Preprocessor directives

Simba 2.0 has much improved preprocessor directives allowing constant expressions and useful macros.

---

Basic expressions

{$DEFINE TEST}

const XYZ = 100;

begin
  {$IF XYZ = 100}
  WriteLn('XYZ = 100');
  {$ENDIF}

  {$IF XYZ*2+1 > 200}
  WriteLn('XYZ*2 > 200');
  {$ENDIF}

  {$IF DECLARED(XYZ) and DEFINED(TEST)}
  WriteLn('True');
  {$ELSE}
  WriteLn('False');
  {$ENDIF}

  {$UNDEF TEST}

  {$IF DECLARED(XYZ) and DEFINED(TEST)}
  WriteLn('True');
  {$ELSE}
  WriteLn('False');
  {$ENDIF}
end;

---

File

{$IF FILEEXISTS(Data\settings.ini)}
WriteLn('Settings file exists');
{$ELSE}
WriteLn('Settings file does not exist');
{$ENDIF}

---

Plugins

{$IF FINDLIB(libremoteinput)}
  {$loadlib libremoteinput}
{$ELSE}
  WriteLn('Cannot find libremoteinput!);
{$ENDIF}

{$IF LOADEDLIB(libremoteinput)}
  WriteLn('libremoteinput is loaded');
{$ELSE}
  WriteLn('libremoteinput is *not* loaded');
{$ENDIF}

---

Macros which are inserted constants at compile time.

procedure Test;
begin
  WriteLn('Func=', {$MACRO FUNC}); // current function name
end;

begin
  Test();
end;

begin
  WriteLn {$MACRO LINE}; // The line number
  WriteLn {$MACRO TICKCOUNT}; // GetTickCount
  WriteLn {$MACRO NOW}; // TDateTime.Now()
  WriteLn {$MACRO FILE}; // current file
  WriteLn {$MACRO DIR}; // directory the current file is in
  WriteLn {$MACRO ENV(USERPROFILE)}; // environment variable
  WriteLn {$MACRO INCLUDEDFILES}; // all included files (as a TStringArray)

  WriteLn {$MACRO LOADEDLIB(libremoteinput)}; // if lib "libremoteinput" is loaded, return the filename of the lib.
  WriteLn {$MACRO LOADEDLIBS}; // all loaded libs (as a TStringArray)
  WriteLn {$MACRO FINDLIB(libremoteinput)}; // try to find a lib, returning the path
end;