Use list cons operator (a :: b) as a function

Question

F# lets you turn operators into functions by surrounding them with ( ): for instance, (+) is of type int -> int -> int

Answer 1

Unfortunately, no, you can't. :: is not an operator, but a "symbolic keyword" according to the language grammar (see section 3.6 of the spec), as are :?> and a few others. The language doesn't seem completely consistent here, though, since there are a few symbolic keywords which can be treated as though they were operators (at least (*) and (<@ @>)).