How can I create a partial function application for a non-symmetric operator such as the modulus operator with regards to the first argument without any argument names in F#? My first attempt was
let mod10 = (%) 10
which of course translates to
mod10(x) = 10 mod x
instead of the desired
mod10(x) = x mod 10
.
Certainly I could write
let mod10 x = (%)x 10
but I'd like to not have to name the argument so is there some placeholder that can be used, something like
let mod10 = (%)_ 10
?
You can define flip
function which is common in point-free style:
let inline flip f x y = f y x
and use it like this:
let (%-) = flip (%)
let mod10 = (%-) 10
or directly like this:
let mod10 = flip (%) 10
Point-free style is not always readable (as in this example) and not popular in F# programming.