This is a typescript port of the code in https://github.com/ftrain/code-commonplace/blob/master/code/clojure/rhymes.org

rhymes.ts

let fs = require('fs')

const cmu_dict: string = fs.readFileSync('cmudict-0.7b', 'utf-8')

type Rhyme = string[]
type WordToRhyme = {
  [word: string]: Rhyme
};

const word_to_rhyme =
    cmu_dict.split('\n')
        .filter(line => !line.startsWith(';'))
        .map(line => line.split(/\s+/))
        .reduce((m: WordToRhyme, [word, ...phonemes]): WordToRhyme => {
          m[word] = phonemes.reverse();
          return m;
        }, {})


type TrieNode = {
  [syllable: string]: string|TrieNode|undefined,
  terminate?: string
};

const rhyme_to_words: TrieNode = (function() {
  let result: TrieNode = {};
  for (let [k, v] of Object.entries(word_to_rhyme)) {
    let cursor = result;
    for (let syllable of v) {
      const next = cursor[syllable];
      if (typeof next === 'string') {
        throw Error('Unexpected syllable: ' + syllable);
      } else if (next === undefined) {
        cursor = cursor[syllable] = {}
      } else {
        cursor = next;
      }
    }
    cursor['terminate'] = k;
  }
  return result;
})();

function findAllWords(m: TrieNode): string[] {
  let results = [];
  let stack = [m];
  for (;;) {
    let top = stack.pop();
    if (!top) {
      break;
    }
    for (let [k, v] of Object.entries(top)) {
      if (typeof v === 'string') {
        results.push(v);
      } else {
        stack.push(v ?? {});
      }
    }
  }
  return results;
}

function findRhymes(word: string): string[] {
  let rhyme = (word_to_rhyme[word.toUpperCase()] || []).slice(0, 3)

  let cursor: TrieNode = rhyme_to_words
  for (let syllable of rhyme) {
    const next = cursor[syllable];
    if (next === undefined || typeof next === 'string') {
      cursor = {};
    } else {
      cursor = next;
    }
  }

  return findAllWords(cursor)
}

console.log(findRhymes('adamant'));