Question if this kind of predicate is acceptable in extensions?

More of a question than a commit - Is this kind of predicate acceptable in the extensions? If so I'll complete them out. (Basically a wrapper in a sense on select<T>(Predicate) - It just made the code more self-documenting on my end)
Merge pull request #285 from MarkWalls/patch-2

Question if this kind of predicate is acceptable in extensions?