Bug 17187 – Error when using std.format.unformatValue with static arrays

auto str = "aaa"; auto spec = singleSpec("%s"); assert(str.unformatValue!(char[3])(spec) == ['a', 'a', 'a']); std/conv.d(3877): Error: cannot implicitly convert expression (front(s)) of type dchar to char std/conv.d(3881): Error: cannot implicitly convert expression (parseEscape(s)) of type dchar to char std/format.d(4961): Error: template instance std.conv.parseElement!(char, string) error instantiating std/format.d(4889): instantiated from here: unformatElement!(char, string, char) std/format.d(4646): instantiated from here: unformatRange!(char[3], string, char) std/format.d(4798): instantiated from here: unformatValue!(char[3], string, char) std/range/primitives.d(347): Error: static assert "Cannot put a dchar into a char[]." std/format.d(4668): instantiated from here: put!(char[], dchar) std/format.d(4798): instantiated from here: unformatValue!(char[3], string, char)

BTW this is a bug because this works auto str = "aaa"; auto spec = singleSpec("%s"); dchar[3] ret = ['a', 'a', 'a']; assert(str.unformatValue!(dchar[3])(spec) == ret);

I don't think this is a valid bug. In the second example you are converting from dchar to dchar while in the first you are converting from dchar to char. -- Imagine, the string contains three chinese symbols instead of `a`s. They never fit into char[3].