Pattern matching with guards vs if/else construct in F#

Question

In ML-family languages, people tend to prefer pattern matching to if/else construct. In F#, using guards within pattern matching could easily replace if/e

Answer 1

The right answer is probably it depends, but I surmise, in most cases, the compiled representation is the same. As an example

let f b =
  match b with
  | true -> 1
  | false -> 0

and

let f b =
  if b then 1
  else 0

both translate to

public static int f(bool b)
{
    if (!b)
    {
        return 0;
    }
    return 1;
}

Given that, it's mostly a matter of style. Personally I prefer pattern matching because the cases are always aligned, making it more readable. Also, they're (arguably) easier to expand later to handle more cases. I consider pattern matching an evolution of if/then/else.

There is also no additional run-time cost for pattern matching, with or without guards.