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41 lines
1.1 KiB
JavaScript
41 lines
1.1 KiB
JavaScript
6 years ago
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/** Error message constants. */
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var FUNC_ERROR_TEXT = 'Expected a function';
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/**
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* Creates a function that negates the result of the predicate `func`. The
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* `func` predicate is invoked with the `this` binding and arguments of the
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* created function.
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*
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* @static
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* @memberOf _
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* @since 3.0.0
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* @category Function
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* @param {Function} predicate The predicate to negate.
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* @returns {Function} Returns the new negated function.
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* @example
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*
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* function isEven(n) {
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* return n % 2 == 0;
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* }
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*
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* _.filter([1, 2, 3, 4, 5, 6], _.negate(isEven));
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* // => [1, 3, 5]
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*/
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function negate(predicate) {
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if (typeof predicate != 'function') {
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throw new TypeError(FUNC_ERROR_TEXT);
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}
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return function() {
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var args = arguments;
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switch (args.length) {
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case 0: return !predicate.call(this);
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case 1: return !predicate.call(this, args[0]);
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case 2: return !predicate.call(this, args[0], args[1]);
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case 3: return !predicate.call(this, args[0], args[1], args[2]);
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}
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return !predicate.apply(this, args);
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};
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}
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module.exports = negate;
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