anko / partser Goto Github PK

var p = require('.')

var space = p.regex(/\s/)

var sepBy = function (thing, separator) {
  var unit = p.map(
      p.seq(thing, p.times(separator, 0, Infinity)),
      function (results) { return results[0] })
  return p.times(unit, 0, Infinity)
}

var atom = p.regex(/[a-zA-Z0-9_-]+/)

var expression = p.eof

var list = p.map(
    p.seq(p.string('('), sepBy(atom, space), p.string(')')),
    function (results, environment) {
      // Expects the `environment` argument to be an object containing
      // functions for compiling AST, and registering new macros.  Also
      // contains a reference to the partsers making up the parser, so they can
      // be modified at run-time.

      var listContents = results[1]
      // Compile stuff here, call macros based on `listContents`, et cetera.
      // You know, classic central compiler "god switch statement".
      return listContents.map(environment.compile)
    })

var environment = {
  // Put whatever you want here.  For example: compiler functions, a table to
  // store macros, or a reference to the parser itself.
  compile: function (name) {
    return {
      type: 'Literal',
      name: name
    }
  }
}
var result = list('(a b c)', 0, environment) // Note the third argument.

console.log(result.value)

[ { type: 'Literal', name: 'a' },
  { type: 'Literal', name: 'b' },
  { type: 'Literal', name: 'c' } ]