[saagarjha]

This doesn't work for me:

  $ swift
  Welcome to Apple Swift version 4.2.1 (swiftlang-1000.11.42 clang-1000.11.45.1). Type :help for assistance.
    1> let x = 3
  x: Int = 3
    2> if x in 2...4 {}
  error: repl.swift:2:6: error: expected '{' after 'if' condition
  if x in 2...4 {}
       ^

Are you sure you didn't mean to use if case?

  if case 2...4 = x

[zapzupnz]

Yeah, I was wrong. I updated my comment. I think I just meant to check if a range contains a value, as I changed it to.

[saagarjha]

You can use ~= if you're looking for a succinct way to do an operation like this:

  if 2...4 ~= x

[zapzupnz]

I didn't know about this. Brilliant, cheers!