Examples in Thematic Order

| Examples in Thematic Order |

Preface

1
| Example About the examples An explanation of the examples in this documentation, and the asterisks attached to them. Click the heading of the example, or the example number, to reveal the text. |
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11
| Example Midsummer Day A few sentences laying out a garden together with some things which might be found in it. |
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Disenchantment Bay

13
| Example Disenchantment Bay 1 A running example in this chapter, Disenchantment Bay, involves chartering a boat. This is the first step: creating the cabin. |
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14
| Example Disenchantment Bay 2 Disenchantment Bay: creating some of the objects in the cabin's description. |
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16
| Example Disenchantment Bay 3 Disenchantment Bay: adding a view of the glacier. |
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17
| Example Disenchantment Bay 4 Disenchantment Bay: fleshing out the descriptions of things on the boat. |
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19
| Example Disenchantment Bay 5 Disenchantment Bay: adding the door and the deck to our charter boat. |
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22
| Example Disenchantment Bay 6 Disenchantment Bay: locking up the charter boat's fishing rods. |
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24
| Example Disenchantment Bay 7 Disenchantment Bay: making the radar and instruments switch on and off. |
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27
| Example Disenchantment Bay 8 Disenchantment Bay: a pushable chest of ice for the boat. |
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29
| Example Disenchantment Bay 9 Disenchantment Bay: enter the charter boat's Captain. |
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32
| Example Disenchantment Bay 10 Disenchantment Bay: things for the player and the characters to wear and carry. |
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33
| Example Disenchantment Bay 11 Disenchantment Bay: making a holdall of the backpack. |
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35
| Example Disenchantment Bay 12 A final trip to Disenchantment Bay: the scenario turned into a somewhat fuller scene, with various features that have not yet been explained. |
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Information Only

383
| Example Backus-Naur form for rules The full grammar Inform uses to parse rule definitions, in a standard computer-science notation. |
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223
| Example Formal syntax of sentences A more formal description of the sentence grammar used by Inform for both assertions and conditions. |
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243
| Example Mathematical view of relations Some notes on relations from a mathematical point of view, provided only to clarify some technicalities for those who are interested. |
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244
| Example Graph-theory view of relations Some notes on relations from the point of view of graph theory. |
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403
| Example About Inform's regular expression support Some footnotes on Inform's regular expressions, and how they compare to those of other programming languages. |
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Varying What Is Written

178
| Example M. Melmoth's Duel Three basic ways to inject random or not-so-random variations into text. |
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169
| Example Ahem Writing a phrase, with several variant forms, whose function is to follow a rule several times. |
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71
| Example Fifty Ways to Leave Your Larva Using text substitution to make characters reply differently under the same circumstances. |
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72
| Example Fifty Times Fifty Ways Writing your own rules for how to carry out substitutions. |
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428
| Example Curare A phrase that chooses and names the least-recently selected item from the collection given, allowing the text to cycle semi-randomly through a group of objects. |
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294
| Example Straw Into Gold Creating a Rumpelstiltskin character who is always referred to as "dwarf", "guy", "dude", or "man" -- depending on which the player last used -- until the first time the player refers to him as "Rumpelstiltskin". |
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440
| Example Odins Making [is-are] and [it-they] say tokens that will choose appropriately based on the last object mentioned. |
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60
| Example Ballpark A new "to say" definition which allows the author to say "[a number in round numbers]" and get verbal descriptions like "a couple of" or "a few" as a result. |
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174
| Example Numberless A simple exercise in printing the names of random numbers, comparing the use of "otherwise if...", a switch statement, or a table-based alternative. |
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330
| Example Prolegomena Replacing precise numbers with "some" or other quantifiers when too many objects are clustered together for the player to count at a glance. |
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444
| Example Blink Making a "by atmosphere" token, allowing us to design our own text variations such as "[one of]normal[or]gloomy[or]scary[by atmosphere]". |
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408
| Example Blackout Filtering the names of rooms printed while in darkness. |
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401
| Example Rocket Man Using case changes on any text produced by a "to say..." phrase. |
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Varying What Is Read

18
| Example Laura Some general advice about creating objects with unusual or awkward names, and a discussion of the use of printed names. |
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41
| Example Vouvray Adding synonyms to an entire kind of thing. |
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10
| Example First Name Basis Allowing the player to use different synonyms to refer to something. |
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312
| Example Quiz Show In this example by Mike Tarbert, the player can occasionally be quizzed on random data from a table; the potential answers will only be understood if a question has just been asked. |
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360
| Example North by Northwest Creating additional compass directions between those that already exist (for instance, NNW) -- and dealing with an awkwardness that arises when the player tries to type "north-northwest". The example demonstrates a way around the nine-character limit on parsed words. |
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314
| Example Pot of Petunias Responding sensibly to a pot of petunias falling from the sky. |
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Using the Player's Input

307
| Example Terracottissima Maxima Flowerpots with textual names that might change during play. |
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411
| Example Mr. Burns' Repast Letting the player guess types for an unidentifiable fish. |
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367
| Example Xot Storing an invalid command to be repeated as text later in the game. |
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409
| Example Igpay Atinlay A pig Latin filter for the player's commands. |
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Room Descriptions

321
| Example Ant-Sensitive Sunglasses What are activities good for? Controlling output when we want the same action to be able to produce very flexible text depending on the state of the world -- in this case, making highly variable room description and object description text. |
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344
| Example Priority Lab A debugging rule useful for checking the priorities of objects about to be listed. |
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345
| Example Low Light An object that is only visible and manipulable when a bright light fixture is on. |
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343
| Example The Eye of the Idol A systematic way to allow objects in certain places to be described in the room description body text rather than in paragraphs following the room description, and to control whether supporters list their contents or not. |
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341
| Example Rip Van Winkle A simple way to allow objects in certain places to be described in the room description body text rather than in paragraphs following the room description. |
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348
| Example Copper River Manipulating room descriptions so that only interesting items are mentioned, while objects that are present but not currently useful to the player are ignored. |
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3
| Example Slightly Wrong A room whose description changes slightly after our first visit there. |
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152
| Example Infiltration A room whose description changes depending on the number of times the player has visited. |
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147
| Example Night Sky A room which changes its description depending on whether an object has been examined. |
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Map

4
| Example Port Royal 1 A partial implementation of Port Royal, Jamaica, set before the earthquake of 1692 demolished large portions of the city. |
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7
| Example Port Royal 2 Another part of Port Royal, with less typical map connections. |
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9
| Example Port Royal 3 Division of Port Royal into regions. |
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101
| Example A&E Using regions to block access to an entire area when the player does not carry a pass, regardless of which entrance he uses. |
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125
| Example Bee Chambers A maze with directions between rooms randomized at the start of play. |
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134
| Example Zork II A "Carousel Room", as in Zork II, where moving in any direction from the room leads (at random) to one of the eight rooms nearby. |
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38
| Example Prisoner's Dilemma A button that causes a previously non-existent exit to come into being. |
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77
| Example All Roads Lead to Mars Layout where the player is allowed to wander any direction he likes, and the map will arrange itself in order so that he finds the correct "next" location. |
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276
| Example Indirection Renaming the directions of the compass so that "white" corresponds to north, "red" to east, "yellow" to south, and "black" to west. |
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39
| Example The World of Charles S. Roberts Replacing the ordinary compass bearings with a set of six directions to impose a hexagonal rather than square grid on the landscape. |
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Position Within Rooms

