ALIAS()
 Return a specified work area alias
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 Syntax

     ALIAS([<nWorkArea>]) --> cAlias

 Arguments

     <nWorkArea> is any work area number.

 Returns

     ALIAS() returns the alias of the specified work area as a character
     string in uppercase.  If <nWorkArea> is not specified, the alias of the
     current work area is returned.  If there is no database file in USE for
     the specified work area, ALIAS() returns a null string ("").

 Description

     ALIAS() is a database function that determines the alias of a specified
     work area.  An alias is the name assigned to a work area when a database
     file is USEd.  The actual name assigned is either the name of the
     database file, or a name explicitly assigned with the ALIAS clause of
     the USE command.

     ALIAS() is the inverse of the SELECT() function.  ALIAS() returns the
     alias name given the work area number, and SELECT() returns the work
     area number given the alias name.

     .  This example returns the name of the previously selected work
        area:

        USE File1 NEW ALIAS Test1
        nOldArea := SELECT()
        USE File2 NEW ALIAS Test2
        ? ALIAS( nOldArea )            // Returns Test1

 Files   Library is CLIPPER.LIB.