The built-in activities and their default stock of rules; and in particular, the locale description mechanism.


§1. These must not be created until the basic rulebooks are in place, because creating any activity automatically creates three rulebooks as well.

The srules template expects the following activities to be created and in this order. (That is, the order here must exactly match that of the *_ACT constant definitions made in Definitions.i6t.) The activities are fairly completely described in the Inform documentation, so the only notes here concern implementation.

Part Four - Activities

§2. Issuing responses. Responses are textual replies made by rules, and while one could imagine uses for them outside of an IF-like dialogue, they belong better in the Standard Rules (i.e., as an aspect of IF) than in the general-purpose language. So STANDARD_RESPONSE_ISSUING_R is in srules, not basicinform, and we define:

Section 1 - Responses

Issuing the response text of something -- hidden in RULES command -- -- documented at act_resp -- is an
activity on responses.
The issuing the response text activity is accessible to Inter as "PRINTING_RESPONSE_ACT".

The standard issuing the response text rule is listed last in for issuing the
response text.

The standard issuing the response text rule is defined by Inter as
"STANDARD_RESPONSE_ISSUING_R".

§3. Naming and listing. We start with a piece of unfinished business. The "printing the name" activity was created by Basic Inform, but we need to add a rule to its before rule which marks any item whose name is being printed with the "mentioned" property, for reasons to be found below.

Section 2 - Naming and Listing

Before printing the name of a thing (called the item being printed)
    (this is the make named things mentioned rule):
    if expanding text for comparison purposes, continue the activity;
    now the item being printed is mentioned.

Printing a number of something (documented at act_pan) is an activity.
The printing a number activity is accessible to Inter as "PRINTING_A_NUMBER_OF_ACT".

Rule for printing a number of something (called the item) (this is the standard
    printing a number of something rule):
    say "[listing group size in words] ";
    carry out the printing the plural name activity with the item.
The standard printing a number of something rule is listed last in the for printing
a number rulebook.

§4. When they occur in room descriptions, names of things are sometimes supplemented by details:

Printing room description details of something (hidden in RULES command) (documented at act_details) is an activity.
The printing room description details activity is accessible to Inter as "PRINTING_ROOM_DESC_DETAILS_ACT".

For printing room description details of a container (called the box) when the box is falsely-unoccupied (this is the falsely-unoccupied container room description details rule):
  say text of list writer internal rule response (A); " ("
  if the box is lit and the location is unlit begin;
    if the box is closed, say text of list writer internal rule response (J); [ "closed, empty[if serial comma option is active],[end if] and providing light" ]
    else say text of list writer internal rule response (I); "empty and providing light"
  else;
    if the box is closed, say text of list writer internal rule response (E); "closed"
    else say text of list writer internal rule response (F); "empty"
  end if;
  say text of list writer internal rule response (B); ")"

Printing inventory details of something (hidden in RULES command) (documented at act_idetails) is an activity.
The printing inventory details activity is accessible to Inter as "PRINTING_INVENTORY_DETAILS_ACT".


To say the deceitfully empty inventory details of (box - a container):
  let inventory text printed be false;
  if the box is lit begin;
    if the box is worn, say text of list writer internal rule response (K); "providing light and being worn"
    else say text of list writer internal rule response (D); "providing light"
    now inventory text printed is true;
  else if the box is worn;
    say text of list writer internal rule response (L); "being worn"
    now inventory text printed is true;
  end if;
  if the box is openable begin;
    if inventory text printed is true begin;
      if the serial comma option is active, say ",";
      say text of list writer internal rule response (C); "and"
    end if;
    if the box is open begin;
      say text of list writer internal rule response (N); "open but empty"
    else; it's closed
      if the box is locked, say text of list writer internal rule response (P); "closed and locked"
      else say text of list writer internal rule response (O); "closed"
      now inventory text printed is true;
    end if;
  else; it's not openable
    if the box is transparent begin;
      if inventory text printed is true, say text of list writer internal rule response (C); "and"
      say text of list writer internal rule response (F); "empty"
      now inventory text printed is true; not relevant unless code is added
    end if;
  end if;