63
| Example When? A door whose description says "...leads east" in one place and "...leads west" in the other. |
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65
| Example Whence? A kind of door that always automatically describes the direction it opens and what lies on the far side (if that other room has been visited). |
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Continuous Spaces and The Outdoors

308
| Example Whither? A door whose description says where it leads; and which automatically understands references such as "the west door" and "the east door" depending on which direction it leads from the location. |
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128
| Example Higher Calling All doors in the game automatically attempt to open if the player approaches them when they are closed. |
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150
| Example Elsie A door that closes automatically one turn after the player opens it. |
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23
| Example Neighborhood Watch A locked door that can be locked or unlocked without a key from one side, but not from the other. |
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21
| Example Garibaldi 1 Providing a security readout device by which the player can check on the status of all doors in the game. |
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236
| Example Wainwright Acts A technical note about checking the location of door objects when characters other than the player are interacting with them. |
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42
| Example Something Narsty A staircase always open and never openable. |
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88
| Example Hayseed A refinement of our staircase kind which can be climbed. |
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Doors, Staircases, and Bridges

106
| Example One Short Plank A plank bridge which breaks if the player is carrying something when he goes across it. Pushing anything over the bridge is forbidden outright. |
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6
| Example Starry Void Creating a booth that can be seen from the outside, opened and closed, and entered as a separate room. |
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198
| Example Further Reasons Why All Poets Are Liars The young William Wordsworth, pushing a box about in his room, must struggle to achieve a Romantic point of view. |
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212
| Example Carnivale An alternative to backdrops when we want something to be visible from a distance but only touchable from one room. |
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213
| Example Eddystone Creating new commands involving the standard compass directions. |
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215
| Example Waterworld A backdrop which the player can examine, but cannot interact with in any other way. |
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80
| Example A View of Green Hills A LOOK [direction] command which allows the player to see descriptions of the nearby landscape. |
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62
| Example Tiny Garden A lawn made up of several rooms, with part of the description written automatically. |
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352
| Example Rock Garden A simple open landscape where the player can see between rooms and will automatically move to touch things in distant rooms. |
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353
| Example Stately Gardens An open landscape where the player can see landmarks in nearby areas, with somewhat more complex room descriptions than the previous example, and in which we also account for size differences between things seen at a distance. |
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79
| Example Hotel Stechelberg Signposts such as those provided on hiking paths in the Swiss Alps, which show the correct direction and hiking time to all other locations. |
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Windows

20
| Example Escape Window that can be climbed through or looked through. |
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116
| Example Vitrine An electrochromic window that becomes transparent or opaque depending on whether it is currently turned on. |
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261
| Example Port Royal 4 A cell window through which the player can see people who were in Port Royal in the current year of game-time. |
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217
| Example Dinner is Served A window between two locations. When the window is open, the player can reach through into the other location; when it isn't, access is barred. |
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181
| Example A Haughty Spirit Windows overlooking lower spaces which will prevent the player from climbing through if the lower space is too far below. |
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Lighting

49
| Example The Undertomb 2 Flickering lantern-light effects added to the Undertomb. |
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333
| Example Zorn of Zorna Light levels vary depending on the number of candles the player has lit, and this determines whether or not he is able to examine detailed objects successfully. |
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301
| Example Hymenaeus Understanding "flaming torch" and "extinguished torch" to refer to torches when lit and unlit. |
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25
| Example Down Below A light switch which makes the room it is in dark or light. |
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194
| Example The Dark Ages Revisited An electric light kind of device which becomes lit when switched on and dark when switched off. |
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338
| Example Reflections Emphasizing the reflective quality of shiny objects whenever they are described in the presence of the torch. |
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334
| Example Hohmann Transfer Changing the way dark rooms are described to avoid the standard Inform phrasing. |
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335
| Example Four Stars An elaboration of the idea that when light is absent, the player should be given a description of what he can smell and hear, instead. |
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350
| Example Peeled Two different approaches to adjusting what the player can interact with, compared. |
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81
| Example Unblinking Finding a best route through light-filled rooms only, leaving aside any that might be dark. |
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280
| Example Cloak of Darkness Implementation of "Cloak of Darkness", a simple example game that for years has been used to demonstrate the features of IF languages. |
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Sounds

48
| Example The Undertomb 1 A small map of dead ends, in which the sound of an underground river has different strengths in different caves. |
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95
| Example The Art of Noise Things are all assigned their own noise (or silence). Listening to the room in general reports on all the things that are currently audible. |
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349
| Example Scope for listening different from scope for seeing Using "deciding the scope" to change the content of lists such as "the list of audible things which can be touched by the player". |
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Passers-By, Weather and Astronomical Events

131
| Example Weathering The automatic weather station atop Mt. Pisgah shows randomly fluctuating temperature, pressure and cloud cover. |
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132
| Example Uptown Girls A stream of random pedestrians who go by the player. |
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157
| Example Full Moon Random atmospheric events which last the duration of a scene. |
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120
| Example Orange Cones Creating a traffic backdrop that appears in all road rooms except the one in which the player has laid down orange cones. |
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164
| Example Night and Day Cycling through a sequence of scenes to represent day and night following one another during a game. |
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144
| Example Totality To schedule an eclipse of the sun, which involves a number of related events. |
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The Passage Of Time

142
| Example Situation Room Printing the time of day in 24-hour time, as in military situations. |
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249
| Example Zqlran Era 8 Creating an alternative system of time for our game, using new units. |
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391
| Example Uptempo Adjust time advancement so the game clock moves fifteen minutes each turn. |
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183
| Example The Hang of Thursdays Turns take a quarter day each, and the game rotates through the days of the week. |
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397
| Example Timeless A set of actions which do not take any game time at all. |
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400
| Example Endurance Giving different actions a range of durations using a time allotment rulebook. |
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363
| Example The Big Sainsbury's Making implicit takes add a minute to the clock, just as though the player had typed TAKE THING explicitly. |
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Scripted Scenes

159
| Example Day One A scene which plays through a series of events in order, then ends when the list of events is exhausted. |
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155
| Example Entrapment A scene in which the player is allowed to explore as much as he likes, but another character strolls in as soon as he has gotten himself into an awkward or embarrassing situation. |
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162
| Example The Prague Job Scenes used to provide pacing while the player goes through his possessions. |
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160
| Example Bowler Hats and Baby Geese Creating a category of scenes that restrict the player's behavior. |
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Event Scheduling

