mirror of https://github.com/jkjoy/sunpeiwen.git
47 lines
1.3 KiB
JavaScript
47 lines
1.3 KiB
JavaScript
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'use strict';
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var GetIntrinsic = require('get-intrinsic');
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var $RangeError = GetIntrinsic('%RangeError%');
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var $TypeError = GetIntrinsic('%TypeError%');
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var callBound = require('call-bind/callBound');
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// node 0.10 doesn't have a prototype method
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var $byteOffset = callBound('TypedArray.prototype.byteOffset', true) || function (x) { return x.byteOffset; };
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var ToIndex = require('./ToIndex');
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var TypedArrayElementSize = require('./TypedArrayElementSize');
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var isTypedArray = require('is-typed-array');
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var typedArrayLength = require('typed-array-length');
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// https://262.ecma-international.org/13.0/#sec-validateatomicaccess
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module.exports = function ValidateAtomicAccess(typedArray, requestIndex) {
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if (!isTypedArray(typedArray)) {
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throw new $TypeError('Assertion failed: `typedArray` must be a TypedArray');
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}
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var length = typedArrayLength(typedArray); // step 1
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var accessIndex = ToIndex(requestIndex); // step 2
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/*
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// this assertion can never be reached
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if (!(accessIndex >= 0)) {
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throw new $TypeError('Assertion failed: accessIndex >= 0'); // step 4
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}
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*/
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if (accessIndex >= length) {
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throw new $RangeError('index out of range'); // step 4
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}
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var elementSize = TypedArrayElementSize(typedArray); // step 5
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var offset = $byteOffset(typedArray); // step 6
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return (accessIndex * elementSize) + offset; // step 7
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};
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