For printing inventory details of a container (called the box) when the box is falsely-unoccupied (this is the falsely-unoccupied container inventory details rule):
    let the tag be "[the deceitfully empty inventory details of box]";
    if tag is not empty begin;
      say text of list writer internal rule response (A); "("
      say tag;
      say text of list writer internal rule response (B); ")"
    end if;

§5. Names of things are often formed up into lists, in which they are sometimes grouped together:

Listing contents of something (hidden in RULES command) (documented at act_lc) is an activity.
The listing contents activity is accessible to Inter as "LISTING_CONTENTS_ACT".
The standard contents listing rule is listed last in the for listing contents rulebook.
The standard contents listing rule is defined by Inter as "STANDARD_CONTENTS_LISTING_R".
Grouping together something (hidden in RULES command) (documented at act_gt) is an activity.
The grouping together activity is accessible to Inter as "GROUPING_TOGETHER_ACT".

§6. And such lists of names are formed up in turn into room descriptions. Something which is visible in a room can either have a paragraph of its own or can be relegated to the list of "nondescript" items at the end.

Writing a paragraph about something (documented at act_wpa) is an activity.
The writing a paragraph about activity is accessible to Inter as "WRITING_A_PARAGRAPH_ABOUT_ACT".

§7. When these paragraphs have all gone by, the nondescript items left over are more briefly listed: the following activity gets the chance to change how this is done.

Listing nondescript items of something (documented at act_lni) is an activity.
The listing nondescript items activity is accessible to Inter as "LISTING_NONDESCRIPT_ITEMS_ACT".

§8. Darkness behaves, for room description purposes, a little as if it were a room in its own right. Until the 1990s that was almost always how darkness was implemented in IF programs: this persists in I6, but not I7, where the existence of a room-which-is-not-a-room would break type safety.

Printing the name of a dark room (documented at act_darkname) is an activity.
The printing the name of a dark room activity is accessible to Inter as "PRINTING_NAME_OF_DARK_ROOM_ACT".
Printing the description of a dark room (documented at act_darkdesc) is an activity.
The printing the description of a dark room activity is accessible to Inter as "PRINTING_DESC_OF_DARK_ROOM_ACT".
Printing the announcement of darkness (documented at act_nowdark) is an activity.
The printing the announcement of darkness activity is accessible to Inter as "PRINTING_NEWS_OF_DARKNESS_ACT".
Printing the announcement of light (documented at act_nowlight) is an activity.
The printing the announcement of light activity is accessible to Inter as "PRINTING_NEWS_OF_LIGHT_ACT".
Printing a refusal to act in the dark (documented at act_toodark) is an activity.
The printing a refusal to act in the dark activity is accessible to Inter as "REFUSAL_TO_ACT_IN_DARK_ACT".

The look around once light available rule is listed last in for printing the
announcement of light.

This is the look around once light available rule:
    try looking.

§9. Two special forms of printing: the status line at the top of the screen, refreshed every turn during play, and the banner which appears at or close to the start of play:

Constructing the status line (documented at act_csl) is an activity.
The constructing the status line activity is accessible to Inter as "CONSTRUCTING_STATUS_LINE_ACT".
Printing the banner text (documented at act_banner) is an activity.
The printing the banner text activity is accessible to Inter as "PRINTING_BANNER_TEXT_ACT".

§10. Parsing activites. Now a brace of activities to intervene in how the command parser does its parsing, arranged roughly in chronological order of their typical use during a single turn of a typed command, its parsing, and final conversion into an action.

The unusual notation "(future action)" here allows Inform to parse rule preambles for these activities in a way which would refer to the action which might, at some point in the future, be generated — during parsing we don't of course yet know what that action is, but there is always a current guess at what it might be.

