new PreSequence[][] {
new PreSequence[] {
new PreSequence(new Element[] { CharToken.leftBrace,
+ Repeat.maximal(Repeat.many0(nonTerminal("w"))),
((PreSequence)walk(tree, 0)).buildUnion(),
+ Repeat.maximal(Repeat.many0(nonTerminal("w"))),
CharToken.rightBrace
})
}