Q3ValueStack Class

The Q3ValueStack class is a value-based template class that provides a stack. 更多...

头：	#include <Q3ValueStack>
继承：	Q3ValueList<T>

所有成员列表，包括继承成员

公共函数

	Q3ValueStack ()
	~Q3ValueStack ()
T	pop ()
void	push (const T & d )
T &	top ()
const T &	top () const

24 公共函数继承自 Q3ValueList
49 公共函数继承自 QLinkedList

额外继承成员

1 静态公共成员继承自 QLinkedList

详细描述

The Q3ValueStack class is a value-based template class that provides a stack.

Define a template instance Q3ValueStack <X> to create a stack of values that all have the class X.

注意， Q3ValueStack does not store pointers to the members of the stack; it holds a copy of every member. That is why these kinds of classes are called "value based"; Q3PtrStack , Q3PtrList , Q3Dict , etc., are "pointer based".

A stack is a last in, first out (LIFO) structure. Items are added to the top of the stack with push () and retrieved from the top with pop ()。 top () function provides access to the topmost item without removing it.

范例：

Q3ValueStack<int> stack;
stack.push( 1 );
stack.push( 2 );
stack.push( 3 );
while ( ! stack.isEmpty() )
    cout << "Item: " << stack.pop() << endl;
// Output:
//      Item: 3
//      Item: 2
//      Item: 1

Q3ValueStack is a specialized Q3ValueList provided for convenience. All of Q3ValueList 's functionality also applies to Q3PtrStack , for example the facility to iterate over all elements using Q3ValueStack <T>::Iterator. See Q3ValueListIterator 进一步了解细节。

Some classes cannot be used within a Q3ValueStack , for example everything derived from QObject and thus all classes that implement widgets. Only values can be used in a Q3ValueStack . To qualify as a value, the class must provide

a copy constructor;
an assignment operator;
a default constructor, i.e. a constructor that does not take any arguments.

Note that C++ defaults to field-by-field assignment operators and copy constructors if no explicit version is supplied. In many cases this is sufficient.

成员函数文档编制

Q3ValueStack:: Q3ValueStack ()

Constructs an empty stack.

Q3ValueStack:: ~Q3ValueStack ()

Destroys the stack. References to the values in the stack and all iterators of this stack become invalidated. Because Q3ValueStack is highly tuned for performance, you won't see warnings if you use invalid iterators because it is impossible for an iterator to check whether or not it is valid.

T Q3ValueStack:: pop ()

Removes the top item from the stack and returns it.

另请参阅 top () 和 push ().

void Q3ValueStack:: push (const T & d )

Adds element, d , to the top of the stack. Last in, first out.

此函数相当于 append ().

另请参阅 pop () 和 top ().

T & Q3ValueStack:: top ()

Returns a reference to the top item of the stack or the item referenced by end () if no such item exists. Note that you must not change the value the end () iterator points to.

此函数相当于 last ().

另请参阅 pop (), push ()，和 Q3ValueList::fromLast ().

const T & Q3ValueStack:: top () const

这是重载函数。

Returns a reference to the top item of the stack or the item referenced by end () if no such item exists.

此函数相当于 last ().

另请参阅 pop (), push ()，和 Q3ValueList::fromLast ().