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- 'use strict';
- var $SyntaxError = require('es-errors/syntax');
- var $TypeError = require('es-errors/type');
- var GetValueFromBuffer = require('./GetValueFromBuffer');
- var IsDetachedBuffer = require('./IsDetachedBuffer');
- var IsInteger = require('./IsInteger');
- var isNegativeZero = require('../helpers/isNegativeZero');
- var typedArrayLength = require('typed-array-length');
- var typedArrayBuffer = require('typed-array-buffer');
- var typedArrayByteOffset = require('typed-array-byte-offset');
- var whichTypedArray = require('which-typed-array');
- var tableTAO = require('./tables/typed-array-objects');
- // https://262.ecma-international.org/6.0/#sec-integerindexedelementget
- module.exports = function IntegerIndexedElementGet(O, index) {
- if (typeof index !== 'number') {
- throw new $TypeError('`index` must be a Number'); // step 1
- }
- var arrayTypeName = whichTypedArray(O); // step 10
- if (!arrayTypeName) {
- throw new $TypeError('`O` must be a TypedArray'); // step 2
- }
- if (arrayTypeName === 'BigInt64Array' || arrayTypeName === 'BigUint64Array') {
- throw new $SyntaxError('BigInt64Array and BigUint64Array do not exist until ES2020');
- }
- var buffer = typedArrayBuffer(O); // step 3
- if (IsDetachedBuffer(buffer)) {
- throw new $TypeError('`O` has a detached buffer'); // step 4
- }
- if (!IsInteger(index) || isNegativeZero(index)) {
- return void undefined; // steps 5 - 6
- }
- var length = typedArrayLength(O); // step 7
- if (index < 0 || index >= length) {
- return void undefined; // step 8
- }
- var offset = typedArrayByteOffset(O); // step 9
- var elementType = tableTAO.name['$' + arrayTypeName]; // step 13
- var elementSize = tableTAO.size['$' + elementType]; // step 11
- var indexedPosition = (index * elementSize) + offset; // step 12
- return GetValueFromBuffer(buffer, indexedPosition, elementType); // step 14
- };
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