Section 3 - Command parsing

Reading a command (documented at act_reading) is an activity.
The reading a command activity is accessible to Inter as "READING_A_COMMAND_ACT".
Deciding the scope of something (future action) (documented at act_ds) is an activity.
The deciding the scope activity is accessible to Inter as "DECIDING_SCOPE_ACT".
Deciding the concealed possessions of something (documented at act_con) is an activity.
The deciding the concealed possessions activity is accessible to Inter as "DECIDING_CONCEALED_POSSESS_ACT".
Deciding whether all includes something (future action) (documented at act_all)
    is an activity.
The deciding whether all includes activity is accessible to Inter as "DECIDING_WHETHER_ALL_INC_ACT".
The for deciding whether all includes rules have outcomes it does not (failure) and
    it does (success).
Clarifying the parser's choice of something (future action) (documented at act_clarify)
    is an activity.
The clarifying the parser's choice activity is accessible to Inter as "CLARIFYING_PARSERS_CHOICE_ACT".
Asking which do you mean (future action) (documented at act_which) is an activity.
The asking which do you mean activity is accessible to Inter as "ASKING_WHICH_DO_YOU_MEAN_ACT".
Printing a parser error (documented at act_parsererror) is an activity.
The printing a parser error activity is accessible to Inter as "PRINTING_A_PARSER_ERROR_ACT".
Supplying a missing noun (documented at act_smn) is an activity.
The supplying a missing noun activity is accessible to Inter as "SUPPLYING_A_MISSING_NOUN_ACT".
Supplying a missing second noun (documented at act_smn) is an activity.
The supplying a missing second noun activity is accessible to Inter as "SUPPLYING_A_MISSING_SECOND_ACT".
Implicitly taking something (documented at act_implicitly) is an activity.
The implicitly taking activity is accessible to Inter as "IMPLICITLY_TAKING_ACT".

§11. Here are the default rules for the behaviour of ALL:

Rule for deciding whether all includes scenery while an actor taking or taking off or
    removing (this is the exclude scenery from take all rule): it does not.
Rule for deciding whether all includes people while an actor taking or taking off or
    removing (this is the exclude people from take all rule): it does not.
Rule for deciding whether all includes fixed in place things while an actor taking or
    taking off or removing (this is the exclude fixed in place things from
    take all rule): it does not.
Rule for deciding whether all includes things enclosed by the person reaching
    while an actor taking or taking off (this is the exclude indirect possessions from
    take all rule): it does not.
Rule for deciding whether all includes a person while an actor dropping or throwing
    or inserting or putting (this is the exclude people from drop all rule):
    it does not.

§12. The supplying activities are linguistically interesting, for reasons gone into in the paper "Interactive Fiction, Natural Language and Semantic Analysis": English verbs do not naturally seem to feature optional nouns. Indeed, we say "it rained on Tuesday" where "it" refers to nothing at all, merely because we can't bring ourselves to leave a gap and say just "rained on Tuesday". A better example here would be "it sounded like rain", because we do the same to convey the idea of listening ambiently rather than to any single thing: listening appears to be rare among actions in that it can equally well take a noun as not. Just as English handles this problem by supplying a spurious "it" which appears to mean "the world at large", so Inform handles it by supplying the current location, with the same idea in mind. And the same applies to the sense of smell, which can be similarly defocused.

Rule for supplying a missing noun while an actor smelling (this is the ambient odour rule):
    now the noun is the touchability ceiling of the player.

Rule for supplying a missing noun while an actor listening (this is the ambient sound rule):
    now the noun is the touchability ceiling of the player.

§13. The following rule is something of a dodge to provide a better parser response to commands like GO or BRETT, GO. (Putting the rule here, and giving it a name, allows the user to override it and thus accept the idea of vague going after all.)

