time-to-botec

Benchmark sampling in different programming languages
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unionBy.js (1320B)

      1 var baseFlatten = require('./_baseFlatten'),
      2     baseIteratee = require('./_baseIteratee'),
      3     baseRest = require('./_baseRest'),
      4     baseUniq = require('./_baseUniq'),
      5     isArrayLikeObject = require('./isArrayLikeObject'),
      6     last = require('./last');
      7 
      8 /**
      9  * This method is like `_.union` except that it accepts `iteratee` which is
     10  * invoked for each element of each `arrays` to generate the criterion by
     11  * which uniqueness is computed. Result values are chosen from the first
     12  * array in which the value occurs. The iteratee is invoked with one argument:
     13  * (value).
     14  *
     15  * @static
     16  * @memberOf _
     17  * @since 4.0.0
     18  * @category Array
     19  * @param {...Array} [arrays] The arrays to inspect.
     20  * @param {Function} [iteratee=_.identity] The iteratee invoked per element.
     21  * @returns {Array} Returns the new array of combined values.
     22  * @example
     23  *
     24  * _.unionBy([2.1], [1.2, 2.3], Math.floor);
     25  * // => [2.1, 1.2]
     26  *
     27  * // The `_.property` iteratee shorthand.
     28  * _.unionBy([{ 'x': 1 }], [{ 'x': 2 }, { 'x': 1 }], 'x');
     29  * // => [{ 'x': 1 }, { 'x': 2 }]
     30  */
     31 var unionBy = baseRest(function(arrays) {
     32   var iteratee = last(arrays);
     33   if (isArrayLikeObject(iteratee)) {
     34     iteratee = undefined;
     35   }
     36   return baseUniq(baseFlatten(arrays, 1, isArrayLikeObject, true), baseIteratee(iteratee, 2));
     37 });
     38 
     39 module.exports = unionBy;