too many lines too long

Simon Peyton Jones simonpj at
Mon Nov 9 22:45:15 UTC 2015

In my view 80 chars is too short.  It was justified in the days of 80-column CRTs, but that just isn't a restriction any more.   I routinely edit in a much wider window.

Clearly there's a judgement call here.  But I'd prefer 120 cols say.


-----Original Message-----
From: ghc-devs [mailto:ghc-devs-bounces at] On Behalf Of Richard Eisenberg
Sent: 09 November 2015 21:03
To: ghc-devs Devs <ghc-devs at>
Subject: too many lines too long

Hi devs,

We seem to be uncommitted to the ideal of 80-character lines. Almost every patch on Phab I look through has a bunch of "line too long" lint errors. No one seems to do much about these. And Phab's very very loud indication of a lint error makes reviewing the code harder.

I like the ideal of 80-character lines. I aim for this ideal in my patches, falling short sometimes, of course. But I think the current setting of requiring everyone to "explain" away their overlong lines during `arc diff` and then trying hard to ignore the lint errors during code review is wrong. And it makes us all inured to more serious lint errors.

How about this: after `arc diff` is run, it will count the number of overlong lines before and after the patch. If there are more after, have the last thing `arc diff` outputs be a stern telling-off of the dev, along the lines of

> Before your patch, 15 of the edited lines were over 80 characters.
> Now, a whopping 28 of them are. Can't you do better? Please?

Would this be ignored more or followed more? Who knows. But it would sure be less annoying. :)

What do others think?

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