brainfuck.html

   1 <?xml version="1.0" encoding="UTF-8"?>
   2 <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN" "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">
   3 <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en">
   4 <head>
   5     <meta content="text/html; charset=utf-8" http-equiv="Content-Type"/>
   6     <link rel="stylesheet" href="style/pixelless.css" type="text/css"/>
   7     <script type="text/javascript" src="script/util.js"></script>
   8     <title>Brainfuck</title>
   9 </head>
  10 <body>
  11 <div id="container">
  12     <div class="content header">
  13         <h1>Brainfuck</h1>
  14     </div>
  15
  16     <div class="content">
  17         <p><a href="http://en.wikipedia.org/wiki/Brainfuck">Brainfuck</a> "IDE"</p>
  18         <a href="#" onclick="run(); return false;" id="runit" style="text-decoration: none">&#x25B6; Run</a><br/>
  19
  20         <pre>Clear: <a href="javascript:add(this)" onclick="add(this); return false;">[-]</a>                          Clear prev no zero: <a
  21                 href="javascript:add(this)" onclick="add(this); return false;">[[-]&lt;]</a>
  22 Rewind: <a href="javascript:add(this)" onclick="add(this); return false;">[&lt;]&gt;</a>                        Fast-forward: <a
  23                     href="javascript:add(this)" onclick="add(this); return false;">[&gt;]&lt;</a>
  24 Cat: <a href="javascript:add(this)" onclick="add(this); return false;">,[.,]</a>                          Moving the pointer: <a
  25                     href="javascript:add(this)" onclick="add(this); return false;">&gt;,[.&gt;,]</a>
  26 Add: <a href="javascript:add(this)" onclick="add(this); return false;">[-&gt;+&lt;]</a> or <a
  27                     href="javascript:add(this)" onclick="add(this); return false;">[-&gt;+&gt;+&lt;&lt;]&gt;&gt;[-&lt;&lt;+&gt;&gt;]</a>  Copy: <a
  28                     href="javascript:add(this)" onclick="add(this); return false;">[-]&gt;[-]&lt;&lt;[-&gt;+&gt;+&lt;&lt;]&gt;&gt;[-&lt;&lt;+&gt;&gt;]</a></pre>
  29
  30
  31         <div id="memory" style="float:right"></div>
  32         <div id="hint" style="clear: right; float:right">
  33             &gt; move right<br/>
  34             &lt; move left<br/>
  35             + increment data<br/>
  36             - decrement data<br/>
  37             . output<br/>
  38             , input<br/>
  39             [ if data is zero jump after matching ]<br/>
  40             ] id data is not zero goto matching [<br/>
  41         </div>
  42         <label>Input: <input type="text" id="input" value="" style="margin-bottom: .2em; font-family:monospace; width:80ex"/></label><br/>
  43         <textarea id="edit" cols="80" rows="14"></textarea>
  44         <textarea id="out" cols="80" rows="6" readonly="readonly"></textarea>
  45     </div>
  46 </div>
  47 <div id="footer">
  48     <div class="content">
  49         &copy; Copyright
  50     </div>
  51 </div>
  52 <script type="text/javascript" language="JavaScript">
  53     var memoryLimit = 30000;
  54     var execLimit = 10000;
  55
  56     function add(obj)
  57     {
  58         var target = document.getElementById('edit');
  59         var x = target.selectionStart;
  60         var value = obj.innerHTML.replace(/&lt;/g, "<").replace(/&gt;/g, ">");
  61         var before = target.value.substring(0, x);
  62         var after = target.value.substr(target.selectionEnd);
  63         target.value = before + value + after;
  64         target.selectionStart = x + value.length;
  65         target.selectionEnd = x + value.length;
  66         target.focus();
  67     }
  68
  69     function run()
  70     {
  71         function add(n)
  72         {
  73             var x = (memory[addr] || 0) + n;
  74             if (x > 255)x = 0;
  75             if (x < 0)x = 255;
  76             memory[addr] = x;
  77             return x;
  78         }
  79
  80         function get_input()
  81         {
  82             var r = input[inpos++];
  83             if (r === undefined) return 0; // EOF
  84             return r.charCodeAt(0);
  85         }
  86
  87         var inpos = 0;
  88         var input = document.getElementById('input').value;
  89         var src = document.getElementById('edit').value;
  90
  91         var addr = 0;
  92         var memory = [];
  93         var out = '';
  94
  95         var line = 1;
  96         var column = 0;
  97
  98         var loops = [];
  99         var steps = 0;
 100         var loopstack = [];
 101
 102         var i = -1, n = src.length;
 103         while (++i < n)
 104         {
 105             ++column;
 106             var op = src[i];
 107             switch (op) {
 108                 case '[':
 109                     loops[i] = 0;
 110                     loopstack.push(i);
 111
 112                     break;
 113
 114                 case ']':
 115                     var loop = loopstack.pop();
 116
 117                     if (loop === undefined)
 118                         throw new Error(['Loop brace mismatch at line', line, ', column', column].join(' '));
 119                     loops[loop] = i;
 120
 121                     break;
 122
 123                 case '\n':
 124                     ++line;
 125                     column = 1;
 126
 127                     break;
 128             }
 129         }
 130
 131         delete loopstack;
 132
 133         line = 1;
 134         column = 0;
 135         i = -1;
 136         n = src.length;
 137         while (++i < n)
 138         {
 139             if (++steps > execLimit)
 140                 throw new Error(['Execution limit of ', execLimit, ' cycles exceded at line ', line, ', column', column].join(' '));
 141
 142             ++column;
 143             var op = src[i];
 144             switch (op) {
 145                 case '\n':
 146                     ++line;
 147                     column = 0;
 148
 149                     break;
 150
 151                 case '<':
 152                     if (--addr < 0)
 153                         throw new Error(['Address underrun at line', line, ', column', column].join(' '));
 154
 155                     break;
 156
 157                 case '>':
 158                     if (++addr > memoryLimit)
 159                         throw new Error(['Address overrun at line', line, ', column', column].join(' '));
 160
 161                     break;
 162
 163                 case '-':
 164                     add(-1);
 165
 166                     break;
 167
 168                 case '+':
 169                     add(1);
 170
 171                     break;
 172
 173                 case '[':
 174                     if (!memory[addr])
 175                         i = loops[i];
 176
 177                     break;
 178
 179                 case ']':
 180                     i = loops.indexOf(i);
 181                     if (i == -1)
 182                         throw new Error(['Unxepected loop error at line', line, ', column', column].join(' '));
 183
 184                     --i;
 185                     break;
 186
 187                 case '.':
 188                     if (memory[addr] < 32)
 189                         out += memory[addr].toString() + ' ';
 190                     else
 191                         out += String.fromCharCode(memory[addr]);
 192
 193                     break;
 194
 195                 case ',':
 196                     memory[addr] = get_input();
 197
 198                     break;
 199             }
 200         }
 201
 202         document.getElementById('memory').innerHTML = memory.map(function(x, n) {
 203             if (n == addr)return '<u>' + x + '</u>'; else return x;
 204         });
 205         document.getElementById('out').value = out;
 206     }
 207
 208
 209 </script>
 210 </body>
 211 </html>