substance/util/levenshtein.js

Substance is a JavaScript library for web-based content editing. It provides building blocks for realizing custom text editors and web-based publishing system. It is developed to power our online editing platform [Substance](http://substance.io).

export default function levenshtein (a, b) {
  const m = []
  for (let i = 0; i <= b.length; i++) {
    m[i] = [i]
    if (i === 0) continue
    const ib = i - 1
    for (let j = 0; j <= a.length; j++) {
      m[0][j] = j
      if (j === 0) continue
      const jb = j - 1
      m[i][j] = b.charAt(ib) === a.charAt(jb) ? m[ib][jb] : Math.min(
        m[ib][jb] + 1,
        m[i][jb] + 1,
        m[ib][j] + 1
      )
    }
  }
  return m
}