141
| Example IPA Shops which each have opening and closing hours, so that it is impossible to go in at the wrong times, and the player is kicked out if he overstays his welcome. |
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340
| Example Air Conditioning is Standard Uses "writing a paragraph about" to make person and object descriptions that vary considerably depending on what else is going on in the room, including some randomized NPC interactions with objects or with each other. |
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146
| Example Hour of the Wren Allowing the player to make an appointment, which is then kept. |
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Scene Changes

156
| Example Age of Steam The railway-station examples so far put together into a short game called "Age of Steam". |
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119
| Example Meteoric I and II A meteor in the night sky which is visible from many rooms, so needs to be a backdrop, but which does not appear until 11:31 PM. |
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163
| Example Entrevaux Organizing the game by scenes, where each scene has a location and prop lists so that it can be set up automatically. |
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158
| Example Space Patrol - Stranded on Jupiter! We'll be back in just a moment, with more exciting adventures of the... Space Patrol! |
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Flashbacks

165
| Example Pine 3 Pine: Allowing the player to visit aspects of the past in memory and describe these events to the princess, as a break from the marriage-proposal scene. |
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167
| Example Pine 4 Pine: Adding a flashback scene that, instead of repeating endlessly, repeats only until the Princess has understood the point. |
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Plot Management

209
| Example Fate Steps In Fate entity which attempts to make things happen, by hook or by crook, including taking preliminary actions to set the player up a bit. |
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The Human Body

56
| Example The Night Before Instructing Inform to prefer different interpretations of EXAMINE NOSE, depending on whether the player is alone, in company, or with Rudolph the Red-nosed Reindeer. |
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245
| Example rBGH The player character's height is selected randomly at the start of play. |
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381
| Example Slouching A system of postures allowing the player and other characters to sit, stand, or lie down explicitly or implicitly on a variety of enterable supporters or containers, or in location. |
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Traits Determined By the Player

405
| Example Identity Theft Allowing the player to enter a name to be used for the player character during the game. |
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441
| Example Pink or Blue Asking the player to select a gender to begin play. |
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298
| Example Baritone, Bass Letting the player pick a gender (or perhaps other characteristics) before starting play. |
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Characterization

73
| Example Finishing School The "another" adjective for rules such as "in the presence of another person". |
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109
| Example Dearth and the Maiden Our heroine, fallen among gentleman highwaymen, is restrained by her own modesty and seemliness. |
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84
| Example Bad Hair Day Change the player's appearance in response to EXAMINE ME. |
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Background

266
| Example Merlin A REMEMBER command which accepts any text and looks up a response in a table of recollections. |
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290
| Example One of Those Mornings A FIND command that allows the player to find a lost object anywhere |
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Memory and Knowledge

310
| Example Puncak Jaya When a character is not visible, responding to such commands as EXAMINE PETER and PETER, HELLO with a short note that the person in question is no longer visible. |
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149
| Example Tense Boxing An overview of all the variations of past and present tenses, and how they might be used. |
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148
| Example Zero A box which called "horribly heavy box" after the player has tried to take it the first time. |
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346
| Example Casino Banale Creating room descriptions and object descriptions that change as the player learns new facts and pieces things together. |
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Viewpoint

121
| Example Terror of the Sierra Madre Multiple player characters who take turns controlling the action. |
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445
| Example Uncommon Ground Making a "by viewpoint" token, allowing us to design our own text variations such as "[show to yourself]quaint[to Lolita]thrilling[to everyone else]squalid[end show]" depending on the identity of the player at the moment. |
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51
| Example The Crane's Leg 1 A description text that automatically highlights the ways in which the object differs from a standard member of its kind. |
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377
| Example The Crane's Leg 2 A description text generated based on the propensities of the player-character, following different rulebooks for different characters. |
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Modifying Existing Commands

214
| Example Slogar's Revenge Creating an amulet of tumblers that can be used to lock and unlock things even when it is worn, overriding the usual requirement that keys be carried. |
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Looking

2
| Example Verbosity 1 Making rooms give full descriptions each time we enter, even if we have visited before. |
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380
| Example Verbosity 2 Making rooms give full descriptions each time we enter, even if we have visited before, and disallowing player use of BRIEF and SUPERBRIEF. |
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Examining

323
| Example Crusoe Adding a "printing the description of something" activity. |
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43
| Example Odin Replacing "You see nothing special..." with a different default message for looking at something nondescript. |
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284
| Example The Left Hand of Autumn The possibility of using a [things] token opens up some interesting complications, because we may want actions on multiple items to be reported differently from actions on just one. Here we look at how to make a multiple examination command that describes groups in special ways. |
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68
| Example Beekeeper's Apprentice Making the SEARCH command examine all the scenery in the current location. |
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Looking Under and Hiding

98
| Example Beachfront An item that the player can't interact with until he has found it by searching the scenery. |
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233
| Example Beneath the Surface An "underlying" relation which adds to the world model the idea of objects hidden under other objects. |
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218
| Example Flashlight Visibility set so that looking under objects produces no result unless the player has a light source to shine there (regardless of the light level of the room). |
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173
| Example Matreshka A SEARCH [room] action that will open every container the player can see, stopping only when there don't remain any that are closed, unlocked, and openable. |
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Inventory

177
| Example Equipment List Overview of all the phrase options associated with listing, and examples of how to change the inventory list into some other standard formats. |
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64
| Example Persephone Separate the player's inventory listing into two parts, so that it says "you are carrying..." and then (if the player is wearing anything) "You are also wearing...". |
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414
| Example Oyster Wide Shut Replacing Inform's default printing of properties such as "(closed)", "(open and providing light)", etc., with our own, more flexible variation. |
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204
| Example Trying Taking Manhattan Replacing the inventory reporting rule with another which does something slightly different. |
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Taking, Dropping, Inserting and Putting

15
| Example Replanting Changing the response when the player tries to take something that is scenery. |
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200
| Example Removal TAKE expanded to give responses such as "You take the book from the shelf." or "You pick up the toy from the ground." |
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202
| Example Croft Adding special reporting and handling for objects dropped when the player is on a supporter, and special entering rules for moving from one supporter to another. |
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225
| Example Celadon Using the enclosure relation to let the player drop things which he only indirectly carries. |
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90
| Example Morning After When the player picks something up which he hasn't already examined, the object is described. |
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86
| Example Democratic Process Make PUT and INSERT commands automatically take objects if the player is not holding them. |
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87
| Example Sand Extend PUT and INSERT handling to cases where multiple objects are intended at once. |
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Going, Pushing Things in Directions

