Bug 5980 – foreach element of a type tuple of string literals is not implicitly convertible to immutable(char)*

This worked in 2.052 but is failing to compile in the latest beta for 2.053. This is used by LuaD. struct A { int a; } void main() { foreach(field; __traits(allMembers, A)) { usefield(field); } } void usefield(const(char)* foo) { }

Oh and the error message: break.d(7): Error: cannot implicitly convert expression (field) of type const(im mutable(char)[]) to const(char)*

(In reply to comment #0) > This worked in 2.052 but is failing to compile in the latest beta for 2.053. > This is used by LuaD. > > struct A { > int a; > } > void main() { > foreach(field; __traits(allMembers, A)) > { > usefield(field); > } > > } > > void usefield(const(char)* foo) { > } Why not use 'usefield(field.ptr)'? I don't think implicitly converting an array to a pointer is expected.

Well I invasion the code being expanded to: void main() { usefield("a"); } Which is expected to implicitly convert to const(char)*

The conversion of a string literal to a immutable(char)* has been disallowed, and for arguably good reasons. You may want to use a.ptr instead.

Actually it's a problem in foreach-ing a TupleExp of StringExp, not __traits. I changed the title to reflect that. ------------------------------------- template TypeTuple(T...) { alias T TypeTuple; } void main() { alias TypeTuple!"1" T; usefield(T[0]); // ok foreach (j; T) usefield(j); // error on 2.053 } void usefield(const(char)* foo) { } ------------------------------------- (Still, I think it's better to use .ptr then relying on it the implicit string literal -> pointer conversion.)

(In reply to comment #4) > The conversion of a string literal to a immutable(char)* has been disallowed, > and for arguably good reasons. You may want to use a.ptr instead. Really? Jesse's example in comment #3 is still compilable.

I must be confused, sorry.

Fixed in 2.055 beta, probably the same as issue 6220.