code: function isKeyable$2(value) {
  	  var type = typeof value;
  	  return (type == 'string' || type == 'number' || type == 'symbol' || type == 'boolean')
  	    ? (value !== '__proto__')
  	    : (value === null);
  	}
docs: Checks if `value` is suitable for use as unique object key.
  
  @private
  @param {*} value The value to check.
  @returns {boolean} Returns `true` if `value` is suitable, else `false`.