107
| Example Zorb Replacing the message the player receives when attempting to push something that isn't pushable, and also to remove the restriction that objects cannot be pushed up or down. |
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102
| Example Bumping into Walls Offering the player a list of valid directions if he tries to go in a direction that leads nowhere. |
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5
| Example Up and Up Adding a short message as the player approaches a room, before the room description itself appears. |
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100
| Example Veronica An effect that occurs only when the player leaves a region entirely. |
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199
| Example The Second Oldest Problem Adapting the going action so that something special can happen when going from a dark room to another dark room. |
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105
| Example Mattress King Adding extra phrasing to the action to PUSH something in a direction. |
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379
| Example Saint Eligius Adding a first look rule that comments on locations when we visit them for the first time, inserting text after objects are listed but before any "every turn" rules might occur. |
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295
| Example Misadventure A going by name command which does respect movement rules, and accepts names of rooms as commands. |
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296
| Example Safari Guide The same functionality, but making the player continue to move until he reaches his destination or a barrier, handling all openable doors on the way. |
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108
| Example Provenance Unknown Allowing something like PUSH TELEVISION EAST to push the cart on which the television rests. |
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103
| Example Polarity A "go back" command that keeps track of the direction from which the player came, and sends him back. |
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358
| Example Minimal Movement Supplying a default direction for "go", so that "leave", "go", etc., are always interpreted as "out". |
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179
| Example Owen's Law OUT always means "move to an outdoors room, or else to a room with more exits than this one has"; IN always means the opposite. |
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246
| Example Wonderland Hiking Mount Rainier, with attention to which locations are higher and which lower than the present location. |
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Entering and Exiting, Sitting and Standing

299
| Example Lies Commands to allow the player to lie down in three different ways. |
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278
| Example Anchorite By default, Inform understands GET OFF, GET UP, or GET OUT when the player is sitting or standing on an enterable object. We might also want to add GET DOWN and DOWN as exit commands, though: |
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206
| Example Get Axe Changing the check rules to try automatically leaving a container before attempting to take it. (And arranging things so that other people will do likewise.) |
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Waiting, Sleeping

374
| Example Nine AM Appointment A WAIT [number] MINUTES command which advances through an arbitrary number of turns. |
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375
| Example Delayed Gratification A WAIT UNTIL [time] command which advances until the game clock reaches the correct hour. |
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45
| Example Change of Basis Implementing sleeping and wakeful states. |
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Magic Words

275
| Example XYZZY Basics of adding a new command reviewed, for the case of the simple magic word XYZZY. |
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Remembering, Converting and Combining Actions

89
| Example Fine Laid Making writing that can be separately examined from the paper on which it appears, but which directs all other actions to the paper. |
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92
| Example Lucy Redirecting a question about one topic to ask about another. |
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220
| Example Cactus Will Outlive Us All For every character besides the player, there is an action that will cause that character to wither right up and die. |
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422
| Example I Didn't Come All The Way From Great Portland Street In this fiendishly difficult puzzle, which may perhaps owe some inspiration to a certain BBC Radio panel game (1967-), a list is used as a set of actions to help enforce the rule that the player must keep going for ten turns without hesitation, repetition, or deviating from the subject on the card. |
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419
| Example Leopard-skin A maze that the player can escape if he performs an exact sequence of actions. |
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222
| Example Anteaters The player carries a gizmo that is able to record actions performed by the player, then force him to repeat them when the gizmo is dropped. This includes storing actions that apply to topics, as in "look up anteater colonies in the guide". |
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Actions on Multiple Objects

283
| Example Shawn's Bad Day Allowing the player to EXAMINE ALL. |
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399
| Example Escape from the Seraglio Replacing the usual response to TAKE ALL so that instead of output such as "grapes: Taken. orange: Taken.", Inform produces variable responses in place of "grapes:". |
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417
| Example Formicidae Manipulating the order in which items are handled after TAKE ALL. |
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420
| Example The Facts Were These Creating a variant GIVE action that lets the player give multiple objects simultaneously with commands like GIVE ALL TO ATTENDANT or GIVE THREE DOLLARS TO ATTENDANT or GIVE PIE AND HAT TO ATTENDANT. The attendant accepts the gifts only if their total combined value matches some minimum amount. |
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Alternate Default Messages

382
| Example We Replacing the standard action report rules to reflect our own design. |
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Clarification and Correction

279
| Example Alpaca Farm A generic USE action which behaves sensibly with a range of different objects. |
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355
| Example Apples Prompting the player on how to disambiguate otherwise similar objects. |
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356
| Example Walls and Noses Responding to "EXAMINE WALL" with "In which direction?", and to "EXAMINE NOSE" with "Whose nose do you mean, Frederica's, Betty's, Wilma's or your own?" |
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413
| Example Cave-troll Determining that the command the player typed is invalid, editing it, and re-examining it to see whether it now reads correctly. |
WI

366
| Example WXPQ Creating a more sensible parser error than "that noun did not make sense in this context". |
WI

Alternatives To Standard Parsing

361
| Example Cloves Accepting adverbs anywhere in a command, registering what the player typed but then cutting them out before interpreting the command. |
WI

359
| Example Fragment of a Greek Tragedy Responding to the player's input based on keywords only, and overriding the original parser entirely. |
WI

293
| Example Down in Oodville Offering the player a choice of numbered options at certain times, without otherwise interfering with his ability to give regular commands. |
WI

Getting Acquainted

30
| Example Belfry You can see a bat, a bell, some woodworm, William Snelson, the sexton's wife, a bellringer and your local vicar here. |
WI

31
| Example Gopher-wood Changing the name of a character in the middle of play, removing the article. |
WI

303
| Example Peers The peers of the English realm come in six flavours - Baron, Viscount, Earl, Marquess, Duke and Prince - and must always be addressed properly. While a peerage is for life, it may at the royal pleasure be promoted. |
WI

237
| Example A Humble Wayside Flower Relations track the relationships between one character and another. Whenever the player meets a relative of someone he already knows, he receives a brief introduction. |
WI

238
| Example Meet Market A case in which relations give characters multiple values of the same kind. |
WI

135
| Example Clueless A murderer for the mystery is selected randomly at the beginning of the game. |
WI

Liveliness

67
| Example Camp Bethel Creating characters who change their behavior from turn to turn, and a survey of other common uses for alternative texts. |
WI

153
| Example Annoyotron Jr A child who after a certain period in the car starts asking annoying questions. |
WI

76
| Example Lean and Hungry A thief who will identify and take any valuable thing lying around that he is able to touch. |
WI

140
| Example Text Foosball A game of foosball which relies heavily on every-turn rules. |
WI

Reactive Characters

96
| Example Zodiac Several variations on "doing something other than...", demonstrating different degrees of restriction. |
WI

186
| Example Police State Several friends who obey you; a policeman who doesn't (but who takes a dim view of certain kinds of antics). |
WI

196
| Example Noisemaking Creating a stage after the report stage of an action, during which other characters may observe and react. |
WI

36
| Example Search and Seizure A smuggler who has items, some of which are hidden. |
WI

154
| Example Pine 1 Pine: Using a scene to watch for the solution of a puzzle, however arrived-at by the player. |
WI

112
| Example A Day For Fresh Sushi A complete story by Emily Short, called "A Day for Fresh Sushi", rewritten using Inform 7. Noteworthy is the snarky commenter who remarks on everything the player does, but only the first time each action is performed. |
WI

82
| Example Revenge of the Fussy Table A small game about resentful furniture and inconvenient objects. |
WI

