With s/and, conformed values flow through the predicates. This allows you to take advantage of structured values from early preds in later preds, so you're not having to re-understand the structure. (There are cases where having a non-flowing s/and would be useful and we've talked about adding that since way back, still TBD). For single values, there's not much difference, but it matters when you've got more structure, either from regex (really s/& then) or s/or, etc.
With s/merge the idea is to combine 2 or more map specs and "merge" their specs, both during conform and gen. The mental picture I have is that the same data flows into all the merged preds in parallel (whereas s/and snakes them through in serial order). I don't have a good example at hand that illustrates where is critical, but certainly in cases where you combining s/keys with a collection view of map tuples with s/coll (sometimes called "hybrid maps"), this is essential. On Friday, August 17, 2018 at 2:36:23 PM UTC-5, Jenny Finkel wrote: > > Sorry, I meant to file a bug and even try to write a fix, but I was very > pregnant at the time and then I gave birth so it sort of fell by the > wayside. I'm interested in understanding why non-flowing behavior on > conform is expected/desired behavior. I've found that when clojure design > decisions go contrary to my intuitions, I usually learn a lot from > understanding the design motivation. Would you mind explaining? > Cheers, > Jenny > PS - I did try to google for an answer, and I found the thread where the > docstring for merge got updated to reflect this, but I couldn't find an > explanation. > > On Thu, Aug 16, 2018 at 7:00 PM, <shlomivak...@gmail.com> wrote: > >> Thank you for explaining! >> >> Just in case, I opened a bug here >> https://dev.clojure.org/jira/browse/CLJ-2388 >> >> On Thursday, August 16, 2018 at 6:47:30 PM UTC-7, Alex Miller wrote: >>> >>> The non-flowing behavior on conform is expected behavior. >>> >>> Failure to roundtrip conform then unform is a bug (so I'd so the bug >>> here is in unform). >>> >>> On a quick search, I don't believe this was filed, but I could have >>> missed it. >>> >>> On Thursday, August 16, 2018 at 8:28:54 PM UTC-5, shlomi...@gmail.com >>> wrote: >>>> >>>> Achhh, just spent the last few hours fighting this unexpected behavior >>>> with s/merge, until I finally came to realize that this is what it was.. >>>> >>>> I see this thread is quite old, did anyone open a bug for it as >>>> mentioned above? >>>> >>>> @Alex, you said this was the expected behavior, but then asked to open >>>> a bug because it does not round-trip.. I am slightly confused, does the >>>> problem lie in this "expected" behavior, or does it lie in s/unform? How >>>> would such a bug be closed? >>>> >>>> Thanks, >>>> Shlomi >>>> >>>> On Thursday, June 1, 2017 at 6:24:25 AM UTC-7, Alex Miller wrote: >>>>> >>>>> You can file a bug on the s/merge unform - anything that doesn't >>>>> roundtrip should be a bug. >>>>> >>>>> On the coll-of one, I thought that was just fixed in the latest >>>>> spec.alpha release (see https://dev.clojure.org/jira/browse/CLJ-2076) >>>>> - are you using latest there? >>>>> >>>> -- >> 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 a topic in the >> Google Groups "Clojure" group. >> To unsubscribe from this topic, visit >> https://groups.google.com/d/topic/clojure/r8WO24rHsi0/unsubscribe. >> To unsubscribe from this group and all its topics, send an email to >> clojure+unsubscr...@googlegroups.com. >> For more options, visit https://groups.google.com/d/optout. >> > > -- 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.
