How to convert array of strings to string in D?

I have got array of strings like:

string [] foo = ["zxc", "asd", "qwe"];

I need to create string from them. Like: "zxc", "asd", "qwe" (yes every elements need be quoted and separate with comma from another, but it should be string, but not array of strings.

How can I do it's in functional style?