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#ifndefkeyword

Preprocessor conditional directive

Preprocessorkeyworddocumented

Syntax

#ifndef symbol
' Conditionally included statements
#endif

Description


Conditionally includes statements at compile time.

Statements within the #ifndef...#endif block are included if symbol is not defined and excluded (ignored) if symbol is defined.

#ifndef symbol is equivalent to #if Not defined(symbol)

Remarks

Differences from QB


  • New to FreeBASIC

See also


Example


#ifndef __MYFILE_BI__

#define __MYFILE_BI__

    ' Declarations 

#endif


Reference

  • Documented in KeyPgPpifndef.html