Javascript Generator

A program for generating widely varied, syntactically valid Javascript source code conforming to the ECMA-262 Standard.

Requires Haskell, easily installed at The Haskell Platform

Getting the Code

The latest version of the code can always be gotten from github, either by cloning it with git:

git clone git://github.com/rictic/generatejs.git
cd generatejs

Or by downloading a tarball:

curl -L http://github.com/rictic/generatejs/tarball/master > generatejs.tar.gz
tar -xzf generatejs.tar.gz
cd *generatejs*/

Installation

Installation should be as simple as

cabal update && cabal install

Running

generatejs [--stdout] <number-of-programs-to-create>

If you include --stdout, the programs are written to standard out, one to a line.

Otherwise it will create a directory gen/ in your current directory. This directory will in turn be filled with numbered subdirectories, each of which holds up to 20000 numbered js programs. This is done to keep the filesystem from freaking out from too many files in any one directory.

Hacking

The command line runner is in generateJS.hs, the actual generation code is in jsgenerator.js.

The code is written in a declarative style, with a pretty direct mapping from the productions in the standard to Symbols in the code.

i.e. the production

SignedInteger ::: 
    DecimalDigits
    + DecimalDigits
    - DecimalDigits

becomes

signedInteger = Nonterminal [
    [decimalDigits],
    [Terminal "+", decimalDigits],
    [Terminal "-", decimalDigits]]

I found it helpful to construct a few Symbols with Terminal and Nonterminal and pass the result to getAll until I was sure I had it worked out.