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Diffstat (limited to 'js/src/builtin/Iterator.js')
| -rw-r--r-- | js/src/builtin/Iterator.js | 941 |
1 files changed, 941 insertions, 0 deletions
diff --git a/js/src/builtin/Iterator.js b/js/src/builtin/Iterator.js new file mode 100644 index 0000000000..0cc6cebf18 --- /dev/null +++ b/js/src/builtin/Iterator.js @@ -0,0 +1,941 @@ +/* This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +function IteratorIdentity() { + return this; +} + +/* ECMA262 7.2.7 */ +function IteratorNext(iteratorRecord, value) { + // Steps 1-2. + var result = + ArgumentsLength() < 2 + ? callContentFunction(iteratorRecord.nextMethod, iteratorRecord.iterator) + : callContentFunction( + iteratorRecord.nextMethod, + iteratorRecord.iterator, + value + ); + // Step 3. + if (!IsObject(result)) { + ThrowTypeError(JSMSG_OBJECT_REQUIRED, result); + } + // Step 4. + return result; +} + +// https://tc39.es/ecma262/#sec-getiterator +function GetIterator(obj, isAsync, method) { + // Step 1. If hint is not present, set hint to sync. + // Step 2. If method is not present, then + if (!method) { + // Step 2.a. If hint is async, then + if (isAsync) { + // Step 2.a.i. Set method to ? GetMethod(obj, @@asyncIterator). + method = GetMethod(obj, GetBuiltinSymbol("asyncIterator")); + + // Step 2.a.ii. If method is undefined, then + if (!method) { + // Step 2.a.ii.1. Let syncMethod be ? GetMethod(obj, @@iterator). + var syncMethod = GetMethod(obj, GetBuiltinSymbol("iterator")); + + // Step 2.a.ii.2. Let syncIteratorRecord be ? GetIterator(obj, sync, syncMethod). + var syncIteratorRecord = GetIterator(obj, false, syncMethod); + + // Step 2.a.ii.2. Return CreateAsyncFromSyncIterator(syncIteratorRecord). + return CreateAsyncFromSyncIterator(syncIteratorRecord.iterator, syncIteratorRecord.nextMethod); + } + } else { + // Step 2.b. Otherwise, set method to ? GetMethod(obj, @@iterator). + method = GetMethod(obj, GetBuiltinSymbol("iterator")); + } + } + + // Step 3. Let iterator be ? Call(method, obj). + var iterator = callContentFunction(method, obj); + + // Step 4. If Type(iterator) is not Object, throw a TypeError exception. + if (!IsObject(iterator)) { + ThrowTypeError(JSMSG_NOT_ITERABLE, obj === null ? "null" : typeof obj); + } + + // Step 5. Let nextMethod be ? GetV(iterator, "next"). + var nextMethod = iterator.next; + + // Step 6. Let iteratorRecord be the Record { [[Iterator]]: iterator, [[NextMethod]]: nextMethod, [[Done]]: false }. + var iteratorRecord = { + __proto__: null, + iterator, + nextMethod, + done: false, + }; + + // Step 7. Return iteratorRecord. + return iteratorRecord; +} + +/** + * GetIteratorFlattenable ( obj, stringHandling ) + * + * https://tc39.es/proposal-iterator-helpers/#sec-getiteratorflattenable + */ +function GetIteratorFlattenable(obj, rejectStrings) { + assert(typeof rejectStrings === "boolean", "rejectStrings is a boolean"); + + // Step 1. + if (!IsObject(obj)) { + // Step 1.a. + if (rejectStrings || typeof obj !