Rule for supplying a missing noun while an actor going (this is the block vaguely going rule):
    say "You'll have to say which compass direction to go in." (A).

§14. Implicit taking is delegated to the I6 template:

The standard implicit taking rule is listed last in for implicitly taking.

The standard implicit taking rule is defined by Inter as "STANDARD_IMPLICIT_TAKING_R" with
    "(first taking [the noun])[command clarification break]" (A),
    "([the second noun] first taking [the noun])[command clarification break]" (B).

§15. Posthumous activities. The very last rules of all. The obituary is a rare example of a sequence of events in the I6 library having been rolled up into an activity, partly because it's one of the few clear-cut moments where several unconnected things happen in succession.

Section 4 - Posthumous activities

Amusing a victorious player (documented at act_amuse) is an activity.
The amusing a victorious player activity is accessible to Inter as "AMUSING_A_VICTORIOUS_PLAYER_ACT".

Printing the player's obituary (documented at act_obit) is an activity.
The printing the player's obituary activity is accessible to Inter as "PRINTING_PLAYERS_OBITUARY_ACT".
The print obituary headline rule is listed last in for printing the player's obituary.
The print final score rule is listed last in for printing the player's obituary.
The display final status line rule is listed last in for printing the player's obituary.

The print obituary headline rule is defined by Inter as "PRINT_OBITUARY_HEADLINE_R"
    with " You have died " (A),
        " You have won " (B),
        " The End " (C).
The print final score rule is defined by Inter as "PRINT_FINAL_SCORE_R".
The display final status line rule is defined by Inter as "DISPLAY_FINAL_STATUS_LINE_R".

§16. There is one last question: the one which usually reads "Would you like to RESTART, RESTORE a saved game, or QUIT?", but which sometimes provides other options too. The "ask the final question rule" handles this, and does so by repeatedly calling the following activity:

Handling the final question is an activity.
The handling the final question activity is accessible to Inter as "DEALING_WITH_FINAL_QUESTION_ACT".

§17. It follows that this activity must at least sometimes do something dramatic to the execution state: perform a quit, for instance. Four primitive rules are available for the drastic things which the activity might wish to do, but these are not placed in any rulebook: instead they are available for anyone who wants to call them. (In the default implementation below, we put references to them into a table.)

The immediately restart the VM rule is defined by Inter as "IMMEDIATELY_RESTART_VM_R".
The immediately restore saved game rule is defined by Inter as "IMMEDIATELY_RESTORE_SAVED_R".
The immediately quit rule is defined by Inter as "IMMEDIATELY_QUIT_R".
The immediately undo rule is defined by Inter as "IMMEDIATELY_UNDO_R" with
    "The use of 'undo' is forbidden in this story." (A),
    "You can't 'undo' what hasn't been done!" (B),
    "Your interpreter does not provide 'undo'. Sorry!" (C),
    "'Undo' failed. Sorry!" (D),
    "[bracket]Previous turn undone.[close bracket]" (E),
    "'Undo' capacity exhausted. Sorry!" (F).

§18. We structure the activity so that the printing of the question and typing of the answer take place at the "before" stage, and then the parsing and acting upon this answer take place at the "for" stage. Reading the keyboard is the last rule in "before". With the "for" stage, the idea is that any extra rule slipped in by the user can take precedence over the default implementation, so the latter is the last there, too.

The print the final question rule is listed in before handling the final question.
The print the final prompt rule is listed in before handling the final question.
The read the final answer rule is listed last in before handling the final question.
The standard respond to final question rule is listed last in for handling the final question.

This is the print the final prompt rule: say "> [run paragraph on]" (A).

The read the final answer rule is defined by Inter as "READ_FINAL_ANSWER_R".

§19. That clears away the underbrush and reduces us to two matching tasks: (i) to print the question, (ii) to parse the answer, given that we want to be able to vary the set of choices available.

