My solution for generating the lyrics for the song "99 bottles on the wall" written in TypeScript.

99-bottles.ts

const capitalize = (word: string) => word[0].toUpperCase() + word.substr(1);

const pluralize = (word: string, amount: number) => {
  if (amount > 1) return `${amount} ${word}s`;
  if (amount === 1) return `${amount} ${word}`;
  return `no more ${word}s`;
};

const countBottles = (amount: number) =>
  `${pluralize("bottle", amount)} of beer`;

const lyricsForVerse = (i: number, numVerses: number) => {
  const numBottles = numVerses - i;
  return numBottles === 0
    ? [
      `${countBottles(numBottles)} on the wall, ${countBottles(numBottles)}.`,
      `go to the store and buy some more,`,
      `${countBottles(numVerses)}...`,
    ]
    : [
      `${countBottles(numBottles)} on the wall, ${countBottles(numBottles)}.`,
      `take ${numBottles > 1 ? "one" : "it"} down, and pass it around,`,
      `${countBottles(numBottles - 1)}...`,
    ];
};

const printLyrics = (numVerses: number) =>
  Array.from(Array(numVerses + 1), (_, i) => {
    console.log(
      lyricsForVerse(i, numVerses).map(capitalize).join("\n") + "\n"
    );
  });

printLyrics(99);