Barter and Exchange

378
| Example Bribery A GIVE command that gets rid of Inform's default refusal message in favor of something a bit more sophisticated. |
WI

207
| Example Barter Barter Allowing characters other than the player to give objects to one another, accounting for the possibility that some items may not be desired by the intended recipients. |
WI

Combat and Death

191
| Example Red Cross A DIAGNOSE command which allows the player to check on the health of someone. |
WI

130
| Example Lanista 1 Very simple randomized combat in which characters hit one another for a randomized amount of damage. |
WI

282
| Example Lanista 2 Randomized combat in which the damage done depends on what weapons the characters are wielding, and in which an ATTACK IT WITH action is created to replace regular attacking. Also folds a new DIAGNOSE command into the system. |
WI

201
| Example Puff of Orange Smoke A system in which every character has a body, which is left behind when the person dies; attempts to do something to the body are redirected to the person while the person is alive. |
WI

127
| Example Technological Terror A ray gun which destroys objects, leaving their component parts behind. |
WI

113
| Example Don Pedro's Revenge Combat scenario in which the player's footing and position changes from move to move, and the command prompt also changes to reflect that. |
WI

Getting Started with Conversation

110
| Example Mimicry People who must be greeted before conversation can begin. |
WI

316
| Example The Gorge at George If the player tries to TALK TO a character, suggest alternative modes of conversation. |
WI

Saying Simple Things

91
| Example Sybil 1 Direct all ASK, TELL, and ANSWER commands to ASK, and accept multiple words for certain cases. |
WI

93
| Example Sybil 2 Making the character understand YES, SAY YES TO CHARACTER, TELL CHARACTER YES, ANSWER YES, and CHARACTER, YES. |
WI

171
| Example Proposal Asking the player a yes/no question which he must answer, and another which he may answer or not as he chooses. |
WI

286
| Example Nameless ASKing someone about an object rather than about a topic. |
WI

Saying Complicated Things

270
| Example Farewell People who respond to conversational gambits, summarize what they said before if asked again, and provide recap of conversation that is past. |
WI

271
| Example Sweeney A conversation where each topic may have multiple questions and answers associated with it, and where a given exchange can lead to new additions to the list. |
WI

168
| Example Cheese-makers Scenes used to control the way a character reacts to conversation and comments, using a TALK TO command. |
WI

362
| Example Complimentary Peanuts A character who responds to keywords in the player's instructions and remarks, even if there are other words included. |
WI

Character Emotion

170
| Example Ferragamo Again Using the same phrase to produce different results with different characters. |
WI

388
| Example Being Peter A set of rules determining the attitude a character will take when asked about certain topics. |
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Character Knowledge and Reasoning

242
| Example Murder on the Orient Express A number of sleuths (the player among them) find themselves aboard the Orient Express, where a murder has taken place, and one of them is apparently the culprit. Naturally they do not agree on whom, but there is physical evidence which may change their minds... |
WI

268
| Example Questionable Revolutions An expansion on the previous idea, only this time we store information and let characters answer depending on their expertise in a given area. |
WI

267
| Example The Queen of Sheba Allowing the player to use question words, and using that information to modify the response given by the other character. |
WI

235
| Example The Problem of Edith A conversation in which the main character tries to build logical connections between what the player is saying now and what went immediately before. |
WI

328
| Example Chronic Hinting Syndrome Using name-printing rules to keep track of whether the player knows about objects, and also to highlight things he might want to follow up. |
WI

Characters Following a Script

161
| Example Pine 2 Pine: Adding a conversation with the princess, in which a basic set of facts must be covered before the scene is allowed to end. |
WI

415
| Example Robo 1 A robot which watches and records the player's actions, then tries to repeat them back in the same order when he is switched into play-back mode. |
WI

418
| Example Robo 2 A robot which watches and records the player's actions, then tries to repeat them back in the same order when he is switched into play-back mode. |
WI

425
| Example Your Mother Doesn't Work Here Your hard-working mother uses a list as a stack: urgent tasks are added to the end of the list, interrupting longer-term plans. |
WI

Traveling Characters

78
| Example Mistress of Animals A person who moves randomly between rooms of the map. |
WI

263
| Example Odyssey A person who follows a path predetermined and stored in a table, and who can be delayed if the player tries to interact with her. |
WI

185
| Example Latris Theon A person who can accept instructions to go to new destinations and move towards them according to the most reasonable path. |
WI

291
| Example Actaeon A FOLLOW command allowing the player to pursue a person who has just left the room. |
WI

37
| Example Van Helsing A character who approaches the player, then follows him from room to room. |
WI

396
| Example Patient Zero People who wander around the map performing various errands, and in the process spread a disease which only the player can eradicate. |
WI

Obedient Characters

187
| Example The Hypnotist of Blois A hypnotist who can make people obedient and then set them free again. |
WI

239
| Example For Demonstration Purposes A character who learns new actions by watching the player performing them. |
WI

188
| Example Generation X A person who goes along with the player's instructions, but reluctantly, and will get annoyed after too many repetitions of the same kind of unsuccessful command. |
WI

184
| Example Virtue Defining certain kinds of behavior as inappropriate, so that other characters will refuse indignantly to do any such thing. |
WI

205
| Example Under Contract Creating a person who accepts most instructions and reacts correctly when a request leads implicitly to inappropriate behavior. |
WI

357
| Example Latin Lessons Supplying missing nouns and second nouns for other characters besides the player. |
WI

412
| Example Northstar Making Inform understand ASK JOSH TO TAKE INVENTORY as JOSH, TAKE INVENTORY. This requires us to use a regular expression on the player's command, replacing some of the content. |
WI

Goal-Seeking Characters

203
| Example The Man of Steel An escaping action which means "go to any room you can reach from here", and is only useful to non-player characters. |
WI

208
| Example Reporting rules for other characters' behavior Elaborating the report rules to be more interesting than "Clark goes west." |
WI

189
| Example IQ Test Introducing Ogg, a person who will unlock and open a container when the player tells him to get something inside. |
WI

190
| Example Boston Cream A fuller implementation of Ogg, giving him a motivation of his own and allowing him to react to the situation created by the player. |
WI

Social Groups

176
| Example Strictly Ballroom People who select partners for dance lessons each turn. |
WI

342
| Example Happy Hour Listing visible characters as a group, then giving some followup details in the same paragraph about specific ones. |
WI

229
| Example Unthinkable Alliances People are to be grouped into alliances. To kiss someone is to join his or her faction, which may make a grand alliance; to strike them is to give notice of quitting, and to become a lone wolf. |
WI

232
| Example The Abolition of Love A thorough exploration of all the kinds of relations established so far, with the syntax to set and unset them. |
WI

339
| Example Emma Social dynamics in which groups of people form and circulate during a party. |
WI

426
| Example Lugubrious Pete's Delicatessen In this evocation of supermarket deli counter life, a list is used as a queue to keep track of who is waiting to be served. |
WI

