Collectors.joining()

With the CharSequence->String transformation, there is an overloaded version of Collectors.joining() that accepts a String, and another that accepts three Strings. Perfect!

Sadly, these methods return Collector<CharSequence> instead of Collector<String>, forcing me to write:

    value fileName = fileNameParts.stream()
            .filter(not(String.empty))
            .map(javaString)
            .collect(Collectors.joining("_"))
            .string;

Instead of just

    value fileName = fileNameParts.stream()
            .filter(not(String.empty))
            .collect(Collectors.joining("_"));

I say we do some special-casing here, so that I get back a Collector<String> for Collectors.joining(). WDYT, @FroMage?

[gavinking]

Yeah, but that wouldn’t be as cool.

[gavinking]

A very similar request, from @MikhailMalyutin, would be to make Java Comparators transform to Comparison(T,T) instead of Integer(T,T). That’s pretty reasonable, i suppose. Another special case…