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authorFlorian Dold <florian.dold@gmail.com>2017-05-03 15:35:00 +0200
committerFlorian Dold <florian.dold@gmail.com>2017-05-03 15:35:00 +0200
commitde98e0b232509d5f40c135d540a70e415272ff85 (patch)
treea79222a5b58484ab3b80d18efcaaa7ccc4769b33 /node_modules/fbjs/lib/emptyFunction.js.flow
parente0c9d480a73fa629c1e4a47d3e721f1d2d345406 (diff)
node_modules
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diff --git a/node_modules/fbjs/lib/emptyFunction.js.flow b/node_modules/fbjs/lib/emptyFunction.js.flow
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+++ b/node_modules/fbjs/lib/emptyFunction.js.flow
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+/**
+ * Copyright (c) 2013-present, Facebook, Inc.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD-style license found in the
+ * LICENSE file in the root directory of this source tree. An additional grant
+ * of patent rights can be found in the PATENTS file in the same directory.
+ *
+ * @providesModule emptyFunction
+ * @flow
+ */
+
+function makeEmptyFunction<T>(arg: T): (...args: Array<any>) => T {
+ 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.
+ */
+const emptyFunction: (...args: Array<any>) => void = function () {};
+
+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; \ No newline at end of file