Navigation:  Reference > Classes > TGXbStack()

The TGXbStack() class allow to implement sync/async stacks or queues and also can be used as a semaphore to serialize the access to the resources.

 

Class Methods:

::New( lSyncMode = .F. )

Create a new instance of the TGXbStack()class. If lSyncMode is .T. a critical section object will be used to serialize all method calls.

Instance Methods:

::Destroy() -> NIL

Release all allocated resources for this object. The ::Destroy() method need to be  explicitly called.

 

::Tos() -> uItem

Return the item at the Top Of Stack.

 

::Tail() -> uItem

Return the base of the stack.

 

::Pop() -> uItem

Remove the item at the Top Of Stack and return it.

 

::Push(<uItem>) -> nItemCount

Add a new item at the Top Of Stack

 

::Add(<uItem>) -> nItemCount

Add a New Item at the Stack Base

 

::Count() -> nItemCount

Return the number of items

 

::SEval(<bEval> , @<uCargo>) -> NIL

::SEval() -> aItems

Eval a codeblock {|uItem,uCargo| ... } for every item from the top to the base of the stack. If no parameters return an array with all the items in the same order.

 

::QEval(<bEval> , @<uCargo>) -> NIL

::QEval() -> aItems

Eval a codeblock {|uItem,uCargo| ... } for every item from the base to the top of the stack. If no parameters return an array with all the items in the same order.

 

::Lock() -> NIL

If the object was created with the SyncMode flag wait until own the critical section rights.

There are no internal counter for the ::Lock() / ::Unlock() operations so cannot be safe to use nested.

 

::UnLock()

Unlock the critical section rights.