Enable |> to create a function out of two.

That means, f |> g creates a function which, when applied, first
applies f to its arguments and then g to the result of f. This is very
useful to create functions for map/filter:

map(sin, map(cos, map(sqrt, [1 2 3])))
or
map((x)->sin(cos(sqrt(x))), [1 2 3])
become
map(sqrt |> cos |> sin, [1 2 3])
which is much more readable imo.

And for a real-world use:

map((fname)->float32(imread(fname)), image_filenames)
becomes
map(imread |> float32, image_filenames)