isLaziable.js 705 Bytes
var LazyWrapper = require('./LazyWrapper'),
    getData = require('./getData'),
    getFuncName = require('./getFuncName'),
    lodash = require('../chain/lodash');

/**
 * Checks if `func` has a lazy counterpart.
 *
 * @private
 * @param {Function} func The function to check.
 * @returns {boolean} Returns `true` if `func` has a lazy counterpart, else `false`.
 */
function isLaziable(func) {
  var funcName = getFuncName(func),
      other = lodash[funcName];

  if (typeof other != 'function' || !(funcName in LazyWrapper.prototype)) {
    return false;
  }
  if (func === other) {
    return true;
  }
  var data = getData(other);
  return !!data && func === data[0];
}

module.exports = isLaziable;