beers.rs

pub fn verse(n: i32) -> String {
  if n > 2 {
    format!("{0} bottles of beer on the wall, {0} bottles of beer.\nTake one down and pass it around, {1} bottles of beer on the wall.\n", n, n - 1)
  } else if n == 2 {
    format!("2 bottles of beer on the wall, 2 bottles of beer.\nTake one down and pass it around, 1 bottle of beer on the wall.\n")
  } else if n == 1 {
    format!("1 bottle of beer on the wall, 1 bottle of beer.\nTake it down and pass it around, no more bottles of beer on the wall.\n")
  } else {
    format!("No more bottles of beer on the wall, no more bottles of beer.\nGo to the store and buy some more, 99 bottles of beer on the wall.\n")
  }
}

pub fn sing(start: i32, end: i32) -> String {
  let mut song = (end..start+1).rev().map(|i| verse(i)).map(|s| s + "\n").collect::<String>();
  if song.ends_with("\n\n") { song.pop(); }
  song
}