# Zork Implentation Language
This document covers the Zork Implementation Language, as originally 
developed and used by Infocom for their games.

## Format
This document is written using CommonMark, a markup language. More 
information about CommonMark can be found at <http://commonmark.org>.

## Copyright And Licensing
Permission is granted to copy, distribute and/or modify this document 
under the terms of the GNU Affero General Public License as published 
by the Free Software Foundation ("FSF"), either version 3 of the 
License, or (at your option) any later version published by the FSF.

You should have received a copy of the GNU Affero General Public 
License along with this document. If not see 
<https://gnu.org/licenses/>.

## Definitions

A "definition" is used to describe a room, object, routine, etc. in or 
used by the game. Each definition consists of a number of properties, 
flags, and/or instructions. A program written in ZIL can be thought of 
as consisting of one or more of these definitions. Definitions, 
properties, flags, and instructions include brackets which must be 
correctly paired and nested.

## Syntax Definitions
Syntax definitions are used by the parser to determine valid sentence 
structures.

A simple example might be:

    <syntax xyzzy = v-magic>

Using this example, should the parser match the player's input to 
"xyzzy" then the PRSA is set to magic. PRSI and PRSO would be set to 
false.