module.exports = {
  equal: function (a, b) {
    if (a === b) return true;
    if (a == null && b == null) return true;
    if (a == null || b == null) return false;
    if (Object.keys(a).length != Object.keys(b).length) return false;
    for(var key in a) {
      // Only compare one level deep
      if (a[key] !== b[key]) return false;
    }
    return true;
  },

  array: function (value) {
    return Array.isArray(value);
  },

  number: function (value) {
    if (typeof value === 'number') return true;
    if (typeof value === 'object' && Object.prototype.toString.call(value) === '[object Number]') return true;
    return false;
  },

  object: function (value) {
    if (!value) return false;
    return (typeof value === 'function' || typeof value === 'object');
  },

  string: function (value) {
    if (typeof value === 'string') return true;
    if (typeof value === 'object' && Object.prototype.toString.call(value) === '[object String]') return true;
    return false;
  }
};