Re: Mark partial functions as such

+1 from me too. How about also adding in (to the documentation) the pre-condition - i.e. an identification of the inputs for which it will terminate and produce a result (where this is possible to state, of course).

On 31 Aug 2018, at 03:05, Daniel Díaz Casanueva wrote:

+1 from me too. The partiality of a function seems to me like something that should be documented.

Best, Daniel

Am Fr., 31. Aug. 2018 um 02:10 Uhr schrieb Richard Eisenberg mailto:rae@cs.brynmawr.edu>: Proposal: Mark partial functions in `base` as partial

Motivation: I'm about to teach Haskell to a classful of beginners. In my experience, they will soon reach for functions like `head` and `tail`, because pattern-matching is foreign to them. I would love just to be able to say "Don't use partial functions", but many students will not easily be able to tell partial functions from total ones.

I do expect this problem to work itself out rather quickly, and then students will be able to identify partial functions, but loudly marking partial functions as partial seems like a small service to everyone and a bigger one to newbies. I don't see any downsides.

Thoughts?

Thanks, Richard _______________________________________________ Libraries mailing list Libraries@haskell.org mailto:Libraries@haskell.org http://mail.haskell.org/cgi-bin/mailman/listinfo/libraries http://mail.haskell.org/cgi-bin/mailman/listinfo/libraries _______________________________________________ Libraries mailing list Libraries@haskell.org http://mail.haskell.org/cgi-bin/mailman/listinfo/libraries

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