// s = e.g. "(what, give) + (mrnuke, mrnuke's, mr + (nuke, nuke's)) + (url, address)"
static MMOPattern mmo_parsePattern(S s) {
  s = trim(tok_deRoundBracket(trim(s)));
  LS tok = javaTokWithBrackets(s);
  LS l = tok_splitAtComma(tok);
  if (l(l) > 1)
    ret new MMOPattern.Or(lambdaMap mmo_parsePattern(l));
  l = tok_splitAtPlus(s);
  if (l(l) > 1)
    ret new MMOPattern.And(lambdaMap mmo_parsePattern(l));
  if (startsWith(s, "!"))
    ret new MMOPattern.Not(mmo_parsePattern(dropFirst(s)));
  ret new MMOPattern.Phrase(unquote(s), isQuoted(s));
}

Began life as a copy of #1026018