We do this by reading the options from the Table of Final Question Options. (See below for its default contents.) Each row is an option, whose wording must be placed in the topic column. The final question wording entry can either be text describing the option — e.g., "perform a RESTART" — or can be left blank, making the option a secret one, omitted from the question but still recognised as an answer. The only if victorious entry can be set to make the option available only after a victorious ending, not after a loss; Infocom's traditional AMUSING option behaved thus. Finally, the table specifies what to do if the option is taken: either it provides a rule, or an activity to carry out. (If it provides only an activity, but that activity is empty, then the option is omitted from the question and not recognised as an answer.)

Section 5 - The Final Question

This is the print the final question rule:
    let named options count be 0;
    repeat through the Table of Final Question Options:
        if the only if victorious entry is false or the story has ended finally:
            if there is a final response rule entry
                or the final response activity entry is not empty:
                if there is a final question wording entry, increase named options count by 1;
    if the named options count is less than 1, abide by the immediately quit rule;
    say "Would you like to " (A);
    repeat through the Table of Final Question Options:
        if the only if victorious entry is false or the story has ended finally:
            if there is a final response rule entry
                or the final response activity entry is not empty:
                if there is a final question wording entry:
                    say final question wording entry;
                    decrease named options count by 1;
                    if the named options count is 1:
                        if the serial comma option is active, say ",";
                        say " or " (B);
                    otherwise if the named options count is 0:
                        say "?[line break]";
                    otherwise:
                        say ", ";

§20. And the matching rule to parse and respond to the answer:

This is the standard respond to final question rule:
    repeat through the Table of Final Question Options:
        if the only if victorious entry is false or the story has ended finally:
            if there is a final response rule entry
                or the final response activity entry is not empty:
                if the player's command matches the topic entry:
                    if there is a final response rule entry, abide by final response rule entry;
                    otherwise carry out the final response activity entry activity;
                    rule succeeds;
    say "Please give one of the answers above." (A).

§21. The table of final options is the only material under the following heading to make it easier for users to replace with entirely different tables.

These settings are the traditional ones used by Inform since 1995 or so. The UNDO option has customarily been a "secret", though not much of one, since it somewhat cheapens the announcement of a calamity to be immediately offered the chance to reverse it: death, where is thy sting?

Section 6 - Final question options

Table of Final Question Options
final question wording  only if victorious  topic       final response rule     final response activity
"RESTART"               false               "restart"   immediately restart the VM rule --
"RESTORE a saved game"  false               "restore"   immediately restore saved game rule --
"see some suggestions for AMUSING things to do" true    "amusing"   --  amusing a victorious player
"QUIT"                  false               "quit"      immediately quit rule   --
"UNDO the last command" false               "undo"      immediately undo rule   --

§22. Locale activities. A "locale description" is a segment of the text produced by LOOK: the "locale" is a clutch of objects at a given level in the object tree. Most room descriptions consist of a top line, a description of the place, and then a single (though often, as here, multi-paragraph) locale:

    Sentier Le Corbusier
    A coastal walk along the rocky shore between Nice and Menton.
        ...now the locale for the room Sentier Le Corbusier:
    A translucent jellyfish has been washed up by the waves.

    You can also see a bucket and a spade here.

A locale typically contains a run of paragraphs specific to interesting items, especially those not yet picked up, followed by a paragraph which lists the "nondescript" items — those not given paragraphs of their own, such as the bucket and spade. (Some items, though — typically scenery, but also for instance the player — are not even nondescript and do not appear at all.) A locale can contain no interesting paragraphs, or no list of nondescript items, or can even contain neither: that is, it can be entirely empty.

When the player is in or on top of something, multiple locales are described:

    Sentier Le Corbusier (in the golf cart)
    A coastal walk along the rocky shore between Nice and Menton.
        ...now the locale for the room Sentier Le Corbusier:
    A translucent jellyfish has been washed up by the waves.

    You can also see a bucket and a spade here.
        ...now the locale for the golf cart:
    In the golf cart you can see a map of Villefranche-sur-Mer.

