join

[so]

> 2. joiner uses an idiom that I've experimented with in the past: it  
> defines a local struct and returns it. As such, joiner's type is  
> impossible to express without auto. I find that idiom interesting for  
> many reasons, among which the simplest is that the code is terse,  
> compact, and doesn't pollute the namespace. I'm thinking we should do  
> the same for Appender - it doesn't make much sense to create an Appender  
> except by calling the appender() function.

Didn't know there was a solution to namespace pollution.
This one is a very nice idea, are you planning to use it in phobos in  
general?
Retro, Stride... there should be many.