On Thursday, 11 July 2013 at 15:25:10 UTC, bearophile wrote:
This used to compile (probably dmd 2.060):
struct Foo {
immutable int y;
void bar(TF)(TF f) pure {
f(1);
}
void spam() pure {
bar((int x) => y);
}
}
void main() {}
But now it gives:
test.d(4): Error: pure function 'test.Foo.bar!(immutable(int)
delegate(int x) nothrow @safe).bar' cannot call impure delegate
'f'
test.d(7): Error: template instance
test.Foo.bar!(immutable(int) delegate(int x) nothrow @safe)
error instantiating
Is it a correct error?
Bye,
bearophile
My guess is that before 2.063 immutable int y was implicitly
static, but now it is per instance data which requires context
pointer which is deduced to be impure - that why compilation
fails (try placing static attribute). In other words, before
2.063 this was a function and now it is a delegate. And delegates
currently don't play well with constness/immutability.