== "string") { + ThrowTypeError(JSMSG_OBJECT_REQUIRED, obj === null ? "null" : typeof obj); + } + } + + // Step 2. + var method = obj[GetBuiltinSymbol("iterator")]; + + // Steps 3-4. + var iterator; + if (IsNullOrUndefined(method)) { + iterator = obj; + } else { + iterator = callContentFunction(method, obj); + } + + // Step 5. + if (!IsObject(iterator)) { + ThrowTypeError(JSMSG_OBJECT_REQUIRED, iterator === null ? "null" : typeof iterator); + } + + // Step 6. (Caller must call GetIteratorDirect.) + return iterator; +} + +/** + * Iterator.from ( O ) + * + * https://tc39.es/proposal-iterator-helpers/#sec-iterator.from + */ +function IteratorFrom(O) { + // Step 1. (Inlined call to GetIteratorDirect.) + var iterator = GetIteratorFlattenable(O, /* rejectStrings= */ false); + var nextMethod = iterator.next; + + // Step 2. + // + // Calls |isPrototypeOf| instead of |instanceof| to avoid looking up the + // `@@hasInstance` property. + var hasInstance = callFunction( + std_Object_isPrototypeOf, + GetBuiltinPrototype("Iterator"), + iterator + ); + + // Step 3. + if (hasInstance) { + return iterator; + } + + // Step 4. + var wrapper = NewWrapForValidIterator(); + + // Step 5. + UnsafeSetReservedSlot( + wrapper, + WRAP_FOR_VALID_ITERATOR_ITERATOR_SLOT, + iterator + ); + UnsafeSetReservedSlot( + wrapper, + WRAP_FOR_VALID_ITERATOR_NEXT_METHOD_SLOT, + nextMethod + ); + + // Step 6. + return wrapper; +} + +/** + * %WrapForValidIteratorPrototype%.next ( ) + * + * https://tc39.es/proposal-iterator-helpers/#sec-wrapforvaliditeratorprototype.next + */ +function WrapForValidIteratorNext() { + // Steps 1-2. + var O = this; + if (!IsObject(O) || (O = GuardToWrapForValidIterator(O)) === null) { + return callFunction( + CallWrapForValidIteratorMethodIfWrapped, + this, + "WrapForValidIteratorNext" + ); + } + + // Step 3. + var iterator = UnsafeGetReservedSlot(O, WRAP_FOR_VALID_ITERATOR_ITERATOR_SLOT); + var nextMethod = UnsafeGetReservedSlot(O, WRAP_FOR_VALID_ITERATOR_NEXT_METHOD_SLOT); + + // Step 4. + return callContentFunction(nextMethod, iterator); +} + +/** + * %WrapForValidIteratorPrototype%.return ( ) + * + * https://tc39.es/proposal-iterator-helpers/#sec-wrapforvaliditeratorprototype.return + */ +function WrapForValidIteratorReturn() { + // Steps 1-2. + var O = this; + if (!IsObject(O) || (O = GuardToWrapForValidIterator(O)) === null) { + return callFunction( + CallWrapForValidIteratorMethodIfWrapped, + this, + "WrapForValidIteratorReturn" + ); + } + + // Step 3. + var iterator = UnsafeGetReservedSlot(O, WRAP_FOR_VALID_ITERATOR_ITERATOR_SLOT); + + // Step 4. + assert(IsObject(iterator), "iterator is an object"); + + // Step 5. + var returnMethod = iterator.return; + + // Step 6. + if (IsNullOrUndefined(returnMethod)) { + return { + value: undefined, + done: true, + }; + } + + // Step 7. + return callContentFunction(returnMethod, iterator); +} + +/** + * %IteratorHelperPrototype%.next ( ) + * + * https://tc39.es/proposal-iterator-helpers/#sec-%iteratorhelperprototype%.next + */ +function IteratorHelperNext() { + // Step 1. + var O = this; + if (!IsObject(O) || (O = GuardToIteratorHelper(O)) === null) { + return callFunction( + CallIteratorHelperMethodIfWrapped, + this, + "IteratorHelperNext" + ); + } + var generator = UnsafeGetReservedSlot(O, ITERATOR_HELPER_GENERATOR_SLOT); + return callFunction(GeneratorNext, generator, undefined); +} + +/** + * %IteratorHelperPrototype%.return ( ) + * + * https://tc39.es/proposal-iterator-helpers/#sec-%iteratorhelperprototype%.return + */ +function IteratorHelperReturn() { + // Step 1. + var O = this; + + // Step 2. + if (!IsObject(O) || (O = GuardToIteratorHelper(O)) === null) { + return