Bicycles, Cars and Boats

47
| Example Straw Boater Using text properties that apply only to some things and are not defined for others. |
WI

104
| Example No Relation A car which must be turned on before it can be driven, and can only go to roads. |
WI

26
| Example Peugeot A journey from one room to another that requires the player to be on a vehicle. |
WI

28
| Example Hover Letting the player see a modified room description when he's viewing the place from inside a vehicle. |
WI

Ships, Trains and Elevators

8
| Example The Unbuttoned Elevator Affair A simple elevator connecting two floors which is operated simply by walking in and out, and has no buttons or fancy doors. |
WI

260
| Example Dubai An elevator which connects any of 27 floors in a luxury hotel. |
WI

40
| Example Fore Understand "fore", "aft", "port", and "starboard", but only when the player is on a vessel. |
WI

145
| Example Empire A train which follows a schedule, stopping at a number of different locations. |
WI

Animals

386
| Example Feline Behavior A cat which reacts to whatever items it has handy, returning the result of a rulebook for further processing. |
WI

99
| Example Today Tomorrow A few notes on "In the presence of" and how it interacts with concealed objects. |
WI

410
| Example Fido A dog the player can name and un-name at will. |
WI

Furniture

83
| Example Yolk of Gold Set of drawers where the item the player seeks is always in the last drawer he opens, regardless of the order of opening. |
WI

172
| Example Princess and the Pea The player is unable to sleep on a mattress (or stack of mattresses) because the bottom one has something uncomfortable under it. |
WI

57
| Example U-Stor-It A "chest" kind which consists of a container which has a lid as a supporter. |
WI

393
| Example Swigmore U. Adding a new kind of supporter called a perch, where everything dropped lands on the floor. |
WI

347
| Example Kiwi Creating a raised supporter kind whose contents the player can't see or take from the ground. |
WI

12
| Example Tamed Examples of a container and a supporter that can be entered, as well as nested rooms. |
WI

423
| Example Circle of Misery Retrieving items from an airport luggage carousel is such fun, how can we resist simulating it, using a list as a ring buffer? |
WI

Kitchen and Bathroom

438
| Example Modern Conveniences Exemplifying the kind of source we might use in writing extensions for kitchen and bathroom appliances. |
WI

75
| Example Versailles A mirror which will reflect some random object in the room. |
WI

Food

365
| Example Lollipop Guild Overriding the rules to allow the player to eat something without first taking it. |
WI

197
| Example Delicious, Delicious Rocks Adding a "sanity-check" stage to decide whether an action makes any sense, which occurs before any before rules, implicit taking, or check rules. |
WI

46
| Example Would you...? Adding new properties to objects, and checking for their presence. |
WI

376
| Example Stone A soup to which the player can add ingredients, which will have different effects when the player eats. |
WI

133
| Example Candy One of several identical candies chosen at the start of play to be poisonous. |
WI

143
| Example MRE Hunger that eventually kills the player, and foodstuffs that can delay the inevitable by different amounts of time. |
WI

Bags, Bottles, Boxes and Safes

287
| Example Safety A safe whose dial can be turned with SPIN SAFE TO 1131, and which will open only with the correct combination. |
WI

421
| Example Eyes, Fingers, Toes A safe with a multi-number combination, meant to be dialed over multiple turns, is implemented using a log of the last three numbers dialed. The log can then be compared to the safe's correct combination. |
WI

327
| Example Trachypachidae Maturin 1803 Bottles with removable stoppers: when the stopper is in the bottle, the bottle is functionally closed, but the stopper can also be removed and used elsewhere. Descriptions of the bottle reflect its state intelligently. |
WI

309
| Example Cinco A taco shell that can be referred to (when it contains things) in terms of its contents. |
WI

326
| Example Shipping Trunk A box of baking soda whose name changes to "completely ineffective baking soda" when it is in a container with something that smells funny. |
WI

331
| Example Unpeeled Calling an onion "a single yellow onion" when (and only when) it is being listed as the sole content of a room or container. |
WI

329

Example Hudsucker Industries
Letters which are described differently as a group, depending on whether the player has read none, some, or all of them, and on whether they are alike or unlike.

WI

59

Example Fallout Enclosure
Adding an enclosure kind that includes both containers and supporters in order to simplify text that would apply to both.

WI

Clothing

44
| Example Get Me to the Church on Time Using kinds of clothing to prevent the player from wearing several pairs of trousers at the same time. |
WI

234

Example Bogart
Clothing for the player that layers, so that items cannot be taken off in the wrong order, and the player's inventory lists only the clothing that is currently visible.

WI

241

Example What Not To Wear
A general-purpose clothing system that handles a variety of different clothing items layered in different combinations over different areas of the body.

WI

325

Example Hays Code
Clark Gable in a pin-striped suit and a pink thong.

WI

54

Example Being Prepared
A kind for jackets, which always includes a container called a pocket.

WI

319

Example Some Assembly Required
Building different styles of shirt from component sleeves and collars.

WI

Money

253
| Example Frozen Assets A treatment of money which keeps track of how much the player has on him, and a BUY command which lets him go shopping. |
WI

272

Example Introduction to Juggling
Assortment of equipment defined with price and description, in a table.

WI

254

Example Money for Nothing
An OFFER price FOR command, allowing the player to bargain with a flexible seller.

WI

251

Example Nickel and Dimed
A more intricate system of money, this time keeping track of the individual denominations of coins and bills, specifying what gets spent at each transaction, and calculating appropriate change.

WI

258

Example Fabrication
A system of assembling clothing from a pattern and materials; both the pattern and the different fabrics have associated prices.

WI

252

Example Widget Enterprises
Allowing the player to set a price for a widget on sale, then determining the resulting sales based on consumer demand, and the resulting profit and loss.

WI

Dice and Playing Cards

264
| Example Jokers Wild A deck of cards which can be shuffled and dealt from. |
WI

306

Example Tilt 1
A deck of cards with fully implemented individual cards, which can be separately drawn and discarded, and referred to by name.

WI

389

Example Tilt 2
A deck of cards with fully implemented individual cards; when the player has a full poker hand, the inventory listing describes the resulting hand accordingly.

WI

175

Example Wonka's Revenge
A lottery drum which redistributes the tickets inside whenever the player spins it.

WI

129

Example Do Pass Go
A pair of dice which can be rolled, and are described with their current total when not carried, and have individual scores when examined.

WI

Reading Matter

94
| Example Costa Rican Ornithology A fully-implemented book, answering questions from a table of data, and responding to failed consultation with a custom message such as "You flip through the Guide to Central American Birds, but find no reference to penguins." |
WI

292

Example Pages
A book with pages that can be read by number (as in "read page 3 in...") and which accepts relative page references as well (such as "read the last page of...", "read the next page", and so on).

WI

313

Example Bibliophilia
A bookshelf with a number of books, where the player's command to examine something will be interpreted as an attempt to look up titles if the bookshelf is present, but otherwise given the usual response.

