Bug 12927 – Can't get at compile-time the immutable field of a struct instance in a TypeTuple

I am not fully sure this code is valid, but this used to work until recently: alias TypeTuple(T...) = T; struct Foo { int a; immutable int b; } struct Bar { auto foos = TypeTuple!(Foo(10, 20), Foo(10, 20)); void bar() { enum i = 1; enum r = foos[i].b; } } void main() {} With dmd 2.066alpha it gives: temp.d(10,18): Error: value of 'this' is not known at compile time I use this idiom to have struct instances with some mutable fields and with some "enum" fields.

In 2.063 and earlier, the code had been incorrectly accepted. Bar.foos is an instance field, so cannot evaluate it without valid 'this' expression.

(In reply to Kenji Hara from comment #1) > In 2.063 and earlier, the code had been incorrectly accepted. > > Bar.foos is an instance field, so cannot evaluate it without valid 'this' > expression. I see. And is it right to reject this too: alias TypeTuple(T...) = T; struct Foo { int a; immutable int b; } __gshared foos = TypeTuple!(Foo(10, 20), Foo(10, 20)); struct Bar { void bar() { enum i = 1; enum r = foos[i].b; } } void main() {} dmd 2.066alpha gives: test.d(6): Error: static variable _foos_field_1 cannot be read at compile time