AUTOHIT 2003 

SIMLANGUAGE GUIDE DOCUMENTATION

Copyright Erich P Gatejen (c) 1989,1997,2003,2004
See license for details.

WIP.  See the other documents for more information.

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CONCEPTS
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- Every program is well formed XML.  The DTD can be found at /lib/dtd/sim.dtd.

- Every program can be treated as a subroutine.  The <io> section describes
the input parameters (<input> and <buffer>) and output.  The input parameters
are just variables that the program expects to find in scope.

- NOTE: The compiler and runtime don't currently verify that the input
parameters are in scope.  Also, any variable in scope can be used by the 
program.  So, technically, the inputs are not needed.  HOWEVER, the <output>
*is* required!  Since subroutine calls work life functions, they can return a
a result.  The <output> tells it which local variable to return as the result. 

<!ENTITY lt     "&#38;#60;">
<!ENTITY gt     "&#62;">
<!ENTITY amp    "&#38;#38;">
<!ENTITY apos   "&#39;">
<!ENTITY quot   "&#34;">
 
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TAGS
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HEADER
<sim>
	<info>
		<name>
		<note>
		<version>
		<io>
			<input>
			<buffer>
			<output>	// defines the output var
	<code>
		<block>
		<buffer>
		<call>
		<exec>
		<for>
		<input>			// always create new
		<if>
		<math>
		<set>			// create new only if tagged
		<subroutine>
		<while>
		<return>		// force an exit from the stript
		<goto>
		<label>
		<assert>
		<method>


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COMMAND LIST
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-- HEADER -------------------------------------------------------------

Every program must begin with this header.  There are no exceptions:
	<?xml version="1.0"?>
	<!DOCTYPE sim SYSTEM "sim.dtd">

You may follow that with an optional comment section:
	<!--
		comment here.  This is a standard XML comment.
	-->

-- <sim> --------------------------------------------------------------

Wraps the entire program.  It must contain one <info> section and one <code>
section.


-- <info> --------------------------------------------------------------

Contains information about the program.  It has the following sections in 
the sequence described:
		<name>		REQUIRED
		<note>		REQUIRED
		<version>	REQUIRED
		<io>		REQUIRED - but may be empty.


-- <code> --------------------------------------------------------------

Contains the actual executable.  It must have at least one instruction.
The instructions are as follows:
		<block>
		<buffer>
		<call>
		<exec>
		<for>
		<input>
		<if>
		<math>
		<set>
		<subroutine>
		<while>
		<return>
		<goto>
		<label>
		<assert>

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ANNOTATED EXAMPLES
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