%DEF operator

Purpose

Determine if an equate has been previously defined.

Syntax

%DEF({%numeric_equate | $string_equate})

Remarks

The %DEF operator tests whether or not an equate has been defined. If the equate has been defined, %DEF returns TRUE (non-zero); or FALSE (zero) if it has not be defined.

PowerBASIC automatically defines the equates in the following table according to the PowerBASIC compiler being used. Please note the references to other PowerBASIC compilers are included for those writing programs that may be compilable by more than one PowerBASIC compiler.

Equate	Definition
%PB_CC32	Pre-defined as TRUE (non-zero) in PB/CC for Windows, but is not defined in other compilers.
%PB_DLL16	Pre-defined as TRUE (non-zero) in PB/DLL 16-bit, but is not defined in other compilers.
%PB_DLL32	Synonym of %PB_WIN32
%PB_WIN32	Pre-defined as TRUE (non-zero) in PB/Win 32-bit, but is not defined in other compilers.
%PB_REVISION	Pre-defined as the hex revision (8.00 = &H800).
%PB_REVLETTER	Pre-defined as the ASCII code of the revision letter (a = &H61), or &H20 if there is no revision letter.
%PB_EXE	Pre-defined as TRUE (non-zero) if compiling to EXE or CON format (CON valid in PB/CC only), or as FALSE (zero) if compiling to DLL format (PB/Win only). The equate %PB_EXE is always defined in PowerBASIC, so %DEF(%PB_EXE) will always be evaluated as TRUE. The difference being the value assigned to the equate by the compiler. See the examples below.

These can be used in conjunction with #IF as a compiler directive to selectively include or exclude code from the compiled file.