beppe9000/LICENSE.txt

## README.md

      
    Raw
  

              README.md
            
          
    A turing machine in 79! bytes of javascript

version 1.3
Original idea by http://swizec.com/blog/a-turing-machine-in-133-bytes-of-javascript/swizec/3069#
Demo http://jsfiddle.net/WcjZ5/6/
Thx @subzey, @Kambfhase, @tsaniel for help!

  
## annotated.js
// added some curly braces for readability
function(
  a, // {Object} program @see test.html for details
  b, // {Number[]} tape
  c, // {String} end state
  d, // {String} start state
  e  // [{Number} = 0] caret position
) {

while(
  d < c // while ! eof program
) {
    /* 'e |= 0' - if e is undefined - reset to 0 else leave as is */
    with (/* q = */a[d][b[e |= 0] || "B"]) { // push current program statement aka "q" to the top of current scope
      b[e] = w, // chenge symbol under caret, w is the item of "q"
      e += m, // move caret by ..., m is the item of "q"
      d = n; // jump to next state, n is the item of "q"
    }
}

return b

}

## index.js
function(a,b,c,d,e){while(d<c)with(a[d][b[e|=0]||"B"])b[e]=w,e+=m,d=n;return b}

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

 Copyright (C) 2011 YOUR_NAME_HERE <YOUR_URL_HERE>

 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": "turing_machine",

  "description": "A turing machine implementation",

  "keywords": [
    "turing_machine"
  ]
}

## test.html
<!DOCTYPE html>
<title>Foo</title>
<div>Expected value: <b>1,1,1,0,1,1,1</b></div>
<div>Actual value: <b id="ret"></b></div>
<script>

  var tm = function(a,b,c,d,e){while(d<c)with(a[d][b[e|=0]||"B"])b[e]=w,e+=m,d=n;return b};

  var program = {"q0": {"1": {"w": "B", "m": 1, "n": "q1"}},
 "q1": {"1": {"w": "1", "m": 1, "n": "q1"},
        "0": {"w": "0", "m": 1, "n": "q2"},
        "B": {"w": "0", "m": 1, "n": "q2"}},
 "q2": {"1": {"w": "1", "m": 1, "n": "q2"},
        "B": {"w": "1", "m": -1, "n": "q3"}},
 "q3": {"1": {"w": "1", "m": -1, "n": "q3"},
        "0": {"w": "0", "m": -1, "n": "q3"},
        "B": {"w": "1", "m": 1, "n": "q4"}},
 "q4": {"1": {"w": "B", "m": 1, "n": "q1"},
        "0": {"w": "0", "m": 1, "n": "q5"}}};

  var tape = [1,1,1];

  document.getElementById("ret").innerHTML = tm(program, tape, "q5", "q0", 0);
</script>
	// added some curly braces for readability
	function(
	a, // {Object} program @see test.html for details
	b, // {Number[]} tape
	c, // {String} end state
	d, // {String} start state
	e // [{Number} = 0] caret position
	) {

	while(
	d < c // while ! eof program
	) {
	/* 'e \|= 0' - if e is undefined - reset to 0 else leave as is */
	with (/* q = */a[d][b[e \|= 0] \|\| "B"]) { // push current program statement aka "q" to the top of current scope
	b[e] = w, // chenge symbol under caret, w is the item of "q"
	e += m, // move caret by ..., m is the item of "q"
	d = n; // jump to next state, n is the item of "q"
	}
	}

	return b

	}
	DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE
	Version 2, December 2004

	Copyright (C) 2011 YOUR_NAME_HERE <YOUR_URL_HERE>

	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": "turing_machine",

	"description": "A turing machine implementation",

	"keywords": [
	"turing_machine"
	]
	}
	<!DOCTYPE html>
	<title>Foo</title>
	<div>Expected value: <b>1,1,1,0,1,1,1</b></div>
	<div>Actual value: <b id="ret"></b></div>
	<script>

	var tm = function(a,b,c,d,e){while(d<c)with(a[d][b[e\|=0]\|\|"B"])b[e]=w,e+=m,d=n;return b};

	var program = {"q0": {"1": {"w": "B", "m": 1, "n": "q1"}},
	"q1": {"1": {"w": "1", "m": 1, "n": "q1"},
	"0": {"w": "0", "m": 1, "n": "q2"},
	"B": {"w": "0", "m": 1, "n": "q2"}},
	"q2": {"1": {"w": "1", "m": 1, "n": "q2"},
	"B": {"w": "1", "m": -1, "n": "q3"}},
	"q3": {"1": {"w": "1", "m": -1, "n": "q3"},
	"0": {"w": "0", "m": -1, "n": "q3"},
	"B": {"w": "1", "m": 1, "n": "q4"}},
	"q4": {"1": {"w": "B", "m": 1, "n": "q1"},
	"0": {"w": "0", "m": 1, "n": "q5"}}};

	var tape = [1,1,1];

	document.getElementById("ret").innerHTML = tm(program, tape, "q5", "q0", 0);
	</script>