mirror of
https://github.com/LadybirdBrowser/ladybird.git
synced 2025-12-08 06:09:58 +00:00
646457099c
With this change, `GetIterator` no longer GC-allocates an
`IteratorRecord`. Instead, it stores the iterator record fields in
bytecode registers. This avoids per-iteration allocations in patterns
like: `for (let [x] of array) {}`.
`IteratorRecord` now inherits from `IteratorRecordImpl`, which holds the
iteration state. This allows the existing iteration helpers
(`iterator_next()`, `iterator_step()`, etc.) operate on both the
GC-allocated and the register-backed forms.
Microbenchmarks:
1.1x array-destructuring-assignment-rest.js
1.226x array-destructuring-assignment.js
39 lines
923 B
C++
39 lines
923 B
C++
/*
|
|
* Copyright (c) 2020, Matthew Olsson <mattco@serenityos.org>
|
|
*
|
|
* SPDX-License-Identifier: BSD-2-Clause
|
|
*/
|
|
|
|
#pragma once
|
|
|
|
#include <AK/String.h>
|
|
#include <AK/Utf8View.h>
|
|
#include <LibJS/Runtime/Iterator.h>
|
|
#include <LibJS/Runtime/Object.h>
|
|
|
|
namespace JS {
|
|
|
|
class StringIterator final : public Object
|
|
, public BuiltinIterator {
|
|
JS_OBJECT(StringIterator, Object);
|
|
GC_DECLARE_ALLOCATOR(StringIterator);
|
|
|
|
public:
|
|
static GC::Ref<StringIterator> create(Realm&, String string);
|
|
|
|
virtual ~StringIterator() override = default;
|
|
|
|
BuiltinIterator* as_builtin_iterator_if_next_is_not_redefined(Value next_method) override;
|
|
ThrowCompletionOr<void> next(VM&, bool& done, Value& value) override;
|
|
|
|
private:
|
|
explicit StringIterator(String string, Object& prototype);
|
|
|
|
friend class StringIteratorPrototype;
|
|
|
|
String m_string;
|
|
Utf8CodePointIterator m_iterator;
|
|
bool m_done { false };
|
|
};
|
|
|
|
}
|