Hint: Suggest NumericUndescores

[alanz]

For a literal string > 3 digits, and a GHC version that supports it.

cc @ndmitchell could this make sense as a hlint thing?

[ndmitchell]

Certainly possible. However, HLint doesn't have a good notion of what GHC version you are supporting, so I usually wait til it's fairly commonly deployed before suggesting new features (e.g. it recently added suggestions for lambda case) - so likely to be a while. Also a question of whether it's generally viewed as positive - my guess is at a certain threshold it is (say 6 digits?)

[alanz]

@ndmitchell

HLint doesn't have a good notion of what GHC version you are supporting

This is why I did not make an issue on hlint itself, at this point. And having a threshold does make sense.

[lorenzo]

My personal threshold in other languages is 5 digests. I have trouble differentiating 100000 from 1000000

[ndmitchell]

I have raised ndmitchell/hlint#577 and ndmitchell/hlint#578. You might want to close this, if you are happy that this is an HLint concern. Note that I suspect it will be months before I get around to this, but happy to take patches in HLint.

[alanz]

Thanks. I think I will keep it open for now, it may be simple enough to do.

And there are actually two parts to it, adding the pragma and offering to insert it into numbers.

And even check for weird grouping in a number, e.g. 1_000_00 where someone edited it and didn't adjust again.