runtime/JSSetIterator.h

   1 /*
   2  * Copyright (C) 2013 Apple, Inc. All rights reserved.
   3  *
   4  * Redistribution and use in source and binary forms, with or without
   5  * modification, are permitted provided that the following conditions
   6  * are met:
   7  * 1. Redistributions of source code must retain the above copyright
   8  *    notice, this list of conditions and the following disclaimer.
   9  * 2. Redistributions in binary form must reproduce the above copyright
  10  *    notice, this list of conditions and the following disclaimer in the
  11  *    documentation and/or other materials provided with the distribution.
  12  *
  13  * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
  14  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  15  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  16  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
  17  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  18  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  19  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
  20  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
  21  * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  22  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  23  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  24  */
  25
  26 #ifndef JSSetIterator_h
  27 #define JSSetIterator_h
  28
  29 #include "JSDestructibleObject.h"
  30 #include "JSSet.h"
  31
  32 #include "MapData.h"
  33
  34 namespace JSC {
  35 enum SetIterationKind : uint32_t {
  36     SetIterateKey,
  37     SetIterateValue,
  38     SetIterateKeyValue,
  39 };
  40
  41 class JSSetIterator : public JSDestructibleObject {
  42 public:
  43     typedef JSDestructibleObject Base;
  44
  45     DECLARE_EXPORT_INFO;
  46
  47     static Structure* createStructure(VM& vm, JSGlobalObject* globalObject, JSValue prototype)
  48     {
  49         return Structure::create(vm, globalObject, prototype, TypeInfo(ObjectType, StructureFlags), info());
  50     }
  51
  52     static JSSetIterator* create(VM& vm, Structure* structure, JSSet* iteratedObject, SetIterationKind kind)
  53     {
  54         JSSetIterator* instance = new (NotNull, allocateCell<JSSetIterator>(vm.heap)) JSSetIterator(vm, structure, iteratedObject, kind);
  55         instance->finishCreation(vm, iteratedObject);
  56         return instance;
  57     }
  58
  59     bool next(CallFrame* callFrame, JSValue& value)
  60     {
  61         if (!m_iterator.ensureSlot())
  62             return false;
  63         if (m_kind == SetIterateValue || m_kind == SetIterateKey)
  64             value = m_iterator.key();
  65         else
  66             value = createPair(callFrame, m_iterator.key(), m_iterator.key());
  67         ++m_iterator;
  68         return true;
  69     }
  70
  71 private:
  72
  73     static const unsigned StructureFlags = Base::StructureFlags | OverridesVisitChildren;
  74
  75     JSSetIterator(VM& vm, Structure* structure, JSSet* iteratedObject, SetIterationKind kind)
  76         : Base(vm, structure)
  77         , m_iterator(iteratedObject->mapData()->begin())
  78         , m_kind(kind)
  79     {
  80     }
  81
  82     void finishCreation(VM&, JSSet*);
  83     JSValue createPair(CallFrame*, JSValue, JSValue);
  84     static void visitChildren(JSCell*, SlotVisitor&);
  85
  86     WriteBarrier<MapData> m_iteratedObjectData;
  87     MapData::const_iterator m_iterator;
  88     SetIterationKind m_kind;
  89 };
  90
  91 }
  92
  93 #endif // !defined(JSSetIterator_h)