code: function TypedFeatureStructure(options) {
    this.type = options.type;
    if (!this.type) {
      this.type = options.signature.typeLattice.bottom;
    }
    this.features = {};
    this.aux_type = null;
    this.aux_features = {};
    this.forward = null;
    this.forward_mark = NO_GENERATION;
    this.unifact = null;
    this.unifact_mark = NO_GENERATION;
    this.label = null;
    this.printed = false;
    this.id = node_id_counter++;
    this.coreference = false;
    if (options.features) {
      this.setFeatures(options.features, options.signature);
    }
    this.lexicalString = null;
    this.incoming = {};
  }
docs: Constructor