If/else blocks should not have a negated condition in if.

[seantanly]

In writing if/else statements, I would normally prefer to place the short shorter block in front, and leave the larger block behind. If it's written the other way round, the reader might miss the else clause.

For example,

if ! valid(item) do
  {:error, :invalid_item}
else
  ... processing ...
  ...
  {:ok, result}
end

It is not every time we have the opportunity to rewrite the valid/1 method to invalid/1 such that there isn't a negation in the if clause. And we probably agree in not using unless/else even in such situations.

[rrrene]

I certainly would not argue against doing this. The "rule of thumb" should be: Put the positive case first.

However, your example is exactly the reason why we will have some way to disable checks on a per-case basis in Credo v0.3.0!

[seantanly]

Thanks! Looking forward to Credo v0.3.0! 👍

[rrrene]

@seantanly Credo v0.3.0 now includes support for a @lint attribute. See CHANGELOG for further details.

What do you think?

[seantanly]

Thanks for @lint! And together with .credo.exs gives us full ability for customization.