To sum up, the text produced by LOOK consists of a header (produced by the carry out looking rules) followed by one or more locale descriptions (produced by the activity below).

§23. Locale Implementation. When describing a locale, we keep a Table of interesting objects, each associated with a priority — a number indicating how important, and therefore how near to the top of the description, the object is. A special syntax allows us to create the Table with exactly the same number of rows as there are things in the model world: thus, in the worst case where all things are in a single locale, we still will not run out of table rows. (We do this rather than creating a large but fixed-size table because memory is very short in some Z-machine I7 works, so we want to take only what we might actually need. The table structure is not as wasteful as it might look: an experiment with using a number property of things instead showed that this table was actually more efficient, because of the property numbering overhead in the Z-machine memory representation of objects.)

Section 7 - Locale descriptions - Unindexed

Table of Locale Priorities
notable-object (an object)  locale description priority (a number)
--                          --
with blank rows for each thing.

To describe locale for (O - object):
    carry out the printing the locale description activity with O.

To set the/-- locale priority of (O - an object) to (N - a number):
    if O is a thing:
        if N is at most 0, now O is mentioned;
        if there is a notable-object of O in the Table of Locale Priorities:
            choose row with a notable-object of O in the Table of Locale Priorities;
            if N is at most 0, blank out the whole row;
            otherwise now the locale description priority entry is N;
        otherwise:
            if N is greater than 0:
                choose a blank row in the Table of Locale Priorities;
                now the notable-object entry is O;
                now the locale description priority entry is N;

§24. Printing the Locale Description. This is handled by the "printing the locale description" activity. The before stage works out which objects might be of interest; the for stage actually prints paragraphs; the after stage is initially empty, but can be used to insert all kinds of interesting information into a room description.

We count the paragraphs printed in a global variable, not an activity variable, since it needs to be consulted in sub-activities whose rules are outside what would be its scope; that doesn't matter, though, since locale descriptions are not nested. (If they were, the above table would fail in any case.)

Printing the locale description of something (documented at act_pld) is an activity.

The printing the locale description activity is accessible to Inter as
"PRINTING_LOCALE_DESCRIPTION_ACT".

The locale paragraph count is a number that varies.

Before printing the locale description (this is the initialise locale description rule):
    now the locale paragraph count is 0;
    repeat through the Table of Locale Priorities:
        blank out the whole row.

Before printing the locale description (this is the find notable locale objects rule):
    let the domain be the parameter-object;
    carry out the choosing notable locale objects activity with the domain;
    continue the activity.

For printing the locale description (this is the interesting locale paragraphs rule):
    let the domain be the parameter-object;
    sort the Table of Locale Priorities in locale description priority order;
    repeat through the Table of Locale Priorities:
        carry out the printing a locale paragraph about activity with the notable-object entry;
    continue the activity.

For printing the locale description (this is the you-can-also-see rule):
    let the domain be the parameter-object;
    let the mentionable count be 0;
    if the domain is a thing and the domain holds the player and the domain is falsely-unoccupied, continue the activity;
    repeat with item running through things:
        now the item is not marked for listing;
    repeat through the Table of Locale Priorities:
        if the locale description priority entry is greater than 0,
            now the notable-object entry is marked for listing;
        increase the mentionable count by 1;
    if the mentionable count is greater than 0:
        repeat with item running through things:
            if the item is mentioned:
                now the item is not marked for listing;
        begin the listing nondescript items activity with the domain;
        if the number of marked for listing things is 0:
            abandon the listing nondescript items activity with the domain;
        otherwise:
            if handling the listing nondescript items activity with the domain:
                if the domain is the location:
                    say "[We] " (A);
                otherwise if the domain is a supporter or the domain is an animal:
                    say "On [the domain] [we] " (B);
                otherwise:
                    say "In [the domain] [we] " (C);
                if the locale paragraph count is greater than 0:
                    say "[regarding the player][can] also see " (D);
                otherwise:
                    say "[regarding the player][can] see " (E);
                let the common holder be nothing;
                let contents form of list be true;
                repeat with list item running through marked for listing things:
                    if the holder of the list item is not the common holder:
                        if the common holder is nothing,
                            now the common holder is the holder of the list item;
                        otherwise now contents form of list is false;
                    if the list item is mentioned, now the list item is not marked for listing;
                filter list recursion to unmentioned things;
                if contents form of list is true and the common holder is not nothing,
                    list the contents of the common holder, as a sentence, including contents,
                        giving brief inventory information, tersely, not listing
                        concealed items, listing marked items only;
                otherwise say "[a list of marked for listing things including contents]";
                if the domain is the location, say " [here]" (F);
                say ".[paragraph break]";
                unfilter list recursion;
            end the listing nondescript items activity with the domain;
    continue the activity.

