emptyFunction.js 961 Bytes
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"use strict";

/**
 * Copyright (c) 2013-present, Facebook, Inc.
 *
 * This source code is licensed under the MIT license found in the
 * LICENSE file in the root directory of this source tree.
 *
 * 
 */
function makeEmptyFunction(arg) {
  return function () {
    return arg;
  };
}
/**
 * This function accepts and discards inputs; it has no side effects. This is
 * primarily useful idiomatically for overridable function endpoints which
 * always need to be callable, since JS lacks a null-call idiom ala Cocoa.
 */


var emptyFunction = function emptyFunction() {};

emptyFunction.thatReturns = makeEmptyFunction;
emptyFunction.thatReturnsFalse = makeEmptyFunction(false);
emptyFunction.thatReturnsTrue = makeEmptyFunction(true);
emptyFunction.thatReturnsNull = makeEmptyFunction(null);

emptyFunction.thatReturnsThis = function () {
  return this;
};

emptyFunction.thatReturnsArgument = function (arg) {
  return arg;
};

module.exports = emptyFunction;