16 lines
397 B
JavaScript
16 lines
397 B
JavaScript
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'use strict';
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var _require = require('../helpers/is'),
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isFunction = _require.isFunction;
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module.exports = function average(key) {
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if (key === undefined) {
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return this.sum() / this.items.length;
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}
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if (isFunction(key)) {
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return new this.constructor(this.items).sum(key) / this.items.length;
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}
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return new this.constructor(this.items).pluck(key).sum() / this.items.length;
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};
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