§25. Choosing Notable Locale Objects. By default, the notable objects are exactly the children of the domain, and they all have equal priority (1). Since table sorting is stable, and thus preserves the row order of rows with equal priority, the eventual order of listing is by default the same as the order in which things are added to the table, which in turn is the object-tree traversal order.

Choosing notable locale objects of something (documented at act_cnlo) is an activity.
The choosing notable locale objects activity is accessible to Inter as "CHOOSING_NOTABLE_LOCALE_OBJ_ACT".

For choosing notable locale objects (this is the standard notable locale objects rule):
    let the domain be the parameter-object;
    let the held item be the first thing held by the domain;
    while the held item is a thing:
        set the locale priority of the held item to 5;
        now the held item is the next thing held after the held item;
    continue the activity.

§26. Printing a Locale Paragraph. By default there are four kinds of "interesting" locale paragraph, and the following setup is fairly complicated because it implements conventions gradually built up between 1978 and 2008.

To recap, this activity is run on each notable thing in turn, in priority order. (It is only run on notable things for efficiency reasons.)

The basic principle is that, at every stage, we should consider an item only if it is not "mentioned" already. This will happen if it has been named by a previous paragraph, but also if it has been explicitly marked as such to get rid of it. In considering an item, we have three basic options:

Briefly, then, the following is the standard method:

Printing a locale paragraph about something (documented at act_plp) is an activity.
The printing a locale paragraph about activity is accessible to Inter as "PRINTING_LOCALE_PARAGRAPH_ACT".

For printing a locale paragraph about a thing (called the item)
    (this is the don't mention player's supporter in room descriptions rule):
    if the item encloses the player, set the locale priority of the item to 0;
    continue the activity.

For printing a locale paragraph about a thing (called the item)
    (this is the don't mention scenery in room descriptions rule):
    if the item is scenery, set the locale priority of the item to 0;
    continue the activity.

For printing a locale paragraph about a thing (called the item)
    (this is the don't mention undescribed items in room descriptions rule):
    if the item is undescribed:
        set the locale priority of the item to 0;
    continue the activity.

For printing a locale paragraph about a thing (called the item)
    (this is the set pronouns from items in room descriptions rule):
    if the item is not mentioned, set pronouns from the item;
    continue the activity.

For printing a locale paragraph about a thing (called the item)
    (this is the offer items to writing a paragraph about rule):
    if the item is not mentioned:
        if a paragraph break is pending, say "[conditional paragraph break]";
        carry out the writing a paragraph about activity with the item;
        if a paragraph break is pending:
            increase the locale paragraph count by 1;
            now the item is mentioned;
            say "[conditional paragraph break]";
    continue the activity.

