tlrobinson/LICENSE.txt

## README.md

      
    Raw
  

              README.md
            
          
    Prefix notation calculator parser

This is a very simple prefix notation calculator implementation in JavaScript, for the purpose of demonstrating a simple lexer, parser, compiler, and interpreter for my JSConf.eu talk, "JavaScript Compilers for Fun and Profit".
They're available packaged together here:

https://gist.github.com/1257254

mini-calc-golfed.js contains each component JS-golfed down to < 140 bytes.
And individually as 140byt.es forks here:

Lexer: https://gist.github.com/1259461
Parser: https://gist.github.com/1259487
Interpreter: https://gist.github.com/1259489
Compiler: https://gist.github.com/1259490


## annotated.js
function(tokens) {
    var nodes = [];
    tokens.shift();
    while (token = tokens.shift()) {
        if (token == "(") {
            // unget the paren and recurse
            tokens.unshift(token);
            nodes.push(parse(tokens));
        } else if (token == ")") {
            return nodes;
        } else {
            nodes.push(token);
        }
    }
}

## index.js
function p(a,b,c){c=[];a.shift();while(b=a.shift()){if(b=="("){a.unshift(b);c.push(p(a))}else if(b==")"){return c}else{c.push(b)}}}

## LICENSE.txt
            DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE
                    Version 2, December 2004

 Copyright (C) 2011 Tom Robinson <http://tlrobinson.net/>

 Everyone is permitted to copy and distribute verbatim or modified
 copies of this license document, and changing it is allowed as long
 as the name is changed.

            DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE
   TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION

  0. You just DO WHAT THE FUCK YOU WANT TO.

## package.json
{
  "name": "theNameOfYourLibWhichMustBeAValidCamelCasedJavaScriptIdentifier",

  "description": "This should be a short description of your entry.",

  "keywords": [
    "five",
    "descriptive",
    "keywords",
    "or",
    "fewer"
  ]
}

## test.html
<!DOCTYPE html>
<title>Prefix notation calculator parser</title>
<script>
    function repl(c,t,h,r){h=[t||""];while(s=prompt(h.slice(-10).join("\n"))){try{r=(c||eval)(s)}catch(e){r=e}h.push(""+r)}}

    // lexer
    function l(s){return s.match(/\(|\)|\d+(\.\d+)?|\w+|[+*\/-]/g).map(function(t){return /^\d/.test(t)?parseFloat(t):t})}
    // parser
    function p(a,b,c){c=[];a.shift();while(b=a.shift()){if(b=="("){a.unshift(b);c.push(p(a))}else if(b==")"){return c}else{c.push(b)}}}

    repl(function(s) { return JSON.stringify(p(l(s))); }, "Prefix notation calculator parser, e.x. '(+ 1 (* 2 3))'")
</script>
	function(tokens) {
	var nodes = [];
	tokens.shift();
	while (token = tokens.shift()) {
	if (token == "(") {
	// unget the paren and recurse
	tokens.unshift(token);
	nodes.push(parse(tokens));
	} else if (token == ")") {
	return nodes;
	} else {
	nodes.push(token);
	}
	}
	}
	DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE
	Version 2, December 2004

	Copyright (C) 2011 Tom Robinson <http://tlrobinson.net/>

	Everyone is permitted to copy and distribute verbatim or modified
	copies of this license document, and changing it is allowed as long
	as the name is changed.

	DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE
	TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION

	0. You just DO WHAT THE FUCK YOU WANT TO.
	{
	"name": "theNameOfYourLibWhichMustBeAValidCamelCasedJavaScriptIdentifier",

	"description": "This should be a short description of your entry.",

	"keywords": [
	"five",
	"descriptive",
	"keywords",
	"or",
	"fewer"
	]
	}
	<!DOCTYPE html>
	<title>Prefix notation calculator parser</title>
	<script>
	function repl(c,t,h,r){h=[t\|\|""];while(s=prompt(h.slice(-10).join("\n"))){try{r=(c\|\|eval)(s)}catch(e){r=e}h.push(""+r)}}

	// lexer
	function l(s){return s.match(/\(\|\)\|\d+(\.\d+)?\|\w+\|[+*\/-]/g).map(function(t){return /^\d/.test(t)?parseFloat(t):t})}
	// parser
	function p(a,b,c){c=[];a.shift();while(b=a.shift()){if(b=="("){a.unshift(b);c.push(p(a))}else if(b==")"){return c}else{c.push(b)}}}

	repl(function(s) { return JSON.stringify(p(l(s))); }, "Prefix notation calculator parser, e.x. '(+ 1 (* 2 3))'")
	</script>