IntegerIndexedElementSet.js 1.9 KB

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  1. 'use strict';
  2. var $SyntaxError = require('es-errors/syntax');
  3. var $TypeError = require('es-errors/type');
  4. var IsDetachedBuffer = require('./IsDetachedBuffer');
  5. var IsInteger = require('./IsInteger');
  6. var SetValueInBuffer = require('./SetValueInBuffer');
  7. var ToNumber = require('./ToNumber');
  8. var isNegativeZero = require('math-intrinsics/isNegativeZero');
  9. var typedArrayBuffer = require('typed-array-buffer');
  10. var typedArrayByteOffset = require('typed-array-byte-offset');
  11. var typedArrayLength = require('typed-array-length');
  12. var whichTypedArray = require('which-typed-array');
  13. var tableTAO = require('./tables/typed-array-objects');
  14. // https://262.ecma-international.org/6.0/#sec-integerindexedelementset
  15. module.exports = function IntegerIndexedElementSet(O, index, value) {
  16. if (typeof index !== 'number') {
  17. throw new $TypeError('`index` must be a Number'); // step 1
  18. }
  19. var arrayTypeName = whichTypedArray(O); // step 12
  20. if (!arrayTypeName) {
  21. throw new $TypeError('`O` must be a TypedArray'); // step 2
  22. }
  23. if (arrayTypeName === 'BigInt64Array' || arrayTypeName === 'BigUint64Array') {
  24. throw new $SyntaxError('BigInt64Array and BigUint64Array do not exist until ES2020'); // step 2
  25. }
  26. var numValue = ToNumber(value); // step 3
  27. var buffer = typedArrayBuffer(O); // step 5
  28. if (IsDetachedBuffer(buffer)) {
  29. throw new $TypeError('`O` has a detached buffer'); // step 6
  30. }
  31. if (!IsInteger(index) || isNegativeZero(index)) {
  32. return false; // steps 7 - 8
  33. }
  34. var length = typedArrayLength(O); // step 9
  35. if (index < 0 || index >= length) {
  36. return false; // step 10
  37. }
  38. var offset = typedArrayByteOffset(O); // step 11
  39. var elementType = tableTAO.name['$' + arrayTypeName]; // step 15
  40. var elementSize = tableTAO.size['$' + elementType]; // step 13
  41. var indexedPosition = (index * elementSize) + offset; // step 14
  42. SetValueInBuffer(buffer, indexedPosition, elementType, numValue); // step 16
  43. return true; // step 17
  44. };