Hi,

I have this unit, but when I compile it, I get this error:

Illegal unit name XXX_Parser. The unit is saved under dfm_rrparser.pas.

Second question:

Why not displayed $INFO directive in the message window (I have enabled -vi switch in command line)?

{$IFDEF FPC}
   {$MACRO ON}
   {$IFNDEF XXX_}
     {$DEFINE XXX_:=DFM_RR} // replace prefix
   {$ENDIF}
{$ENDIF}
{$INFO compiled with XXX_}
unit XXX_parser;
{$mode objfpc}{$H+}
interface
implementation
end.

Thanks

Roman

The unit name must always match the file name.
This is logical, because otherwise the compiler can never find it if a reference to the unit is made in a uses clause.

It shows it here:
home: >fpc tm.pp -vwi
Target OS: Linux for x86-64
Compiling tm.pp
User defined: compiled with XXX_
tm.pp(10,17) Error: Illegal unit name: XXX_parser
tm.pp(16,16) Fatal: There were 1 errors compiling module, stopping Fatal: Compilation aborted
Error: /usr/local/bin/ppcx64 returned an error exitcode

So probably a lazarus issue ?

Michael.

-vi switch in command line)?

Macros are only expanded on whole tokens (aka words). So XXX_ is expanded, but XXX_parser is not. It's the same with C preprocessors by the way.

Regards,
Sven

This is one of the limitation that we have against C preprocessor macros:
in C, you would be able to use
$define XXX_parser XXX_ ## parser
so that

  unit XXX_parser;

would work as you want,
but I don't think that we ever implemented an equivalent inside the Free Pascal compiler.
The other aspect is that, according to Michael's answer, the information message sent to output is not passed trough the preprocessor, because it still prints XXX_, and not DFM_RR. I would qualify this as a feature, not a bug, but others might disagree on that.
This is because the source is parsed by using readcomment method, which will never try to replace macros.

Pierre Muller

Dne 15.7.2015 v 11:47 Pierre Free Pascal napsal(a):

Thanks for your answer

Roman

Dne 15.7.2015 v 10:16 Michael Van Canneyt napsal(a):

I understand this. I thought that the compiler searches the unit by file name and unit name is stored inside the unit. Test if it is desired unit would be trivial - but I guess you're right - it would be pointless.

name and unit name is stored inside the unit. Test if it is desired unit would be trivial - but I guess you're right - it would be pointless.

There is a compiler parameter to disable that restriction (check the help output, I don't remember the parameter right now), but it's definitely less tested...

Regards,
Sven

-Un, but it is only meant for the system unit, it should not be used for other files.

Michael.