Allow for fuzzy path matching.

fuzzPath.js

// people[*]["firstName" | "lastName" | "fullName"]
// people[*][firstName | lastName | fullName]
// people[*][/^(first|last|full)Name$/]
// people.*[/^(first|last|full)Name$/]
// people.*./^(first|last|full)Name$/
// people[#0..9..2#]

// var RGX_REGEXES = /\/((?:[^\\\/]+|\\.)+)\/(i?)/; // match regexes (rgxBody, rgxFlags)
// var RGX_STRINGS = /("(?:[^\\"]+|\\.)*")/; // match strings (strRaw)
// var RGX_ASTERISKS = /(\*)/; // match * (isAsterisk)
// var RGX_INTEGERS = /(#(?:(-?\d+|\?)\.\.(-?\d+|\?)(?:\.\.(-?\d+))?#)?)/; // match integer ranges (isRange, numMin, numMax, numStep)
// var RGX_SIMPLE_NAMES = /([1-9]\d+|[\$_A-Za-z][\$\w]*)/; // match simple names and integers (strName)
var RGX_NAMES = /\/((?:[^\\\/]+|\\.)+)\/(i?)|("(?:[^\\"]+|\\.)*")|(\*)|(#(?:(-?\d+|\?)\.\.(-?\d+|\?)(?:\.\.(-?\d+))?#)?)|(0|[1-9]\d*|[\$_A-Za-z][\$\w]*)/g;
function fuzzPath(strPath) {
  var level, candidate, levels = [];
  strPath = strPath.replace(
    RGX_NAMES,
    function(source, expBody, expFlags, strRaw, isAsterisk, isRange, numMin, numMax, numStep, strName, index, strPath) {
      var isNewLevel = /(^|\.|\[)\s*$/.test(strPath.slice(0, index));
      if (isNewLevel) {
        levels.push(level = []);
      }

      if (expBody) {
        candidate = {
          type: 'RegExp',
          value: new RegExp(expBody, expFlags)
        };
      }
      else if (strRaw || strName) {
        candidate = {
          type: 'String',
          value: strName || JSON.parse(strRaw.replace(/\\(?:(0)|x([\dA-F]{2}))/g, '\\u00$1$1$2'))
        };
      }
      else if (isAsterisk) {
        candidate = { type: 'Anything' };
      }
      else if (isRange) {
        if ((numMin || '?') === '?' && (numMax || '?') === '?') {
          if ((numStep || '?') !== '?') {
            throw new Error('"?..?" is an invalid fuzz range.');
          }
          candidate = { type: 'RegExp', value: /^-(?:0|[1-9]\d*)$/ };
        }
        else {
          var isBasedOnMin = numMin !== '?';
          numMin = isBasedOnMin ? +numMin : -Infinity;
          numMax = numMax === '?' ? Infinity : +numMax;
          numStep = numStep === '?' ? 1 : +numStep;
          candidate = {
            type: 'Function',
            value: function (key) {
              if (/^-(?:0|[1-9]\d*)$/.test(key)) {
                key = +key;
                return (numStep === 1 || ((isBasedOnMin ? key - numMin : (numMax - key)) / numStep) % 1 === 0) && numMin <= key && key <= numMax;
              }
              return false;
            }
          }
        }
      }
      candidate.source = source;

      level.push(candidate);
      return '@';
    }
  );

  if (!/^(?:\.@(?:\|@)*|\[@(?:\|@)*\])+$/.test(strPath.replace(/\s+/g, '').replace(/^[^\[]/, '.$&'))) {
    throw new Error('This expression cannot be reduced any further:\t' + strPath);
  }

  return levels;
}