missing 'first' pipe

[nirsalon]

I'm submitting a ... (check one with "x")

[ ] bug report => search github for a similar issue or PR before submitting
[X] feature request

Current behavior
No pipe returns the first element that matches a condition

Expected behavior
A new pipe, similar to 'where', that returns the first element that matches the condition
See .NET linq .First() https://msdn.microsoft.com/en-us/library/bb535050(v=vs.110).aspx

What is the motivation / use case for changing the behavior?
A more performant pipe than (arr | where:[cond])[0]

[fknop]

That's a good idea, what about the firstWhere name ?

[nirsalon]

C# uses First(), and FirstOrDefault() which doesn't throw if not found
Java 8 uses findFirst()
Usually function names are either verb or 'verbNoun', so I'd say something like first/firstMatch/findFirst, but firstWhere also work.

[fknop]

I think I'll go with firstOrDefault.

I'll probably implement that with #40 tonight or tomorrow.