getStateToAltMap static method

Map<ATNState, BitSet> getStateToAltMap(
  1. ATNConfigSet configs
)

Get a map from state to alt subset from a configuration set. For each configuration c in configs:

map[c.{@link ATNConfig#state state}] U= c.{@link ATNConfig#alt alt}

Implementation

static Map<ATNState, BitSet> getStateToAltMap(ATNConfigSet configs) {
  final m = <ATNState, BitSet>{};
  for (var c in configs) {
    var alts = m[c.state];
    if (alts == null) {
      alts = BitSet();
      m[c.state] = alts;
    }
    alts.set(c.alt);
  }
  return m;
}