def _nt_known_tokens
start_index = index
if node_cache[:known_tokens].has_key?(index)
cached = node_cache[:known_tokens][index]
@index = cached.interval.end if cached
return cached
end
i0 = index
if has_terminal?("7bit", false, index)
r1 = instantiate_node(SyntaxNode,input, index...(index + 4))
@index += 4
else
terminal_parse_failure("7bit")
r1 = nil
end
if r1
r0 = r1
else
if has_terminal?("8bit", false, index)
r2 = instantiate_node(SyntaxNode,input, index...(index + 4))
@index += 4
else
terminal_parse_failure("8bit")
r2 = nil
end
if r2
r0 = r2
else
if has_terminal?("binary", false, index)
r3 = instantiate_node(SyntaxNode,input, index...(index + 6))
@index += 6
else
terminal_parse_failure("binary")
r3 = nil
end
if r3
r0 = r3
else
if has_terminal?("quoted-printable", false, index)
r4 = instantiate_node(SyntaxNode,input, index...(index + 16))
@index += 16
else
terminal_parse_failure("quoted-printable")
r4 = nil
end
if r4
r0 = r4
else
if has_terminal?("base64", false, index)
r5 = instantiate_node(SyntaxNode,input, index...(index + 6))
@index += 6
else
terminal_parse_failure("base64")
r5 = nil
end
if r5
r0 = r5
else
@index = i0
r0 = nil
end
end
end
end
end
node_cache[:known_tokens][start_index] = r0
r0
end