On Fri, Apr 09, 2021 at 03:11:10PM -0700, Junio C Hamano wrote: > > I dunno. That would probably be hard to represent via "git config > > --type". And some callers probably do care about "auto" versus "true". > > It would work well for codepaths where computing the default value > is cheap (or even possible). > > I think the point of using "auto" is to delay the decision as late > as possible. E.g. in-core parsed config and attribute may still > want to stay "auto", until we actually get our hands on the blob > contents to see if it is binary, until we know how heavily loaded > the system is, until we know isatty(1), etc. Some are cheap to > compute in advance, some are expensive and impossible until we meet > the data. Hmm, yeah, that's the "do care about auto versus true" thing. > So I still think the canonical use pattern for the "auto" thing is > > is_frotz = git_parse_bool_or_auto(value); > > ... arbitrary number of things can happen here > ... the above may even be done in a git_config() > ... callback, and is_frotz may not even be used. > > if (is_frotz == AUTO) > is_frotz = auto_detect_frotz(); > > if (is_frotz) > ...; /* do the frotz thing */ > else > ...; /* do the non-frotz thing */ That makes sense. Usually we represent "undecided" in such a tristate with -1, so something that returned -1/0/1 would feel very natural to me (and probably wouldn't need symbolic constants even). But -1 is also error. So a function like: int git_parse_tristate(const char *value, int *out); which returned success/error via its return value, and put the value into "out" would feel pretty natural to me. I dunno. I admit I don't care _that_ much, but somehow Ævar's series have a way of sniping me into responding anyway. :) -Peff
