Jörgen Cederlöf: brainfuck.xslt

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Index Photos Hacks/ Wotsap Overslack maildird verifygpgmail jcbt jcfilesize typesetpy zeno.qcl brainfuck.xslt Noid Patches Cryptography	brainfuck.xslt Sometimes it is fun to implement something using tools extremely unsuitable for the job. Especially if what is implemented is quite pointless in itself. When learning XSLT I decided that implementing a Brainfuck interpreter in pure XSLT would be non-trivial, fun, a good learning experience, and completely useless. Download brainfuck.xslt version 0.9 (sig) The brainfuck.xslt stylesheet transforms a brainfuck xml document to an output brainfuck xml document, by running the Brainfuck program in the /brainfuck/code element with /brainfuck/input as input. Be sure to escape the brainfuck statements properly as XML requires. Characters in the code element which are not brainfuck instructions are ignored. No xslt extensions are used, just plain xslt 1.0. The array is dynamically resized on the right (>) side when needed and can be considered to be of infinite size. To see the array for every statement processed, pass parameter "debug" with a value evaluating to true() to the stylesheet. Be aware that, since the brainfuck.xslt stylesheet works with recursion, some xslt processors will eat lots of memory and/or segfault when running large complicated Brainfuck programs. For example, the documents: <?xml version="1.0" encoding="iso-8859-1"?> <brainfuck> <code>,[.,]</code> <input>Hello World!</input> </brainfuck> and: <?xml version="1.0" encoding="iso-8859-1"?> <brainfuck> <code><![CDATA[ ++++++++++[>+++++++>++++++++++>+++>+<<<<-] >++.>+.+++++++..+++.>++.<<+++++++++++++++. >.+++.------.--------.>+. ]]></code> </brainfuck> both produce the document: <?xml version="1.0" encoding="iso-8859-1"?> <brainfuck> <result>Hello World!</result> </brainfuck> The document: <?xml version="1.0" encoding="iso-8859-1"?> <brainfuck> <code><![CDATA[ ,>,,>++++++++[<------<------>>-] <<[>[>+>+<<-]>>[<<+>>-]<<<-] >>>++++++[<++++++++>-],<.>. ]]></code> <input>2*3</input> </brainfuck> will produce: <?xml version="1.0" encoding="iso-8859-1"?> <brainfuck> <result>6</result> </brainfuck> The brainfuck.xslt stylesheet is available at http://www.lysator.liu.se/~jc/hacks/brainfuck.xslt
Jörgen Cederlöf <jc@lysator.liu.se>

The brainfuck.xslt stylesheet transforms a brainfuck xml document to an output brainfuck xml document, by running the Brainfuck program in the /brainfuck/code element with /brainfuck/input as input. Be sure to escape the brainfuck statements properly as XML requires. Characters in the code element which are not brainfuck instructions are ignored.

No xslt extensions are used, just plain xslt 1.0.

The array is dynamically resized on the right (>) side when needed and can be considered to be of infinite size. To see the array for every statement processed, pass parameter "debug" with a value evaluating to true() to the stylesheet.

Be aware that, since the brainfuck.xslt stylesheet works with recursion, some xslt processors will eat lots of memory and/or segfault when running large complicated Brainfuck programs.

For example, the documents:

  <?xml version="1.0" encoding="iso-8859-1"?>
  <brainfuck>
    <code>,[.,]</code>
    <input>Hello World!</input>
  </brainfuck>

and:

  <?xml version="1.0" encoding="iso-8859-1"?>
  <brainfuck>
    <code><![CDATA[
      ++++++++++[>+++++++>++++++++++>+++>+<<<<-]
      >++.>+.+++++++..+++.>++.<<+++++++++++++++.
      >.+++.------.--------.>+.
      ]]></code>
  </brainfuck>

both produce the document:

  <?xml version="1.0" encoding="iso-8859-1"?>
  <brainfuck>
    <result>Hello World!</result>
  </brainfuck>

The document:

  <?xml version="1.0" encoding="iso-8859-1"?>
  <brainfuck>
    <code><![CDATA[
      ,>,,>++++++++[<------<------>>-]
      <<[>[>+>+<<-]>>[<<+>>-]<<<-]
      >>>++++++[<++++++++>-],<.>.
      ]]></code>
    <input>2*3</input>
  </brainfuck>

will produce:

  <?xml version="1.0" encoding="iso-8859-1"?>
  <brainfuck>
    <result>6</result>
  </brainfuck>

The brainfuck.xslt stylesheet is available at http://www.lysator.liu.se/~jc/hacks/brainfuck.xslt

brainfuck.xslt

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