callFunction( + CallIteratorHelperMethodIfWrapped, + this, + "IteratorHelperReturn" + ); + } + + // Step 3. (Implicit) + + // Steps 4-6. + var generator = UnsafeGetReservedSlot(O, ITERATOR_HELPER_GENERATOR_SLOT); + return callFunction(GeneratorReturn, generator, undefined); +} + +// Lazy %Iterator.prototype% methods +// +// In order to match the semantics of the built-in generator objects used in +// the proposal, we use a reserved slot on the IteratorHelper objects to store +// a regular generator that is called from the %IteratorHelper.prototype% +// methods. +// +// Each of the lazy methods is divided into a prelude and a body, with the +// eager prelude steps being contained in the corresponding IteratorX method +// and the lazy body steps inside the IteratorXGenerator generator functions. +// +// Each prelude method initializes and returns a new IteratorHelper object. +// As part of this initialization process, the appropriate generator function +// is called, followed by GeneratorNext being called on returned generator +// instance in order to move it to its first yield point. This is done so that +// if the `return` method is called on the IteratorHelper before `next` has been +// called, we can catch them in the try and use the finally block to close the +// underlying iterator. + +/** + * Iterator.prototype.map ( mapper ) + * + * https://tc39.es/proposal-iterator-helpers/#sec-iteratorprototype.map + */ +function IteratorMap(mapper) { + // Step 1. + var iterator = this; + + // Step 2. + if (!IsObject(iterator)) { + ThrowTypeError(JSMSG_OBJECT_REQUIRED, iterator === null ? "null" : typeof iterator); + } + + // Step 3. + if (!IsCallable(mapper)) { + ThrowTypeError(JSMSG_NOT_FUNCTION, DecompileArg(0, mapper)); + } + + // Step 4. (Inlined call to GetIteratorDirect.) + var nextMethod = iterator.next; + + // Steps 5-7. + var result = NewIteratorHelper(); + var generator = IteratorMapGenerator(iterator, nextMethod, mapper); + UnsafeSetReservedSlot( + result, + ITERATOR_HELPER_GENERATOR_SLOT, + generator + ); + + // Stop at the initial yield point. + callFunction(GeneratorNext, generator); + + // Step 8. + return result; +} + +/** + * Iterator.prototype.map ( mapper ) + * + * Abstract closure definition. + * + * https://tc39.es/proposal-iterator-helpers/#sec-iteratorprototype.map + */ +function* IteratorMapGenerator(iterator, nextMethod, mapper) { + var isReturnCompletion = true; + try { + // Initial yield point to handle closing the iterator before the for-of + // loop has been entered for the first time. + yield; + + // Not a Return completion when execution continues normally after |yield|. + isReturnCompletion = false; + } finally { + // Call IteratorClose on a Return completion. + if (isReturnCompletion) { + IteratorClose(iterator); + } + } + + // Step 5.a. + var counter = 0; + + // Step 5.b. + for (var value of allowContentIterWithNext(iterator, nextMethod)) { + // Steps 5.b.i-iii. (Implicit through for-of loop) + + // Step 5.b.iv. + var mapped = callContentFunction(mapper, undefined, value, counter); + + // Step 5.b.v. (Implicit through for-of loop) + + // Step 5.b.vi. + yield mapped; + + // Step 5.b.vii. (Implicit through for-of loop) + + // Step 5.b.viii. + counter += 1; + } +} + +/** + * Iterator.prototype.filter ( predicate ) + * + * https://tc39.es/proposal-iterator-helpers/#sec-iteratorprototype.filter + */ +function IteratorFilter(predicate) { + // Step 1. + var iterator = this; + + // Step 2. + if (!IsObject(iterator)) { + ThrowTypeError(JSMSG_OBJECT_REQUIRED, iterator === null ? "null" : typeof iterator); + } + + // Step 3. + if (!IsCallable(predicate)) { + ThrowTypeError(JSMSG_NOT_FUNCTION, DecompileArg(0, predicate)); + } + + // Step 4. (Inlined call to GetIteratorDirect.) + var nextMethod = iterator.next; + + // Steps 5-7. + var result = NewIteratorHelper(); + var generator = IteratorFilterGenerator(iterator, nextMethod, predicate); + UnsafeSetReservedSlot( + result, + ITERATOR_HELPER_GENERATOR_SLOT, + generator + ); + + // Stop at the initial yield point. + callFunction(GeneratorNext, generator); + + // Step 8. + return result; +} + +/** + * Iterator.prototype.filter ( predicate ) + * + * Abstract closure definition. + * + * https://tc39.es/proposal-iterator-helpers/#sec-iteratorprototype.filter + */ +function* IteratorFilterGenerator(iterator, nextMethod, predicate) { + var isReturnCompletion = true; + try { + // Initial yield point to handle closing the iterator before the for-of + // loop has been entered for the first time. + yield; + + // Not a Return completion when execution continues normally after |yield|. + isReturnCompletion = false; + } finally { + // Call IteratorClose on a Return completion. + if (isReturnCompletion) { + IteratorClose(iterator); + } + } + + // Step 5.a. + var counter = 0; + + // Step 5.b. + for (var value of allowContentIterWithNext(iterator, nextMethod)) { + // Steps 5.b.i-iii. (Implicit through for-of loop) + + // Step 5.b.iv. + var selected = callContentFunction(predicate, undefined, value, counter); + + // Step 5.b.v. (Implicit through for-of loop) + + // Step 5.b.vi. + if (selected) { + // Step 5.b.vi.1. + yield value; + + // Step 5.b.vi.2. (Implicit through for-of loop) + } + + // Step 5.b.vii. + counter += 1; + } +} + +/** + * Iterator.prototype.take ( limit ) + * + * https://tc39.es/proposal-iterator-helpers/#sec-iteratorprototype.take + */ +function IteratorTake(limit) { + // Step 1. + var iterator = this; + + // Step 2. + if (!IsObject(iterator)) { + ThrowTypeError(JSMSG_OBJECT_REQUIRED, iterator === null ? "null" : typeof iterator); + } + + // Steps 3-6. + var integerLimit = std_Math_trunc(limit); + if (!(integerLimit >= 0)) { + ThrowRangeError(JSMSG_NEGATIVE_LIMIT); + } + + // Step 7. (Inlined call to GetIteratorDirect.) + var nextMethod = iterator.next; + + // Steps 8-10. + var result = NewIteratorHelper(); + var generator = IteratorTakeGenerator(iterator, nextMethod, integerLimit); + UnsafeSetReservedSlot( + result, + ITERATOR_HELPER_GENERATOR_SLOT, + generator + ); + + // Stop at the initial yield point. + callFunction(GeneratorNext, generator); + + // Step 11. + return result; +} + +/** + * Iterator.prototype.take ( limit ) + * + * Abstract closure definition. + * + * https://tc39.es/proposal-iterator-helpers/#sec-iteratorprototype.take + */ +function* IteratorTakeGenerator(iterator, nextMethod, remaining) { + var isReturnCompletion = true; + try { + // Initial yield point to handle closing the iterator before the for-of + // loop has been entered for the first time. + yield; + + // Not a Return completion when execution continues normally after |yield|. + isReturnCompletion = false; + } finally { + // Call IteratorClose on a Return