This compiles but, I get 'opCmp: Error: Access Violation'

Any thoughts?

class fred {
 char[] opAdd(fred a){ return "Hello"; }
}

int main(char[][] args)
{
 fred f = new fred();
 fred g = new fred();
 char[] s;

  s = g + f;

 printf("opCmp: %s", s ~ "\0" );
 return 0;
}

Scott Egan wrote:

>This compiles but, I get 'opCmp: Error: Access Violation'
>
>Any thoughts?
>
>class fred {
> char[] opAdd(fred a){ return "Hello"; }
>}
>
>int main(char[][] args)
>{
> fred f = new fred();
> fred g = new fred();
> char[] s;
>
>  s = g + f;
>
> printf("opCmp: %s", s ~ "\0" );
>  
>
printf("opCmp: %.*s", s ~ "\0" );

If of D arrays as a struct with a length at the front.

> return 0;
>}
>
>
>  
>


-- 
-Anderson: http://badmama.com.au/~anderson/

In article <c631su$20rf$1@digitaldaemon.com>, Scott Egan says...
>
>This compiles but, I get 'opCmp: Error: Access Violation'
>
>Any thoughts?
>
>class fred {
> char[] opAdd(fred a){ return "Hello"; }
>}
>
>int main(char[][] args)
>{
> fred f = new fred();
> fred g = new fred();
> char[] s;
>
>  s = g + f;
>
> printf("opCmp: %s", s ~ "\0" );

Try %.*s

> return 0;
>}
>
>

 printf("opCmp: %s", s ~ "\0" );

This should either be (as other have said)
 printf("opCmp: %.*s", s ~ "\0" );
or
 printf("opCmp: %s", (char*)(s ~ "\0") );

Ben Hinkle wrote:

> printf("opCmp: %s", s ~ "\0" );
>
>This should either be (as other have said)
> printf("opCmp: %.*s", s ~ "\0" );
>or
> printf("opCmp: %s", (char*)(s ~ "\0") );
>  
>
It would be cool if we could have a bot that automaticly directed these questions to the wiki <g>

ie it would search for two words, printf and %s, 97% of the time I reckon it would hit correct

(sorry for sending a personal email :( )

-- 
-Anderson: http://badmama.com.au/~anderson/

Ben Hinkle wrote:

> 
>  printf("opCmp: %s", s ~ "\0" );
> 
> This should either be (as other have said)
>  printf("opCmp: %.*s", s ~ "\0" );

Which makes the null terminator redundant.

>  printf("opCmp: %s", (char*)(s ~ "\0") );

Or

	printf("opCmp: %s", toStringz(s) );

Stewart.

-- 
My e-mail is valid but not my primary mailbox, aside from its being the unfortunate victim of intensive mail-bombing at the moment.  Please keep replies on the 'group where everyone may benefit.

Sorry,  I'll try not to be so stupid in the future (but I can't promise
anything).

"J Anderson" <REMOVEanderson@badmama.com.au> wrote in message news:c63314$22ci$1@digitaldaemon.com...
> Scott Egan wrote:
>
> >This compiles but, I get 'opCmp: Error: Access Violation'
> >
> >Any thoughts?
> >
> >class fred {
> > char[] opAdd(fred a){ return "Hello"; }
> >}
> >
> >int main(char[][] args)
> >{
> > fred f = new fred();
> > fred g = new fred();
> > char[] s;
> >
> >  s = g + f;
> >
> > printf("opCmp: %s", s ~ "\0" );
> >
> >
> printf("opCmp: %.*s", s ~ "\0" );
>
> If of D arrays as a struct with a length at the front.
>
> > return 0;
> >}
> >
> >
> >
> >
>
>
> -- 
> -Anderson: http://badmama.com.au/~anderson/

J Anderson schrieb:

> Scott Egan wrote:
> 
>> This compiles but, I get 'opCmp: Error: Access Violation'
>>
>> Any thoughts?
>>
>> class fred {
>> char[] opAdd(fred a){ return "Hello"; }
>> }

Always returns a constant array literal.

>> int main(char[][] args)
>> {
>> fred f = new fred();
>> fred g = new fred();
>> char[] s;
>>
>>  s = g + f;

From here s points to constant array literal.

>> printf("opCmp: %s", s ~ "\0" );
>>  
>>
> printf("opCmp: %.*s", s ~ "\0" );
> 
> If of D arrays as a struct with a length at the front.

doesn't matter here, since pointer is the first in the function parameter parsing queue. Maybe the error happens at concatenation - but why? I think only assembly level debugging would help here. Besides, try splitting away concatenation onto a separate line. Make a new variable, don't use =~ else you might loose the bug. Sorry that i can't be more helpful at the moment.

-eye

>>  printf("opCmp: %s", (char*)(s ~ "\0") );
>
>Or
>
>	printf("opCmp: %s", toStringz(s) );

oh yeah - it had been so long since I last toStringz'ed something I
had forgotten all about it. I'll take that as a good sign :-)
-Ben

J Anderson wrote:
> Ben Hinkle wrote:
> 
>> printf("opCmp: %s", s ~ "\0" );
>>
>> This should either be (as other have said)
>> printf("opCmp: %.*s", s ~ "\0" );
>> or
>> printf("opCmp: %s", (char*)(s ~ "\0") );
>>  
>>
> It would be cool if we could have a bot that automaticly directed these questions to the wiki <g>
> 
> ie it would search for two words, printf and %s, 97% of the time I reckon it would hit correct
> 
> (sorry for sending a personal email :( )

In the meantime, we could take turns manually directing them to: http://www.wikiservice.at/d/wiki.cgi?FaqRoadmap#RuntimeErrors
or
http://www.wikiservice.at/d/wiki.cgi?ErrorMessages

-- 
Justin
http://jcc_7.tripod.com/d/