Difference between revisions of "The Script Programming Language"
| Line 13: | Line 13: | ||
As is Lisp, Script is based on parenthesized expressions which return values. An expression is of the form | As is Lisp, Script is based on parenthesized expressions which return values. An expression is of the form | ||
| + | <blockquote> | ||
<div class="CodeBlockHeader">Code:</div> | <div class="CodeBlockHeader">Code:</div> | ||
<syntaxhighlight lang="sci"> | <syntaxhighlight lang="sci"> | ||
| − | (procedure [parameter parameter ...]).</syntaxhighlight> | + | (procedure [parameter parameter ...]). |
| + | </syntaxhighlight> | ||
| + | </blockquote> | ||
The parameters to a procedure may themselves be expressions to be evaluated, and may be nested until you lose track of the parentheses. | The parameters to a procedure may themselves be expressions to be evaluated, and may be nested until you lose track of the parentheses. | ||
| Line 21: | Line 24: | ||
Unlike Lisp, the procedure itself may NOT be the result of an evaluation. An example of an expression is | Unlike Lisp, the procedure itself may NOT be the result of an evaluation. An example of an expression is | ||
| + | <blockquote> | ||
<div class="CodeBlockHeader">Code:</div> | <div class="CodeBlockHeader">Code:</div> | ||
<syntaxhighlight lang="sci"> | <syntaxhighlight lang="sci"> | ||
| − | (+ (- y 2) (/ x 3))</syntaxhighlight> | + | (+ (- y 2) (/ x 3)) |
| + | </syntaxhighlight> | ||
| + | </blockquote> | ||
which would be written in infix notation as | which would be written in infix notation as | ||
| + | <blockquote> | ||
<div class="CodeBlockHeader">Code:</div> | <div class="CodeBlockHeader">Code:</div> | ||
<syntaxhighlight lang="sci"> | <syntaxhighlight lang="sci"> | ||
| − | (y - 2) + (x / 3).</syntaxhighlight> | + | (y - 2) + (x / 3). |
| + | </syntaxhighlight> | ||
| + | </blockquote> | ||
All expressions are guaranteed to be evaluated from left to right. Thus, | All expressions are guaranteed to be evaluated from left to right. Thus, | ||
| + | |||
| + | <blockquote> | ||
<div class="CodeBlockHeader">Code:</div> | <div class="CodeBlockHeader">Code:</div> | ||
<syntaxhighlight lang="sci"> | <syntaxhighlight lang="sci"> | ||
(= x 4) | (= x 4) | ||
| − | (= y (/ (+= x 4) (/= x 2)))</syntaxhighlight> | + | (= y (/ (+= x 4) (/= x 2))) |
| + | </syntaxhighlight> | ||
| + | </blockquote> | ||
will result in y = 2 and x = 4. | will result in y = 2 and x = 4. | ||
Revision as of 18:23, 28 November 2015
The Script Programming Language
Author: Jeff Stephenson
Date: 4 April 1988
Introduction
The Script adventure game language is an object-oriented language with a Lisp-like syntax. It is compiled by the sc compiler into the pseudo-code which is used by the interpreter, sci.
We will begin our discussion of the language with its basic Lisp-like characteristics, then go on to the object-oriented parts of the language.
As is Lisp, Script is based on parenthesized expressions which return values. An expression is of the form
Code:(procedure [parameter parameter ...]).
The parameters to a procedure may themselves be expressions to be evaluated, and may be nested until you lose track of the parentheses.
Unlike Lisp, the procedure itself may NOT be the result of an evaluation. An example of an expression is
Code:(+ (- y 2) (/ x 3))
which would be written in infix notation as
Code:(y - 2) + (x / 3).
All expressions are guaranteed to be evaluated from left to right. Thus,
Code:(= x 4) (= y (/ (+= x 4) (/= x 2)))
will result in y = 2 and x = 4.
Comments in Script begin with a semi-colon, ';', and continue to the end of the line.
