[erlang-questions] Fwd: Must and May convention

[zxq9]

On 2017年09月28日 木曜日 12:32:32 you wrote:
> Interesting. Not so strictly speaking, some of the gen_server calls that do
> not change its state may be seen as 'pure' albeit relying on messaging, and
> a tool could probably figure out such calls automatically. And this
> definitely could help to figure out what' going on in a project.

Perhaps -- but you probably do NOT want a naked call there, because there
is no guarantee the process you called actually exists. Or is on the same
node. Or is calling some external resource not even related to Erlang to
figure out its response.

We could imagine an intermediate category of calls that are a sort of
"pure RPC", but the utility of this distinction may be pretty limited --
we can't (and shouldn't) know what is going on inside another process.

Anyway, it is worth exploring the idea, maybe. At the moment I'm looking
at a very limited goal: getting pure declarations to be a real thing. If
I had more time I would formally propose it and work on implementation --
but I have my hands full and a HUGE backlog of other, slightly higher
priority things I think will improve Erlang tooling at a more immediate
level of impact.

-Craig