chris
746868d720
git-subtree-dir: main-site git-subtree-mainline: 4d1daa39101c0a85ca6d916f1c31139faf39632a git-subtree-split: 5cefb4d1618bc54ae0e86830421a8c911900302c
43 lines
911 B
JavaScript
43 lines
911 B
JavaScript
'use strict';
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const assert = require('assert');
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/**
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* Given a value, cast it to a number, or throw an `Error` if the value
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* cannot be casted. `null` and `undefined` are considered valid.
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*
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* @param {Any} value
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* @return {Number}
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* @throws {Error} if `value` is not one of the allowed values
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* @api private
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*/
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module.exports = function castNumber(val) {
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if (val == null) {
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return val;
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}
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if (val === '') {
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return null;
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}
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if (typeof val === 'string' || typeof val === 'boolean') {
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val = Number(val);
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}
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assert.ok(!isNaN(val));
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if (val instanceof Number) {
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return val.valueOf();
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}
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if (typeof val === 'number') {
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return val;
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}
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if (!Array.isArray(val) && typeof val.valueOf === 'function') {
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return Number(val.valueOf());
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}
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if (val.toString && !Array.isArray(val) && val.toString() == Number(val)) {
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return Number(val);
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}
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assert.ok(false);
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};
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