Whoops, forgot the group on this. On 27 July 2015 at 18:10, Carlo Zancanaro <carlozancan...@gmail.com> wrote:
> You're generating two random things: the map, and the subset of the keys. > You can't generate the subset of the keys without first knowing the full > set of keys, so bind lets you make the subset generator depend on the > result of the map generator. > > I should also point out that shrinking isn't the only problem with your > original function. Normally in test.check you can repeat a test case by > providing a seed to the generator. With your original code it would be more > difficult to repeat a test case. > On 27/07/2015 5:14 pm, "Mayank Jain" <firesof...@gmail.com> wrote: > >> >> It also might be helpful to know that there is already a subset generator >>> available in this library >>> <https://github.com/gfredericks/test.chuck#generators>. >>> >> >> Thanks, this looks good, will check it out. >> >> >>> What you've done here might appear to work, but it will get you into >>>> trouble when test.check starts to shrink your inputs. When test.check runs >>>> your generators it relies you you using it as your only source of >>>> randomness, and so your use of `rand-int` will cause some problems. >>>> >>>> >> Ah yes, I didn't think of shrinking. >> Thanks a lot for your help! :) >> >> >> >>> The trick is to use the `bind` function to make a generator which >>>> depends on the value of another generator (in this case, to capture the >>>> generated map so you can call rand-subset with the correct set of keys): >>>> >>> >> >> I didn't get why I had to use a bind here. What if I had only used fmap? >> > -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups "Clojure" group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