completion. + if (isReturnCompletion) { + IteratorClose(iterator); + } + } + + // Step 8.a. (Implicit) + + // Step 8.b.i. (Reordered before for-of loop entry) + if (remaining === 0) { + IteratorClose(iterator); + return; + } + + // Step 8.b. + for (var value of allowContentIterWithNext(iterator, nextMethod)) { + // Steps 8.b.iii-iv. (Implicit through for-of loop) + + // Step 8.b.v. + yield value; + + // Step 8.b.vi. (Implicit through for-of loop) + + // Steps 8.b.i-ii. (Reordered) + if (--remaining === 0) { + // |break| implicitly calls IteratorClose. + break; + } + } +} + +/** + * Iterator.prototype.drop ( limit ) + * + * https://tc39.es/proposal-iterator-helpers/#sec-iteratorprototype.drop + */ +function IteratorDrop(limit) { + // Step 1. + var iterator = this; + + // Step 2. + if (!IsObject(iterator)) { + ThrowTypeError(JSMSG_OBJECT_REQUIRED, iterator === null ? "null" : typeof iterator); + } + + // Steps 3-6. + var integerLimit = std_Math_trunc(limit); + if (!(integerLimit >= 0)) { + ThrowRangeError(JSMSG_NEGATIVE_LIMIT); + } + + // Step 7. (Inlined call to GetIteratorDirect.) + var nextMethod = iterator.next; + + // Steps 8-10. + var result = NewIteratorHelper(); + var generator = IteratorDropGenerator(iterator, nextMethod, integerLimit); + UnsafeSetReservedSlot( + result, + ITERATOR_HELPER_GENERATOR_SLOT, + generator + ); + + // Stop at the initial yield point. + callFunction(GeneratorNext, generator); + + // Step 11. + return result; +} + +/** + * Iterator.prototype.drop ( limit ) + * + * Abstract closure definition. + * + * https://tc39.es/proposal-iterator-helpers/#sec-iteratorprototype.drop + */ +function* IteratorDropGenerator(iterator, nextMethod, remaining) { + var isReturnCompletion = true; + try { + // Initial yield point to handle closing the iterator before the for-of + // loop has been entered for the first time. + yield; + + // Not a Return completion when execution continues normally after |yield|. + isReturnCompletion = false; + } finally { + // Call IteratorClose on a Return completion. + if (isReturnCompletion) { + IteratorClose(iterator); + } + } + + // Step 8.a. (Implicit) + + // Steps 8.b-c. + for (var value of allowContentIterWithNext(iterator, nextMethod)) { + // Step 8.b.i. + if (remaining-- <= 0) { + // Steps 8.b.ii-iii. (Implicit through for-of loop) + // Steps 8.c.i-ii. (Implicit through for-of loop) + + // Step 8.c.iii. + yield value; + + // Step 8.c.iv. (Implicit through for-of loop) + } + } +} + +/** + * Iterator.prototype.flatMap ( mapper ) + * + * https://tc39.es/proposal-iterator-helpers/#sec-iteratorprototype.flatmap + */ +function IteratorFlatMap(mapper) { + // Step 1. + var iterator = this; + + // Step 2. + if (!IsObject(iterator)) { + ThrowTypeError(JSMSG_OBJECT_REQUIRED, iterator === null ? "null" : typeof iterator); + } + + // Step 3. + if (!IsCallable(mapper)) { + ThrowTypeError(JSMSG_NOT_FUNCTION, DecompileArg(0, mapper)); + } + + // Step 4. (Inlined call to GetIteratorDirect.) + var nextMethod = iterator.next; + + // Steps 5-7. + var result = NewIteratorHelper(); + var generator = IteratorFlatMapGenerator(iterator, nextMethod, mapper); + UnsafeSetReservedSlot( + result, + ITERATOR_HELPER_GENERATOR_SLOT, + generator + ); + + // Stop at the initial yield point. + callFunction(GeneratorNext, generator); + + // Step 8. + return