This was a brief attempt at making a text adventure game engine. It's 
not complete and not in active development. Using the logic that if 
it took more than 3 minutes to make it's worth sharing I'm sharing it 
in case anyone else is interested and wants to continue with it.

----------------------------

Text adventure games contain, among other things, rooms and objects. A 
room simply means a particular location or scene in the game, which 
usually corresponds to the name shown to the player as they move 
around. Let's consider the following example:

my $rooms = {
    $the_kitchen = {
        name        => 'Kitchen',
        description => 'This was once an exquisite kitchen.',
        east        => 'living_room',
        action      => 'kitchen_routine',
        flags       => [ 'light', ],
    },
};

my $objects = {
    table => {
        name => 'kitchen table',
        description => 'It looks like something right out of the 1950s: Green formica and chrome legs.',
        location => 'kitchen',
        action   => 'table_routine',
	flags    => [ 'surface', ],
    },
    apple => {
        name     => 'apple',
        location => 'table',
        action   => 'apple_routine',
	flags    => [ 'vowel', 'take', ],
    },
};

The above established a few things: There is a room. It has an 
internal name of the_kitchen, but the name shown the the player is 
"Kitchen". It also has a description. From here the the player can go 
east into the room with the internal name living_room. Finally, there 
is a subroutine called kitchen_routine. That subroutine will be called 
at various points in the game. More on that later.

The above also creates a table, located in the kitchen. Finally, there 
is also an apple on the table in the kitchen. The table has been 
flagged to indicate that it is a surface that things can be placed on, 
and the apple has been flagged to indicate that the player an take it. 
This provides the game engine with important information about what 
objects can be taken, and what objects can be placed on other objects. 
(The apple doesn't have the surface flag set, because it would not 
make sense to be able to put the table on the apple. Also, the table 
does not have the take bit set because the table is very heavy and the 
player shouldn't be able to move it.) Rooms and objects can have an 
arbitrary number of flags, any of which may be added or removed while 
the game is in progress. Similar to the kitchen, each of these also 
has a subroutine associated with them. The location of objects may 
change during game play. The player might take the apple, for example, 
and it would no longer be on the table. Or perhaps the light in the 
kitchen is turned off, so it no longer has the "light" flag. Thus, the 
information above establishes information about rooms and objects as 
they exist at the start of the game.

--
Copyright (C) 2018 Jason Self <j@jxself.org>

You can redistribute and/or modify this file under the terms of the 
GNU Affero General Public License as published by the Free Software 
Foundation, either version 3 of the License, or (at your option) any 
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WITHOUT ANY WARRANTY; without even the implied warranty of 
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