I'm trying to make my own little debug_writefln which only prints when I set my DEBUGG to true.

void dWritefln(...){
   if(DEBUGG==true) writefln( ? );
}

What should I place there to make this work, or should I approuch this wholly differently?

Saaa wrote:
> I'm trying to make my own little debug_writefln which only prints when I set my DEBUGG to true.
> 
> void dWritefln(...){
>    if(DEBUGG==true) writefln( ? );
> }
> 
> What should I place there to make this work, or should I approuch this wholly differently? 
> 
> 

Easier if you turn it inside out.

debug(DEBUGG) {
   alias writefln dWritefln;
}
else {
   void dWritefln(...) {}
}

--bb

Thanks,

As I think that changing a variable is easier than changing the compiler line I went with:

const bool DEBUGG=false;

static if (DEBUGG == true) {
 alias writefln dWritefln;
}
else {
 void dWritefln(...) {}
}

Will dWritefln(..){} compile to 'nothing'?
I mean, will calling dWritefln when DEBUGG=false take no cpu tick (does the
compiler see that it does nothing)?


>
> Easier if you turn it inside out.
>
> debug(DEBUGG) {
>    alias writefln dWritefln;
> }
> else {
>    void dWritefln(...) {}
> }
>
> --bb

Saaa wrote:
> Thanks,
> 
> As I think that changing a variable is easier than changing the compiler line I went with:
> 
> const bool DEBUGG=false;
> 
> static if (DEBUGG == true) {
>  alias writefln dWritefln;
> }
> else {
>  void dWritefln(...) {}
> }

I think you can set debug versions inside a file too.  That way you can have the best of both worlds.  Turn it on from the command line, or by modifying the file.

debug = DEBUGG;

debug(DEBUGG) {
 alias writefln dWritefln;
}
else {
 void dWritefln(...) {}
}

... at least that works with 'version'.  Not sure if it works with debug too.  (If it doesn't I'll file a bug about the inconsistency with 'version'.)

> Will dWritefln(..){} compile to 'nothing'?
> I mean, will calling dWritefln when DEBUGG=false take no cpu tick (does the
> compiler see that it does nothing)?


Yes.  See thread entitled "debug()" over in digitalmars.D.
digitalmars.com digitalmars.D:66826
digitalmars.com digitalmars.D:66827

But that may only be with -inline.  Not sure what flags Jarrett used when he ran the test.

--bb

Seems to work, thanks.


> Saaa wrote:
>> Thanks,
>>
>> As I think that changing a variable is easier than changing the compiler line I went with:
>>
>> const bool DEBUGG=false;
>>
>> static if (DEBUGG == true) {
>>  alias writefln dWritefln;
>> }
>> else {
>>  void dWritefln(...) {}
>> }
>
> I think you can set debug versions inside a file too.  That way you can have the best of both worlds.  Turn it on from the command line, or by modifying the file.
>
> debug = DEBUGG;
>
> debug(DEBUGG) {
>  alias writefln dWritefln;
> }
> else {
>  void dWritefln(...) {}
> }
>
> ... at least that works with 'version'.  Not sure if it works with debug too.  (If it doesn't I'll file a bug about the inconsistency with 'version'.)
>
>> Will dWritefln(..){} compile to 'nothing'?
> > I mean, will calling dWritefln when DEBUGG=false take no cpu tick
> (does the
> > compiler see that it does nothing)?
>
>
> Yes.  See thread entitled "debug()" over in digitalmars.D.
> digitalmars.com digitalmars.D:66826
> digitalmars.com digitalmars.D:66827
>
> But that may only be with -inline.  Not sure what flags Jarrett used when he ran the test.
>
> --bb