def _nt_label
start_index = index
if node_cache[:label].has_key?(index)
cached = node_cache[:label][index]
if cached
cached = SyntaxNode.new(input, index...(index + 1)) if cached == true
@index = cached.interval.end
end
return cached
end
i0 = index
i1, s1 = index, []
i2, s2 = index, []
r3 = _nt_alpha_char
s2 << r3
if r3
s4, i4 = [], index
loop do
r5 = _nt_alphanumeric_char
if r5
s4 << r5
else
break
end
end
r4 = instantiate_node(SyntaxNode,input, i4...index, s4)
s2 << r4
end
if s2.last
r2 = instantiate_node(SyntaxNode,input, i2...index, s2)
r2.extend(Label0)
else
@index = i2
r2 = nil
end
s1 << r2
if r2
if has_terminal?(':', false, index)
r6 = instantiate_node(SyntaxNode,input, index...(index + 1))
@index += 1
else
terminal_parse_failure(':')
r6 = nil
end
s1 << r6
end
if s1.last
r1 = instantiate_node(SyntaxNode,input, i1...index, s1)
r1.extend(Label1)
r1.extend(Label2)
else
@index = i1
r1 = nil
end
if r1
r0 = r1
else
if has_terminal?('', false, index)
r7 = instantiate_node(SyntaxNode,input, index...(index + 0))
r7.extend(Label3)
@index += 0
else
terminal_parse_failure('')
r7 = nil
end
if r7
r0 = r7
else
@index = i0
r0 = nil
end
end
node_cache[:label][start_index] = r0
r0
end