Re: Re: [commit: packages/base] master: Improve error messages for partial functions in Data.Data (d0b74ca) (Gabor Greif)
Hi Gabor, Thank you for the feedback. You are right about spelling. I'll fix it. Regarding refactoring: If I understand you correctly your suggestion is to add new function which will wrap error message so the text will be less redundant. I'm not sure about it. From my experience it is better to leave error messages as simple as possible. Since when using functions in error messages it is possible that this function will fail and then you will get confusing error message (from inside function). So as a rule of thumb I never add another functions inside error processing (except the ones which makes message more meaningful). But that's of course just my point of view. It is also possible that I didn't understand your proposition correctly :-) -- Thanks Krzysztof
Hi, Am Donnerstag, den 02.01.2014, 10:54 +0100 schrieb Krzysztof Langner:
I'm not sure about it. From my experience it is better to leave error messages as simple as possible. Since when using functions in error messages it is possible that this function will fail and then you will get confusing error message (from inside function).
for most pure Haskell functions, you can be quite certain that they don’t fail, by following simple rules (complete patterns, no use of partial functions like head or fromJust). So while this is might be true in other programming languages, here you can put trust in Haskell’s type system – if it compiles, it works. Greetings, Joachim -- Joachim “nomeata” Breitner mail@joachim-breitner.de • http://www.joachim-breitner.de/ Jabber: nomeata@joachim-breitner.de • GPG-Key: 0x4743206C Debian Developer: nomeata@debian.org
participants (2)
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Joachim Breitner -
Krzysztof Langner