attributes, properties, names; function and message arguments; recursion and stack usage; abbreviations in text.

Chapter VIII: The Craft of Adventure

§46   A brief history of interactive fiction

§47   Realities and origins

Fictional backgrounds; crimes against mimesis; historical research; book adaptations.

§48   A triangle of identities

Player, protagonist and narrator; participatory magic; the overture and other narrated text.

§49   Structure

Size and density; the prologue, middle game and end game; wide versus narrow; lattice diagrams, including one for ‘Ruins’.

§50   The design of puzzles

General remarks on good and bad puzzles; mazes, light sources, capacity and exhaustion, timed puzzles, utility objects, keys and doors, machinery and vehicles, fire, water, air, earth, plants, animals, monsters, people, ropes and chains, riddles, decipherment puzzles; clues, luck and accidental solutions; optional and multiple solutions; rewards.

§51   The room description

Examples of good, mediocre and poor description; how much space is one location?; variable descriptions; outdoor games; differing perspectives.

§52   Finishing

Scoring systems; responding to wrong guesses; examples of typical bugs; play-testing and editing; concluding homily.




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