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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
* 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/. */
#ifndef vm_StringObject_h
#define vm_StringObject_h
#include "jsobj.h"
#include "jsstr.h"
#include "vm/Shape.h"
namespace js {
class StringObject : public NativeObject
{
static const unsigned PRIMITIVE_VALUE_SLOT = 0;
static const unsigned LENGTH_SLOT = 1;
public:
static const unsigned RESERVED_SLOTS = 2;
static const Class class_;
/*
* Creates a new String object boxing the given string. The object's
* [[Prototype]] is determined from context.
*/
static inline StringObject* create(JSContext* cx, HandleString str,
HandleObject proto = nullptr,
NewObjectKind newKind = GenericObject);
/*
* Compute the initial shape to associate with fresh String objects, which
* encodes the initial length property. Return the shape after changing
* |obj|'s last property to it.
*/
static Shape*
assignInitialShape(ExclusiveContext* cx, Handle<StringObject*> obj);
JSString* unbox() const {
return getFixedSlot(PRIMITIVE_VALUE_SLOT).toString();
}
inline size_t length() const {
return size_t(getFixedSlot(LENGTH_SLOT).toInt32());
}
static size_t offsetOfPrimitiveValue() {
return getFixedSlotOffset(PRIMITIVE_VALUE_SLOT);
}
static size_t offsetOfLength() {
return getFixedSlotOffset(LENGTH_SLOT);
}
private:
static inline bool init(JSContext* cx, Handle<StringObject*> obj, HandleString str);
void setStringThis(JSString* str) {
MOZ_ASSERT(getReservedSlot(PRIMITIVE_VALUE_SLOT).isUndefined());
setFixedSlot(PRIMITIVE_VALUE_SLOT, StringValue(str));
setFixedSlot(LENGTH_SLOT, Int32Value(int32_t(str->length())));
}
/* For access to init, as String.prototype is special. */
friend JSObject*
js::InitStringClass(JSContext* cx, HandleObject global);
};
} // namespace js
#endif /* vm_StringObject_h */
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