Difference between revisions of "The Script Programming Language"

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(Created page with " The Script Programming Language Author: Jeff Stephenson<br /> Date: 4 April 1988 ==<br /> Introduction == The Script adventure game language is an object-oriented langua...")
 
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<div class="CodeBlockHeader">Code:</div>
 
<div class="CodeBlockHeader">Code:</div>
 
<syntaxhighlight lang="sci">
 
<syntaxhighlight lang="sci">
(procedure [parameter parameter ...]).</syntaxhighlight>
+
      (procedure [parameter parameter ...]).</syntaxhighlight>
  
 
The parameters to a procedure may themselves be expressions to be
 
The parameters to a procedure may themselves be expressions to be
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<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>
  
 
which would be written in infix notation as
 
which would be written in infix notation as
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<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>
  
 
All expressions are guaranteed to be evaluated from left to right. Thus,
 
All expressions are guaranteed to be evaluated from left to right. Thus,
 +
<div class="CodeBlockHeader">Code:</div>
 +
<syntaxhighlight lang="sci">
 +
      (= x 4)
 +
      (= y (/ (+= x 4) (/= x 2)))</syntaxhighlight>
  
(= x 4)
 
(= y (/ (+= x 4) (/= x 2)))
 
 
will result in y = 2 and x = 4.
 
will result in y = 2 and x = 4.
  
 
Comments in Script begin with a semi-colon, ';', and continue to the end of
 
Comments in Script begin with a semi-colon, ';', and continue to the end of
 
the line.
 
the line.

Revision as of 18:21, 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.