https://issues.dlang.org/show_bug.cgi?id=21377
--- Comment #1 from [email protected] --- Relevant quote from the forums: "The actual problem is that the compiler isn't able to figure out the type of the lambda you've provided. If you change the argument to `(string str)`, it'll work. The real question is, why does type inference fail for the UDA when it works for the normal constructor call?" --
