On Sunday, 24 August 2014 at 18:55:09 UTC, ketmar via
Digitalmars-d-learn wrote:
On Sun, 24 Aug 2014 11:45:14 -0700
Ali Çehreli via Digitalmars-d-learn
<digitalmars-d-learn@puremagic.com>
wrote:
Yeah, the only reason why the original code does not work is
the
write() expression in the foreach body.
hm. really. i forgot what is delegate body for opApply. sure,
here we
can't use @nogc delegate. my fault.
Apologies for the misunderstanding. Before I close my enhancement
request I do have a followup question: is it possible somehow to
have both a @nogc and a normal opApply function available? My
code would like to have @nogc in as many places as possible, but
there will be places where I cannot make the foreach body @nogc
(I think; maybe some more Phobos functions can be annotated as
well and the problem would go away).
So I basically want something like this:
void bar() @nogc { }
void foreachBar() @nogc {
foreach (element; NumberRange(3, 7)) { bar(); }
}
void foo() { }
void foreachFoo() {
foreach (element; NumberRange(3, 7)) { foo(); }
}
void main() {
foreachBar();
foreachFoo();
}
Obviously if I have one opApply function one of the two functions
complains
opapply.d(36): Error: @nogc function 'opapply.foreachBar' cannot
call non-@nogc function 'opapply.NumberRange.opApply'
or
opapply.d(44): Error: function opapply.NumberRange.opApply (int
delegate(ref int) @nogc operations) const is not callable using
argument types (int delegate(ref int __applyArg0) @system)
If I add a second opApply function (one with @nogc, the other
without) the compiler cannot distinguish between the two:
opapply.d(36): Error: NumberRange(3, 7).opApply matches more than
one declaration:
opapply.d(5): const @nogc int(int delegate(ref int) @nogc
operations)
and:
opapply.d(18): const int(int delegate(ref int) operations)
opapply.d(36): Error: cannot uniquely infer foreach argument types
opapply.d(44): Error: NumberRange(3, 7).opApply matches more than
one declaration:
opapply.d(5): const @nogc int(int delegate(ref int) @nogc
operations)
and:
opapply.d(18): const int(int delegate(ref int) operations)
opapply.d(44): Error: cannot uniquely infer foreach argument types
Is this maybe something that could be used as an enhancement
request? Or I guess what I want is basically an 'inout' kind of
thing for @nogc...
