| 1 | 'use strict';
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| 2 |
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| 3 | var $SyntaxError = require('es-errors/syntax');
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| 4 | var $TypeError = require('es-errors/type');
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| 5 |
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| 6 | var GetValueFromBuffer = require('./GetValueFromBuffer');
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| 7 | var IsDetachedBuffer = require('./IsDetachedBuffer');
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| 8 | var IsInteger = require('./IsInteger');
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| 9 |
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| 10 | var isNegativeZero = require('math-intrinsics/isNegativeZero');
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| 11 |
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| 12 | var typedArrayLength = require('typed-array-length');
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| 13 | var typedArrayBuffer = require('typed-array-buffer');
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| 14 | var typedArrayByteOffset = require('typed-array-byte-offset');
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| 15 | var whichTypedArray = require('which-typed-array');
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| 16 |
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| 17 | var tableTAO = require('./tables/typed-array-objects');
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| 18 |
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| 19 | // https://262.ecma-international.org/8.0/#sec-integerindexedelementget
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| 20 |
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| 21 | module.exports = function IntegerIndexedElementGet(O, index) {
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| 22 | if (typeof index !== 'number') {
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| 23 | throw new $TypeError('`index` must be a Number'); // step 1
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| 24 | }
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| 25 | var arrayTypeName = whichTypedArray(O); // step 10
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| 26 | if (!arrayTypeName) {
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| 27 | throw new $TypeError('`O` must be a TypedArray'); // step 2
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| 28 | }
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| 29 | if (arrayTypeName === 'BigInt64Array' || arrayTypeName === 'BigUint64Array') {
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| 30 | throw new $SyntaxError('BigInt64Array and BigUint64Array do not exist until ES2020');
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| 31 | }
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| 32 |
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| 33 | var buffer = typedArrayBuffer(O); // step 3
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| 34 |
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| 35 | if (IsDetachedBuffer(buffer)) {
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| 36 | throw new $TypeError('`O` has a detached buffer'); // step 4
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| 37 | }
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| 38 |
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| 39 | if (!IsInteger(index) || isNegativeZero(index)) {
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| 40 | return void undefined; // steps 5 - 6
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| 41 | }
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| 42 |
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| 43 | var length = typedArrayLength(O); // step 7
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| 44 |
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| 45 | if (index < 0 || index >= length) {
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| 46 | return void undefined; // step 8
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| 47 | }
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| 48 |
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| 49 | var offset = typedArrayByteOffset(O); // step 9
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| 50 |
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| 51 | var elementType = tableTAO.name['$' + arrayTypeName]; // step 13
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| 52 |
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| 53 | var elementSize = tableTAO.size['$' + elementType]; // step 11
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| 54 |
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| 55 | var indexedPosition = (index * elementSize) + offset; // step 12
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| 56 |
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| 57 | return GetValueFromBuffer(buffer, indexedPosition, elementType, true, 'Unordered'); // step 14
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| 58 | };
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