WinName A
string literal (without quotes) representing the name of a window,
or an at-sign followed by the name of a local variable (@name)
where the value of that variable is expected to be equal to the
name of a window at run-time.
If missing, the default is the current window.
Variable The name of a local or global array containing a definition of the window or control in MWAPI format.
The macro %%MergeWin causes the execution of a low-level command for creating a window at run-time from a definition in MWAPI format.