travisf
I picked this pattern up from another dev and have made fairly extensive use of it with Multis:
@multi Multi.new()
...
@multi
|> Multi.put(:params, params)
|> Multi.run(:somefunc, &some_func/2
This ensures that pipechains start with a raw value and, I think, it looks a little cleaner. Does anybdy else do this? Are there any articles on this pattern? It’s fairly simple but there is some nuance due to the constraints of module attributes (I’ve only done it with Ecto.Multi.new/2 and raw values), I wonder if you would run into problems during compile time if you tried it with modules in your project. Of course you couldn’t do it with a function in the same module.
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lud
I believe there is an option to allow arity-0 functions with this rule!
dimitarvp
I should have probably said this because this is what I ended up doing in my last 3 projects.
sodapopcan
I like the suggestions for when I accidentally do stuff like:
And credo is like, “You dummy, just use
flat_map!” It’s especially nice when you upgrade Elixir and it shows you all the places you can improve with stuff in the new version.…though I suppose this “artificial intelligence” everyone keeps talking about can also do that.
I do like the linting a lot, I just disable a bunch of checks.
dimitarvp
Yeah same, I use Credo as an advisor a few times and then just drop it. It’s been helpful but not by a lot.
andyleclair
We don’t use that rule at work (we
cp from project to projectmaintain a custom set of credo rules), it’s one of the most annoying rules. For my personal projects, I don’t use Credo at all!dimitarvp
It has been a while since I religiously used Credo but I have to say that if I understand that rule correctly then I disagree with it. If for no other reason than this thread exactly: it’s completely valid to start a pipe with a value that’s generated by a function i.e.
Ecto.Multi.new().andyleclair
Sorry, what I meant was “use a credo rule to enforce this”
sodapopcan
I was confused by “make sure it starts with a raw value” and how this pattern would solve it. I probably should have just asked but instead I ass-u-me’d you meant to ensure you use
Ecto.Multi.new()over%Ecto.Multi{}. Credo in this case could just make sure that the latter isn’t used anywhere other than on the left hand side of a pattern match (or guard, I suppose).dimitarvp
As a guy working with Elixir for 8 years now, I am confused as well.
al2o3cr
I’d be surprised if starting a chain with
Multi.new()triggers that Credo check - there is specific code to allow that shape when there are no args:https://github.com/rrrene/credo/blob/v1.7.5/lib/credo/check/refactor/pipe_chain_start.ex#L205-L211