mirror of https://github.com/jkjoy/sunpeiwen.git
20 lines
515 B
JavaScript
20 lines
515 B
JavaScript
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'use strict';
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var ToNumber = require('./ToNumber');
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var floor = require('./floor');
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var $isNaN = require('../helpers/isNaN');
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// https://262.ecma-international.org/6.0/#sec-touint8clamp
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module.exports = function ToUint8Clamp(argument) {
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var number = ToNumber(argument);
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if ($isNaN(number) || number <= 0) { return 0; }
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if (number >= 0xFF) { return 0xFF; }
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var f = floor(number);
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if (f + 0.5 < number) { return f + 1; }
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if (number < f + 0.5) { return f; }
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if (f % 2 !== 0) { return f + 1; }
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return f;
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};
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