WI

322

Example AARP-Gnosis
An Encyclopedia set which treats volumes in the same place as a single object, but can also be split up.

WI

281

Example The Trouble with Printing
Making a READ command, distinct from EXAMINE, for legible objects.

WI

432

Example The Fourth Body
Notebooks in which the player can record assorted notes throughout play.

WI

433

Example The Fifth Body
An expansion on the notebook, allowing the player somewhat more room in which to type his recorded remark.

WI

Painting and Labeling Devices

297
| Example Palette An artist's workshop in which the canvas can be painted in any colour, and where painterly names for pigments ("cerulean") are accepted alongside everyday ones ("blue"). |
WI

53

Example Early Childhood
A child's set of building blocks, which come in three different colours - red, green and blue - but which can be repainted during play.

WI

34

Example Brown
A red sticky label which can be attached to anything in the game, or removed again.

WI

Simple Machines

61
| Example Control Center Objects which automatically include a description of their component parts whenever they are examined. |
WI

55

Example Model Shop
An "on/off button" which controls whatever device it is part of.

WI

50

Example Signs and Portents
Signpost that points to various destinations, depending on how the player has turned it.

WI

416

Example What Makes You Tick
Building a fishing pole from several component parts that the player might put together in any order.

WI

Televisions and Radios

324
| Example Aftershock Modifying the rules for examining a device so that all devices have some specific behavior when switched on, which is described at various times. |
WI

66

Example Radio Daze
A radio that produces a cycle of output using varying text.

WI

300

Example Aspect
Understanding aspect ratios (a unit) in the names of televisions.

WI

304

Example Channel 1
Understanding channels (a number) in the names of televisions.

WI

305

Example Channel 2
Understanding channels (a number) in the names of televisions, with more sophisticated parsing of the change channel action.

WI

Telephones

226
| Example Four Cheeses A system of telephones on which the player can call distant persons and have conversations. |
WI

Clocks and Scientific Instruments

288
| Example Tom's Midnight Garden A clock kind that can be set to any time using "the time understood"; may be turned on and off; and will advance itself only when running. Time on the face is also reported differently depending on whether the clock is analog or digital. |
WI

351

Example Ginger Beer
A portable magic telescope which allows the player to view items in another room of his choice.

WI

180

Example Witnessed 2
A piece of ghost-hunting equipment that responds depending on whether or not the meter is on and a ghost is visible or touchable from the current location.

WI

Cameras and Recording Devices

262
| Example If It Hadn't Been For... A sound recording device that records the noises made by player and non-player actions, then plays them back on demand. |
WI

311

Example Claims Adjustment
An instant camera that spits out photographs of anything the player chooses to take a picture of.

WI

354

Example Originals
Allowing the player to create models of anything in the game world; parsing the name "model [thing]" or even just "[thing]" to refer to these newly-created models; asking "which do you mean, the model [thing] or the actual [thing]" when there is ambiguity.

WI

406

Example Mirror, Mirror
The sorcerer's mirror can, when held up high, form an impression of its surroundings which it then preserves.

WI

221

Example Actor's Studio
A video camera that records actions performed in its presence, and plays them back with time-stamps.

WI

Gases

74
| Example Only You... Smoke which spreads through the rooms of the map, but only every other turn. |
WI

394

Example Lethal Concentration 1
A poisonous gas that spreads from room to room, incapacitating or killing the player when it reaches sufficient levels.

WI

395

Example Lethal Concentration 2
Poisonous gas again, only this time it sinks.

WI

Liquids

122
| Example Beverage Service A potion that the player can drink. |
WI

193

Example 3 AM
A shake command which agitates soda and makes items thump around in boxes.

WI

192

Example Frizz
Liquid flows within containers and soaks objects that are not waterproof; any contact with a wet object can dampen our gloves.

WI

385

Example Flotation
Objects that can sink or float in a well, depending on their own properties and the state of the surrounding environment.

WI

277

Example Xylan
Creating a new command that does require an object to be named; and some comments about the choice of vocabulary, in general.

WI

118

Example Thirst
A waterskin that is depleted as the player drinks from it.

WI

255

Example Lemonade
Containers for liquid which keep track of how much liquid they are holding and of what kind, and allow quantities to be moved from one container to another.

WI

256

Example Savannah
Using the liquid implementation demonstrated in Lemonade for putting out fires.

WI

265

Example Noisy Cricket
Implementing liquids that can be mixed, and the components automatically recognized as matching one recipe or another.

WI

320

Example Lakeside Living
Similar to "Lemonade", but with bodies of liquid that can never be depleted, and some adjustments to the "fill" command so that it will automatically attempt to fill from a large liquid source if possible.

WI

Dispensers and Supplies of Small Objects

124
| Example Extra Supplies A supply of red pens from which the player can take another pen only if he doesn't already have one somewhere in the game world. |
WI

364

Example Pizza Prince
Providing a pizza buffet from which the player can take as many pieces as he wants.

WI

Glass and Other Damage-Prone Substances

97
| Example Ming Vase ATTACK or DROP break and remove fragile items from play. |
WI

123

Example Spring Cleaning
A character who sulks over objects that the player has broken (and which are now off-stage).

WI

387

Example Kyoto
Expanding the effects of the THROW something AT something command so that objects do make contact with one another.

WI

302

Example Terracottissima
The flowerpots once again, but this time arranged so that after the first breakage all undamaged pots are said to be "unbroken", to distinguish them from the others.

WI

195

Example Paddington
A CUT [something] WITH [something] command which acts differently on different types of objects.

WI

Volume, Height, Weight

247
| Example Dimensions This example draws together the previous snippets into a working implementation of the weighbridge. |
WI

259

Example The Speed of Thought
Describing scientifically-measured objects in units more familiar to the casual audience.

WI

257

Example Depth
Receptacles that calculate internal volume and the amount of room available, and cannot be overfilled.

WI

248

Example Lead Cuts Paper
To give every container a breaking strain, that is, a maximum weight of contents which it can bear - so that to put the lead pig into a paper bag invites disaster.

WI

231

Example Swerve left? Swerve right? Or think about it and die?
Building a marble chute track in which a dropped marble will automatically roll downhill.

WI

Ropes

250
| Example Snip A string which can be cut into arbitrary lengths, and then tied back together. |
WI

228

Example Otranto
A kind of rope which can be tied to objects and used to anchor the player or drag items from room to room.

WI

Electricity and Magnetism

139
| Example Witnessed 1 A kind of battery which can be put into different devices, and which will lose power after extended use. |
WI

398

Example Electrified
Adding a rule before the basic accessibility rule that will prevent the player from touching electrified objects under the wrong circumstances.

WI

332

Example Rules of Attraction
A magnet which picks up nearby metal objects, and describes itself appropriately in room descriptions and inventory listings, but otherwise goes by its ordinary name.

WI

Fire

151
| Example Bruneseau's Journey A candle which reacts to lighting and blowing actions differently depending on whether it has already been lit once. |
WI

117

Example Thirst 2
A campfire added to the camp site, which can be lit using tinder.

