This is a neat one. In my current project, I created a (non-lazy) pipe function that take a value and a bunch of functions, composes the functions, and applies the value.

pipe(2, add(2), square, n => n + 7) // -> 23

Nothing fancy but comes in handy at times.

What I really miss is something like the |> from Elixir. Maybe it's the same as F#, I don't know, but it automatically performs partial application, so that:

Enum.filter([1, 2, 3, 4], fn n -> n % 2 == 0 end)

also works like:

[1, 2, 3, 4] |> Enum.filter(fn n -> n % 2 == 0 end)