Example: ** Introductions - A system whereby both things and rooms can be given an "introduction", a tag line of text that is added the first time the player sees them in the room description if they are the main topic of a paragraph, or as an addendum to the object's description the first time it's examined. Introduction text can also be reviewed by the player with a THINK ABOUT command.

    "Introductions"

    Include Tailored Room Description by Emily Short.

    Section 1 - The Rules

    A thing has some text called the introduction. The introduction of a thing is usually "".
    A room has some text called the introduction. The introduction of a room is usually "".

    Rule for writing a paragraph about an as-yet-unknown introduceable thing (called special-target):
        carry out the writing a topic sentence about activity with the special-target;
        introduce the special-target;
        say paragraph break.
        
    After examining an as-yet-unknown introduceable thing (called special-target):
        introduce the special-target;
        say paragraph break.
    
    To introduce (special-target - an object):
        now the special-target is introduced;
        say "[introduction of the special-target]".

    Definition: a thing is introduceable if its introduction is not "".
    Definition: a room is introduceable if its introduction is not "".

    A thing can be as-yet-unknown or introduced. A thing is usually as-yet-unknown.
    A room can be as-yet-unknown or introduced. A room is usually as-yet-unknown.

    The first time looking rule is listed after new object description rule in the carry out looking rules.

    This is the first time looking rule:
        if location is introduceable and the location is as-yet-unknown
        begin;
            introduce the location;
            say paragraph break;
        end if.
    
    A description-concealing rule:
        now every thing which is held by an as-yet-unknown introduceable person is not marked for listing.
    
    Understand "think about [any introduceable introduced thing]" or "remember [any introduceable introduced thing]" as thinking about. Understand the commands "recall" or "consider" or "recollect" or "ponder" or "contemplate" as "remember".

    Thinking about is an action applying to one visible thing.

    Carry out thinking about:
        introduce the noun;
        say paragraph break.
    
    Section 2 - The Scenario

    The Maremma Breeding Ground is a room.

    Logar is an animal in Maremma Breeding Ground. "Logar stands here, waiting for instructions."
        The description is "A nine-month puppy, Logar is nonetheless a pretty sizable dog already."
        The introduction is "He's your latest acquisition in a large collection of work dogs."
    
    Logar carries a bone.
        The description of the bone is "Pretty well chewed already."
        The introduction of the bone is "That bone came out of a leg of lamb, but there's not much left on it."
    
    Test me with "z / look / x logar / think about logar / x bone".