result; +} + +/** + * Iterator.prototype.flatMap ( mapper ) + * + * https://tc39.es/proposal-iterator-helpers/#sec-iteratorprototype.flatmap + */ +function* IteratorFlatMapGenerator(iterator, nextMethod, mapper) { + var isReturnCompletion = true; + try { + // Initial yield point to handle closing the iterator before the for-of + // loop has been entered for the first time. + yield; + + // Not a Return completion when execution continues normally after |yield|. + isReturnCompletion = false; + } finally { + // Call IteratorClose on a Return completion. + if (isReturnCompletion) { + IteratorClose(iterator); + } + } + + // Step 5.a. + var counter = 0; + + // Step 5.b. + for (var value of allowContentIterWithNext(iterator, nextMethod)) { + // Steps 5.b.i-iii. (Implicit through for-of loop) + + // Step 5.b.iv. + var mapped = callContentFunction(mapper, undefined, value, counter); + + // Step 5.b.v. (Implicit through for-of loop) + + // Steps 5.b.vi. + var innerIterator = GetIteratorFlattenable(mapped, /* rejectStrings= */ true); + var innerIteratorNextMethod = innerIterator.next; + + // Step 5.b.vii. (Implicit through for-of loop) + + // Steps 5.b.viii-ix. + for (var innerValue of allowContentIterWithNext(innerIterator, innerIteratorNextMethod)) { + // Steps 5.b.ix.1-3 and 5.b.ix.4.a-b. (Implicit through for-of loop) + + // Step 5.b.ix.4.c. + yield innerValue; + + // Step 5.b.ix.4.d. (Implicit through for-of loop) + } + + // Step 5.b.x. + counter += 1; + } +} + +/** + * Iterator.prototype.reduce ( reducer [ , initialValue ] ) + * + * https://tc39.es/proposal-iterator-helpers/#sec-iteratorprototype.reduce + */ +function IteratorReduce(reducer /*, initialValue*/) { + // Step 1. + var iterator = this; + + // Step 2. + if (!IsObject(iterator)) { + ThrowTypeError(JSMSG_OBJECT_REQUIRED, iterator === null ? "null" : typeof iterator); + } + + // Step 3. + if (!IsCallable(reducer)) { + ThrowTypeError(JSMSG_NOT_FUNCTION, DecompileArg(0, reducer)); + } + + // Step 4. (Inlined call to GetIteratorDirect.) + var nextMethod = iterator.next; + + // Steps 5-6. + var accumulator; + var counter; + if (ArgumentsLength() === 1) { + // Steps 5.a-d. (Moved below.) + counter = -1; + } else { + // Step 6.a. + accumulator = GetArgument(1); + + // Step 6.b. + counter = 0; + } + + // Step 7. + for (var value of allowContentIterWithNext(iterator, nextMethod)) { + if (counter < 0) { + // Step 5. (Reordered steps to compute initial accumulator.) + + // Step 5.c. + accumulator = value; + + // Step 5.d. + counter = 1; + } else { + // Steps 7.a-c and 7.e. (Implicit through for-of loop) + + // Steps 7.d and 7.f-g. + accumulator = callContentFunction(reducer, undefined, accumulator, value, counter++); + } + } + + // Step 5.b. + if (counter < 0) { + ThrowTypeError(JSMSG_EMPTY_ITERATOR_REDUCE); + } + + // Step 7.b. + return accumulator; +} + +/** + * Iterator.prototype.toArray ( ) + * + * https://tc39.es/proposal-iterator-helpers/#sec-iteratorprototype.toarray + */ +function IteratorToArray() { + // Step 1. + var iterator = this; + + // Step 2. + if (!IsObject(iterator)) { + ThrowTypeError(JSMSG_OBJECT_REQUIRED, iterator === null ? "null" : typeof iterator); + } + + // Step 3. (Inlined call to GetIteratorDirect.) + var nextMethod = iterator.next; + + // Steps 4-5. + return [...allowContentIterWithNext(iterator, nextMethod)]; +} + +/** + * Iterator.prototype.forEach ( fn ) + * + * https://tc39.es/proposal-iterator-helpers/#sec-iteratorprototype.foreach + */ +function IteratorForEach(fn) { + // Step 1. + var iterator = this; + + // Step 2. + if (!IsObject(iterator)) { + ThrowTypeError(JSMSG_OBJECT_REQUIRED, iterator === null ? "null" : typeof iterator); + } + + // Step 3. + if (!IsCallable(fn)) { + ThrowTypeError(JSMSG_NOT_FUNCTION, DecompileArg(0, fn)); + } + + // Step 4. (Inlined call to GetIteratorDirect.) + var nextMethod = iterator.next; + + // Step 5. + var counter = 0; + + // Step 6. + for (var value of allowContentIterWithNext(iterator, nextMethod)) { + // Steps 6.a-c. (Implicit through for-of loop) + + // Steps 6.d and 6.f. + callContentFunction(fn, undefined, value, counter++); + + // Step 6.e. (Implicit through for-of loop) + } +} + +/** + * Iterator.prototype.some ( predicate ) + * + * https://tc39.es/proposal-iterator-helpers/#sec-iteratorprototype.some + */ +function IteratorSome(predicate) { + // Step 1. + var iterator = this; + + // Step 2. + if (!IsObject(iterator)) { + ThrowTypeError(JSMSG_OBJECT_REQUIRED, iterator === null ? "null" : typeof iterator); + } + + // Step 3. + if (!IsCallable(predicate)) { + ThrowTypeError(JSMSG_NOT_FUNCTION, DecompileArg(0, predicate)); + } + + // Step 4. (Inlined call to GetIteratorDirect.) + var nextMethod = iterator.next; + + // Step 5. + var counter = 0; + + // Step 6. + for (var value of allowContentIterWithNext(iterator, nextMethod)) { + // Steps 6.a-c. (Implicit through for-of loop) + + // Steps 6.d-g. + if (callContentFunction(predicate, undefined, value, counter++)) { + return true; + } + } + + // Step 6.b. + return false; +} + +/** + * Iterator.prototype.every ( predicate ) + * + * https://tc39.es/proposal-iterator-helpers/#sec-iteratorprototype.every + */ +function IteratorEvery(predicate) { + // Step 1. + var iterator = this; + + // Step 2. + if (!IsObject(iterator)) { + ThrowTypeError(JSMSG_OBJECT_REQUIRED, iterator === null ? "null" : typeof iterator); + } + + // Step 3. + if (!IsCallable(predicate)) { + ThrowTypeError(JSMSG_NOT_FUNCTION, DecompileArg(0, predicate)); + } + + // Step 4. (Inlined call to GetIteratorDirect.) + var nextMethod = iterator.next; + + // Step 5. + var counter = 0; + + // Step 6. + for (var value of allowContentIterWithNext(iterator, nextMethod)) { + // Steps 6.a-c. (Implicit through for-of loop) + + // Steps 6.d-g. + if (!callContentFunction(predicate, undefined, value, counter++)) { + return false; + } + } + + // Step 6.b. + return true; +} + +/** + * Iterator.prototype.find ( predicate ) + * + * https://tc39.es/proposal-iterator-helpers/#sec-iteratorprototype.find + */ +function IteratorFind(predicate) { + // Step 1. + var iterator = this; + + // Step 2. + if (!IsObject(iterator)) { + ThrowTypeError(JSMSG_OBJECT_REQUIRED, iterator === null ? "null" : typeof iterator); + } + + // Step 3. + if (!IsCallable(predicate)) { + ThrowTypeError(JSMSG_NOT_FUNCTION, DecompileArg(0, predicate)); + } + + // Step 4. (Inlined call to GetIteratorDirect.) + var nextMethod = iterator.next; + + // Step 5. + var counter = 0; + + // Step 6. + for (var value of allowContentIterWithNext(iterator, nextMethod)) { + // Steps 6.a-c. (Implicit through for-of loop) + + // Steps 6.d-g. + if (callContentFunction(predicate, undefined, value, counter++)) { + return value; + } + } +} |