Re: [PATCH 3/5] sequencer: sequencer state is useless without todo

Ramkumar Ramachandra <artagnon@gmail.com> writes:

A function to externalize our internal representation like sha1_to_hex() is not such a big problem in practice, as the lifetime of its result is inherently much shorter.

Anybody sane with a datum that eventually needs to be externalized will keep it in its internal representation as long as possible, and then call such an internal-to-external function just before it becomes absolutely necessary to externalize it (e.g. calling printf(), packet_write(), etc). This is because the whole point of having an internal representation (e.g. when our code talks about an object name, we always use "unsigned char[20]") is so that all of our functions can use that representation to pass it around. It would be insane to call such a function earlier than necessary, having to pass external representation around.

On the other hand, resolve_ref() is an interface to canonicalize external representation into a form suitable to be kept and passed around as its internal representation. The lifetime of its result fundamentally has to be a lot longer than that of functions that work in the opposite direction, e.g. sha1_to_hex().