[fpc-pascal] Proper preprocessor?

[Sven Barth]

Am 22.06.2018 um 22:13 schrieb Florian Klämpfl:
> Am 22.06.2018 um 22:07 schrieb Sven Barth via fpc-pascal:
>> Am 22.06.2018 um 10:12 schrieb Ryan Joseph:
>>>
>>>> On Jun 22, 2018, at 12:24 PM, Sven Barth via fpc-pascal 
>>>> <fpc-pascal at lists.freepascal.org> wrote:
>>>>
>>>> If $Assertions is set to Off the complete Assert() line will be 
>>>> absent from the compiled code.
>>>
>>> Good to know thanks.
>>>
>>>
>>> Here’s an example of something I’ve seen for debugging. I think that 
>>> was kind of cool you could print types like that and I’m not sure 
>>> how that would work in Pascal if at all. Maybe some RTTI magic perhaps.
>>>
>>> {$define typestr(t):='#t: '+IntToStr(sizeof(#t))}
>>>
>>> program macro_test;
>>> uses
>>>     SysUtils;
>>>
>>> type
>>>     MyRecord = record
>>>         x, y, z: single;
>>>     end;
>>>
>>> begin
>>>     writeln(typestr(MyRecord)); // MyRecord: 12
>>> end.
>> In trunk that can be done rather nicely:
>>
>> === code begin ===
>>
>> program ttest;
>>
>> {$mode objfpc}
>>
>> uses
>>    TypInfo;
>>
>> type
>>    TMyRecord = record
>>      x, y, z: Single;
>>    end;
>>
>> generic function TypeStr<T>: String;
>> var
>>    ti: PTypeInfo;
>> begin
>>    ti := PTypeInfo(TypeInfo(T));
>>    WriteStr(Result, ti^.Name, ': ', SizeOf(T));
>> end;
>>
>> begin
>>    Writeln(specialize TypeStr<TMyRecord>);
>> end.
>>
>> === code end ===
>
> Or even
>
> program ttest;
>
> {$mode objfpc}
>
> uses
>   TypInfo;
>
> type
>   TMyRecord = record
>     x, y, z: Single;
>   end;
>
> generic function _TypeStr<T>: String;
> var
>   ti: PTypeInfo;
> begin
>   ti := PTypeInfo(TypeInfo(T));
>   WriteStr(Result, ti^.Name, ': ', SizeOf(T));
> end;
>
> {$macro on}
>
> {$define TypeStr:=specialize _TypeStr}
>
> begin
>   Writeln(TypeStr<TMyRecord>);
> end.
>
>
> ;) 
Those people can also use mode Delphi if they want :P

Regards,
Sven