Most(ly dead) Influential Programming Languages(hillelwayne.com)

    if $you-are-hungry { make-a-sandwich() }

    make-a-sandwich() if $you-are-hungry;

    if you are hungry make a sandwich

    make a sandwich if you are hungry

    sub factorial ( UInt $n ){
      return 1 if $n == 0;
      return 1 if $n == 1;

      return $n * factorial($n - 1)
    }

    sub factorial ( UInt $_ ){
      return 1 when 0;
      return 1 when 1;

      return $_ * factorial($_ - 1)
    }

    sub factorial ( UInt $_ ){
      return 1 when 0|1;

      return $_ * factorial($_ - 1)
    }

    return one when [it is] zero or one

    > Alice: What result should we give the user?
    >
    > Bob: Return one when zero or one.  
    > Otherwise multiply it by …

    return 1 if $n == 0;
    return 1 if $n == 1;