WI

407

Example The Cow Exonerated
Creating a class of matches that burn for a time and then go out, with elegant reporting when several matches go out at once.

WI

384

Example In Fire or in Flood
A BURN command; flammable objects which light other items in their vicinity and can burn for different periods of time; the possibility of having parts or contents of a flaming item which survive being burnt.

WI

Heat

85
| Example Grilling A grill, from which the player is not allowed to take anything lest he burn himself. |
WI

315

Example Masochism Deli
Multiple potatoes, with rules to make the player drop the hot potato first and pick it up last.

WI

318

Example Hot Glass Looks Like Cold Glass
Responding to references to a property that the player isn't yet allowed to mention (or when not to use "understand as a mistake").

WI

182

Example Entropy
All objects in the game have a heat, but if not kept insulated they will tend toward room temperature (and at a somewhat exaggerated rate).

WI

Magic (Breaking the Laws of Physics)

227
| Example Transmutations A machine that turns objects into other, similar objects. |
WI

216

Example Magneto's Revenge
Kitty Pryde of the X-Men is able to reach through solid objects, so we might implement her with special powers that the player does not have...

WI

390

Example Access All Areas
The Pointy Hat of Liminal Transgression allows its wearer to walk clean through closed doors.

WI

224

Example Interrogation
A wand which, when waved, reveals the concealed items carried by people the player can see.

WI

Mathematics

424
| Example The Fibonacci Sequence The modest Leonardo Fibonacci of Pisa will be only too happy to construct his sequence on request, using an array. |
WI

427

Example Sieve of Eratosthenes
The haughty Eratosthenes of Cyrene will nevertheless consent to sieve prime numbers on request.

WI

240

Example Number Study
The parity and joint magnitude relations explored.

WI

Start-Up Features

368
| Example Bikini Atoll Delaying the banner for later. |
WI

429

Example Alien Invasion Part 23
Keeping a preference file that could be loaded by any game in a series.

WI

126

Example Hatless
It's tempting to use "now..." to distribute items randomly at the start of play, but we need to be a little cautious about how we do that.

WI

Saving and Undoing

211
| Example A point for never saving the game In some of the late 1970s "cave crawl" adventure games, an elaborate scoring system might still leave the player perplexed as to why an apparently perfect play-through resulted in a score which was still one point short of the supposed maximum. Why only 349 out of 350? The answer varied, but sometimes the last point was earned by never saving the game - in other words by playing it right through with nothing to guard against mistakes (except perhaps UNDO for the last command), and in one long session. |
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210

Example Spellbreaker
P. David Lebling's classic "Spellbreaker" (1986) includes a room where the game cannot be saved: here is an Inform implementation.

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Helping and Hinting

111
| Example Y ask Y? Noticing when the player seems to be at a loss, and recommending the use of hints. |
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392

Example Solitude
Novice mode that prefaces every prompt with a list of possible commands the player could try, and highlights every important word used, to alert players to interactive items in the scenery.

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317

Example Query
Catching all questions that begin with WHO, WHAT, WHERE, and similar question words, and responding with the instruction to use commands, instead.

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52

Example Real Adventurers Need No Help
Allowing the player to turn off all access to hints for the duration of a game, in order to avoid the temptation to rely on them overmuch.

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273

Example Food Network Interactive
Using a menu system from an extension, but adding our own material to it for this game.

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285

Example Ish.
A (very) simple HELP command, using tokens to accept and interpret the player's text whatever it might be.

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274

Example Trieste
Table amendment to adjust HELP commands provided for the player.

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230

Example The Unexamined Life
An adaptive hint system that tracks what the player needs to have seen or to possess in order to solve a given puzzle, and doles out suggestions accordingly. Handles changes in the game state with remarkable flexibility, and allows the player to decide how explicit a nudge he wants at any given moment.

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Scoring

137
| Example No Place Like Home Recording a whole table of scores for specific treasures. |
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219

Example Bosch
Creating a list of actions that will earn the player points, and using this both to change the score and to give FULL SCORE reports.

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136

Example Mutt's Adventure
Awarding points for visiting a room for the first time.

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269

Example Goat-Cheese and Sage Chicken
Implementing a FULL SCORE command which lists more information than the regular SCORE command, adding times and rankings, as an extension of the example given in this chapter.

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166

Example Panache
Replacing the score with a plot summary that records the events of the plot, scene by scene.

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431

Example Rubies
A scoreboard that keeps track of the ten highest-scoring players from one playthrough to the next, adding the player's name if he has done well enough.

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Ending The Story

370
| Example Battle of Ridgefield Completely replacing the endgame text and stopping the game without giving the player a chance to restart or restore. |
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369

Example Finality
Not mentioning UNDO in the final set of options.

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372

Example Xerxes
Offering the player a menu of things to read after winning the game.

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371

Example Jamaica 1688
Adding a feature to the final question after victory, so that the player can choose to reveal notes about items in the game.

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430

Example Labyrinth of Ghosts
Remembering the fates of all previous explorers of the labyrinth.

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138

Example Big Sky Country
Allowing the player to continue play after a fatal accident, but penalizing him by scattering his possessions around the game map.

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Typography

443
| Example Chanel Version 1 Making paired italic and boldface tags like those used by HTML for web pages. |
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70

Example The Über-complète clavier
This example provides a fairly stringent test of exotic lettering.

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69

Example Garibaldi 2
Adding coloured text to the example of door-status readouts.

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439

Example Tilt 3
Displaying the card suits from our deck of cards with red and black colored unicode symbols.

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The Status Line

373
| Example Blankness Emptying the status line during the first screen of the game. |
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402

Example Capital City
To arrange that the location information normally given on the left-hand side of the status line appears in block capitals.

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115

Example Centered
Replacing the two-part status line with one that centers only the room name at the top of the screen.

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442

Example Status line with centered text, the hard way
A status line which has only the name of the location, centered.

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336

Example Ways Out
A status line that lists the available exits from the current location.

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337

Example Guided Tour
A status line that lists the available exits from the current location, changing the names of these exits depending on whether the room has been visited or not.

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114

Example Politics as Usual
Have the status line indicate the current region of the map.

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Footnotes

289
| Example Ibid. A system which allows the author to assign footnotes to descriptions, and permits the player to retrieve them again by number, using "the number understood". Footnotes will automatically number themselves, according to the order in which the player discovers them. |
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Glulx Multimedia Effects

434
| Example Flathead News Network Using external files, together with a simple Unix script running in the background, to provide live news headlines inside a story file. |
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Testing

58
| Example Bic Testing to make sure that all objects have been given descriptions. |
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404

Example Alpha
Creating a beta-testing command that matches any line starting with punctuation.

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Publishing

436
| Example Baedeker Creating a floorplan of the cathedral using the locations from previous examples. |
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437

Example Bay Leaves and Honey Wine
Creating a map of Greece using the locations from previous examples.

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435

Example Port Royal 5
Port Royal scenario given instructions for an EPS map.

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