Hi everyone,

I caught quite a bizarre bug on dmd v0.162 : if I use a foreach to iterate through an aggreate class instance in a litteral delegate between brackets, like this :

=====================================================

// some container
class Container {
int opApply (int delegate (inout int) dg) {
int i;
dg(i);
return 0;
}
}

void main () {
// a is assigned a delegate specified by a litteral
auto a = ( {
foreach (i ; new Container)
writefln(i);
});
}

=====================================================

the compiler crashes saying : Assertion failure: 'type || init' on line 440 in file 'declaration.c'

abnormal program termination

But if I make one of two possible changes, it compiles and runs without problem. First, if I want to iterate through a static or a dynamic array (an associative array won't work, though), it compiles and run perfectly.  Here's an example :

=====================================================

void main () {
int[] b;
// a is assigned a delegate specified by a litteral
auto a = ( {
foreach (i ; b)
writefln(i);
});
}

=====================================================

A perfect work around (in appearance at least, I just spent three hours on that problem so I don't pretend to have tested everything) is to tell the compiler explicitly that the expression in the right side of the assignment is a delegate, like this :

=====================================================

// some container
class Container {
int opApply (int delegate (inout int) dg) {
int i;
dg(i);
return 0;
}
}

void main () {
// a is assigned a delegate specified by a litteral
auto a = ( delegate int(){
foreach (i ; b)
writefln(i);
} );
}

=====================================================

It seems that this is not a really bad bug since you can get the work done simply by adding the type of the delegate, but I think the syntax without those keywords should work whatever is in the delegate.

Thanks for your attention.

Cheers

Simon Hudon

simon hudon schrieb am 2006-07-17:
> Hi everyone,
>
> I caught quite a bizarre bug on dmd v0.162 : if I use a foreach to iterate through an aggreate class instance in a litteral delegate between brackets, like this :
>
>=====================================================
>
> // some container
> class Container {
> int opApply (int delegate (inout int) dg) {
> int i;
> dg(i);
> return 0;
> }
> }
>
> void main () {
> // a is assigned a delegate specified by a litteral
> auto a = ( {
> foreach (i ; new Container)
> writefln(i);
> });
> }
>
>=====================================================
>
> the compiler crashes saying : Assertion failure: 'type || init' on line 440 in file 'declaration.c'
>
> abnormal program termination
>
> But if I make one of two possible changes, it compiles and runs without problem. First, if I want to iterate through a static or a dynamic array (an associative array won't work, though), it compiles and run perfectly.  Here's an example :
>
>=====================================================
>
> void main () {
> int[] b;
> // a is assigned a delegate specified by a litteral
> auto a = ( {
> foreach (i ; b)
> writefln(i);
> });
> }
>
>=====================================================
>
> A perfect work around (in appearance at least, I just spent three hours on that problem so I don't pretend to have tested everything) is to tell the compiler explicitly that the expression in the right side of the assignment is a delegate, like this :
>
>=====================================================
>
> // some container
> class Container {
> int opApply (int delegate (inout int) dg) {
> int i;
> dg(i);
> return 0;
> }
> }
>
> void main () {
> // a is assigned a delegate specified by a litteral
> auto a = ( delegate int(){
> foreach (i ; b)
> writefln(i);
> } );
> }
>
>=====================================================
>
> It seems that this is not a really bad bug since you can get the work done simply by adding the type of the delegate, but I think the syntax without those keywords should work whatever is in the delegate.
>
> Thanks for your attention.
>
> Cheers
>
> Simon Hudon

Added to DStress as http://dstress.kuehne.cn/b/bug_declaration_440_A.d http://dstress.kuehne.cn/b/bug_declaration_440_B.d http://dstress.kuehne.cn/b/bug_declaration_440_C.d

Thomas