Bug 19257 – std.array.join does not handle const fields that cannot be converted to mutable

std.array.join tries to remove constness from its arrays' fields on the premise that it's constructing a new array anyways. However, consider const(Object)[][].join: const(Object) cannot be implicitly converted to Object, so the join fails. In that case, join should just return a const(Object)[] array.

See https://github.com/dlang/phobos/pull/6711

Commits pushed to master at https://github.com/dlang/phobos https://github.com/dlang/phobos/commit/7a32298747de7e0b302d39f8c836eef84a9b9e8c Fix issue 19257: Only remove const on .join if you can actually assign const to non-const values. https://github.com/dlang/phobos/commit/0994f692e2f6c1a32249d2153778083d4bc3d947 Merge pull request #6711 from FeepingCreature/fix/join-unassignable-const-arrays Fix issue 19257: std.array.join: only remove const if you can actually assign const to non-const values merged-on-behalf-of: Nathan Sashihara <[email protected]>