For printing a locale paragraph about a thing (called the item)
    (this is the use initial appearance in room descriptions rule):
    if the item is not mentioned:
        if the item provides the property initial appearance and the
            item is not handled and the initial appearance of the item is
            not "":
            increase the locale paragraph count by 1;
            say "[initial appearance of the item]";
            say "[paragraph break]";
            if a locale-supportable thing is on the item:
                repeat with possibility running through things on the item:
                    now the possibility is marked for listing;
                    if the possibility is mentioned:
                        now the possibility is not marked for listing;
                say "On [the item] " (A);
                list the contents of the item, as a sentence, including contents,
                    giving brief inventory information, tersely, not listing
                    concealed items, prefacing with is/are, listing marked items only;
                say ".[paragraph break]";
            now the item is mentioned;
    continue the activity.

For printing a locale paragraph about a supporter (called the tabletop)
    (this is the initial appearance on supporters rule):
    repeat with item running through not handled things on the tabletop which
        provide the property initial appearance:
        if the item is not a person and the initial appearance of the item is not ""
            and the item is not undescribed:
            now the item is mentioned;
            say initial appearance of the item;
            say paragraph break;
    continue the activity.

Definition: a thing (called the item) is locale-supportable if the item is not
scenery and the item is not mentioned and the item is not undescribed.

For printing a locale paragraph about a thing (called the platform)
    (this is the describe what's on scenery supporters in room descriptions rule):
    if the platform is not a scenery supporter that does not enclose the player, continue the activity;
    let print a paragraph be false;
    let item be the first thing held by the platform;
    while item is not nothing begin;
      if the item is not scenery and the item is described and the platform does not conceal the item begin;
        if the item is mentioned begin;
          now the item is not marked for listing;
        else;
          now the item is marked for listing;
          now print a paragraph is true;
        end if;
      end if;
      now the item is the next thing held after the item;
    end while;
    if print a paragraph is true begin;
      set pronouns from the platform;
      increase the locale paragraph count by 1;
      say "On [the platform] " (A);
      list the contents of the platform, as a sentence, including contents,
        giving brief inventory information, tersely, not listing
        concealed items, prefacing with is/are, listing marked items only;
      say ".[paragraph break]";
    end if;
    continue the activity

For printing a locale paragraph about a thing (called the item)
    (this is the describe what's on mentioned supporters in room descriptions rule):
    if the item is mentioned and the item is not undescribed and the item is
        not scenery and the item does not enclose the player:
        if a locale-supportable thing is on the item:
            set pronouns from the item;
            repeat with possibility running through things on the item:
                now the possibility is marked for listing;
                if the possibility is mentioned:
                    now the possibility is not marked for listing;
            increase the locale paragraph count by 1;
            say "On [the item] " (A);
            list the contents of the item, as a sentence, including contents,
                giving brief inventory information, tersely, not listing
                concealed items, prefacing with is/are, listing marked items only;
            say ".[paragraph break]";
    continue the activity.

§27. Dialogue support.

Section 8 - Dialogue (for dialogue language element only)

Offering something is an activity on lists of dialogue choices.
The offering activity is accessible to Inter as "OFFERING_A_DIALOGUE_CHOICE".

For offering a list of dialogue choices (called L)
    (this is the default offering dialogue choices rule):
    let N be 1;
    repeat with C running through L:
        say "([N]) [textual content of C][line break]";
        increase N by 1.

Performing something is an activity on dialogue lines.
The performing activity is accessible to Inter as "PERFORMING_DIALOGUE".

The performing activity has an object called the speaker.

The performing activity has an object called the interlocutor.

The performing activity has a performance style called the style.

Before performing a dialogue line:
    now the speaker is the current dialogue line speaker;
    now the interlocutor is the current dialogue line interlocutor;
    now the style is the current dialogue line style.

For performing a dialogue line (called L)
    (this is the default dialogue performance rule):
    if L is narrated or L is elaborated or L is non-verbal:
        say "[textual content of L][line break]";
    otherwise:
        say "[The speaker]";
        if the interlocutor is something:
            say " (to [the interlocutor])";
        say ": '[textual content of L]'[line break]".