#undef

Preprocessor directive to undefine a macro

Syntax
   #undef symbol

Description
   Undefines a symbol previously defined with #define.

   Can be used to ensure that a macro or symbol has a limited lifespan and 
   does not conflict with a similar macro definition that may be defined 
   later in the source code.

   (Note: #undef should not be used to undefine variable or function names 
   used in the current function scope.  The names are needed internally by 
   the compiler and removing them can cause strange and unexpected 
   results.)

Example
   #define ADD2(a_, b_)  ((a_) + (b_))
   Print ADD2(1, 2)
   ' Macro no longer needed so get rid of it ...
   #undef ADD2

Differences from QB
   * New to Freebasic

See also
   * #define
   * #macro
   * #if
   * #else 
   * #elseif 
   * #endif 
   * #ifdef
   * #ifndef
   * defined

