no property 'opCall' for type ... what am I doing wrong?

[Daniel Keep]

Frits van Bommel wrote:
> Daniel Keep wrote:
>>
>> Frits van Bommel wrote:
>>> Daniel Keep wrote:
>>>> Just keep in mind that you can't take the address of a function
>>>> argument, so if you do this inside a function, you have to make a copy
>>>> first.
>>> I'm surprised by this statement, and can't find a mention of it in the
>>> spec.
>>> Do you have a reference for it?
>>
>> I don't know if it's in the spec (I can't remember ever running across
>> it), but I know it doesn't work.
>>
>> The problem is that the D calling convention allows for up to one
>> argument to be passed using registers, which don't *have* an address, so
>> taking the address of them doesn't always make sense.
> 
> DMD automatically copies a register-argument to a local variable on the
> stack if the address is required. As does my GDC, it seems...
> 
>> In any case, I know the compiler has barfed every time I've tried to do
>> it...
> 
> It's always worked fine for me.
> 
> For instance, the following works, whether I'm using DMD or GDC:
> ---
> import std.stdio;
> 
> void bar(int* x) {
>         assert(*x == 42);
>         writefln("*%s = %s", x, *x);
> }
> 
> void foo(int x) {
>         bar(&x);
> }
> 
> void main() {
>         foo(42);
> }
> ---
> (DMD 1.014, GDC 0.23/amd64)

Weird; you're right.  It does work.  I *swear* it didn't used to, tho.
I remember having to work around the problem for a library I was writing
and being a bit annoyed at the time...

Oh well.

	-- Daniel

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{
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              // guaranteed to be random.
}

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