lix-website/themes/lix/assets/bootstrap/node_modules/es-abstract/2019/IntegerIndexedElementGet.js

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2024-04-27 03:39:10 +00:00
'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/8.0/#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, true, 'Unordered'); // step 14
};