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- 'use strict';
- var $TypeError = require('es-errors/type');
- var Get = require('es-abstract/2024/Get');
- var GetValueFromBuffer = require('es-abstract/2024/GetValueFromBuffer');
- var IsDetachedBuffer = require('es-abstract/2024/IsDetachedBuffer');
- var max = require('math-intrinsics/max');
- var min = require('math-intrinsics/min');
- var Set = require('es-abstract/2024/Set');
- var SetValueInBuffer = require('es-abstract/2024/SetValueInBuffer');
- var ToIntegerOrInfinity = require('es-abstract/2024/ToIntegerOrInfinity');
- var ToString = require('es-abstract/2024/ToString');
- var TypedArrayElementSize = require('es-abstract/2024/TypedArrayElementSize');
- var TypedArrayElementType = require('es-abstract/2024/TypedArrayElementType');
- var TypedArraySpeciesCreate = require('es-abstract/2024/TypedArraySpeciesCreate');
- var ValidateTypedArray = require('es-abstract/2024/ValidateTypedArray');
- var typedArrayBuffer = require('typed-array-buffer');
- var typedArrayByteOffset = require('typed-array-byte-offset');
- // https://tc39.es/ecma262/#sec-%typedarray%.prototype.slice
- module.exports = function slice(start, end) {
- var O = this; // step 1
- ValidateTypedArray(O, 'SEQ-CST'); // step 2
- // 3. Let len be O.[[ArrayLength]].
- var len = O.length; // steps 3
- var relativeStart = ToIntegerOrInfinity(start); // step 4
- var k;
- if (relativeStart === -Infinity) {
- k = 0; // step 5
- } else if (relativeStart < 0) {
- k = max(len + relativeStart, 0); // step 6
- } else {
- k = min(relativeStart, len); // step 7
- }
- var relativeEnd = typeof end === 'undefined' ? len : ToIntegerOrInfinity(end); // step 8
- var final;
- if (relativeEnd === -Infinity) {
- final = 0; // step 9
- } else if (relativeEnd < 0) {
- final = max(len + relativeEnd, 0); // step 10
- } else {
- final = min(relativeEnd, len); // step 11
- }
- var count = max(final - k, 0); // step 12
- var A = TypedArraySpeciesCreate(O, [count]); // step 13
- if (count > 0) { // step 14
- if (IsDetachedBuffer(typedArrayBuffer(O))) {
- throw new $TypeError('Cannot use a Typed Array with an underlying ArrayBuffer that is detached'); // step 14.a
- }
- var srcType = TypedArrayElementType(O); // step 14.b
- var targetType = TypedArrayElementType(A); // step 14.c
- if (srcType === targetType) { // step 14.d
- // 1. NOTE: The transfer must be performed in a manner that preserves the bit-level encoding of the source data.
- var srcBuffer = typedArrayBuffer(O); // step 14.d.ii
- var targetBuffer = typedArrayBuffer(A); // step 14.d.iii
- var elementSize = TypedArrayElementSize(O); // step 14.d.iv
- var srcByteOffset = typedArrayByteOffset(O); // step 14.d.v
- var srcByteIndex = (k * elementSize) + srcByteOffset; // step 14.d.vi
- var targetByteIndex = typedArrayByteOffset(A); // step 14.d.vii
- var limit = targetByteIndex + (count * elementSize); // step 14.d.viii
- while (targetByteIndex < limit) { // step 14.d.ix
- var value = GetValueFromBuffer(srcBuffer, srcByteIndex, 'UINT8', true, 'UNORDERED'); // step 14.d.ix.1
- SetValueInBuffer(targetBuffer, targetByteIndex, 'UINT8', value, true, 'UNORDERED'); // step 14.d.ix.2
- srcByteIndex += 1; // step 14.d.ix.3
- targetByteIndex += 1; // step 14.d.ix.4
- }
- } else { // step 14.e
- var n = 0; // step 14.e.i
- while (k < final) { // step 14.e.ii
- var Pk = ToString(k); // step 14.e.ii.1
- var kValue = Get(O, Pk); // step 14.e.ii.2
- Set(A, ToString(n), kValue, true); // step 14.e.ii.3
- k += 1; // step 14.e.ii.4
- n += 1; // step 14.e.ii.5
- }
- }
- }
- return A; // step 15
- };
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