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import std.stdio;
enum Qwert { Yuiop, Asdfg }
void main() {
writefln(Qwert.Yuiop);
}
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Error: std.format formatArg
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The same happens with either
writefln("%s", Qwert.Yuiop);
or
writefln("%d", Qwert.Yuiop);
It may be the case that formatting of enums isn't yet implemented. But would it do any harm to have it just write out the numerical value for the meantime? In particular, there's no reason that the %d format shouldn't already work on them.