def _nt_optionally_labeled_sequence_primary
start_index = index
if node_cache[:optionally_labeled_sequence_primary].has_key?(index)
cached = node_cache[:optionally_labeled_sequence_primary][index]
if cached
node_cache[:optionally_labeled_sequence_primary][index] = cached = SyntaxNode.new(input, index...(index + 1)) if cached == true
@index = cached.interval.end
end
return cached
end
i0 = index
r1 = _nt_labeled_sequence_primary
if r1
r1 = SyntaxNode.new(input, (index-1)...index) if r1 == true
r0 = r1
else
r2 = _nt_unlabeled_sequence_primary
if r2
r2 = SyntaxNode.new(input, (index-1)...index) if r2 == true
r0 = r2
else
@index = i0
r0 = nil
end
end
node_cache[:optionally_labeled_sequence_primary][start_index] = r0
r0
end