Map access involves finding the correct bucket and then checking for key equality. NaN is never equal to anything, so the equality check fails and item is not there.
On Sun, 2018-10-21 at 19:11 -0700, Aston Motes wrote: > Even though you can get at the values by iterating, I can't seem to > do so > with a direct reference to the NaN key: > https://play.golang.org/p/69m-LK7obHA > > On Sun, Oct 21, 2018 at 4:18 PM Burak Serdar <bser...@ieee.org> > wrote: > > > > > On Sun, Oct 21, 2018 at 4:59 PM Dan Kortschak > > <dan.kortsc...@adelaide.edu.au> wrote: > > > > > > > > > They are not inaccessible, they are just inaccessible via reflect > > > (at > > > the moment). > > > > > > https://play.golang.org/p/_EnLPRvrHAz > > > > > > fmt uses reflect to get the keys and values. With the addition of > > > a map > > > iterator type in reflect (https://tip.golang.org/pkg/reflect/#Map > > > Iter), > > > the behaviour you see now will change. > > Thanks, that makes sense. > > > > > > > > > > > > > On Sun, 2018-10-21 at 16:33 -0600, Burak Serdar wrote: > > > > > > > > Someone asked a question a few days ago related to this, and > > > > it's > > > > been > > > > bugging me since then. > > > > > > > > Is this an undefined behavior according to the spec? > > > > > > > > https://play.golang.org/p/RqgD492EZ9U > > > > > > > > The code results in a map with two NaN keys, both of which have > > > > nil > > > > values. I think having two NaN keys is reasonable, but I would > > > > expect > > > > them to be non-nil when iterated, > > > > > > > > Since they are inaccessible, would those map values be garbage > > > > collected? Or is there a hidden pointer somewhere in there > > > > where no > > > > one can reach? > > > > > > -- > > You received this message because you are subscribed to the Google > > Groups > > "golang-nuts" group. > > To unsubscribe from this group and stop receiving emails from it, > > send an > > email to golang-nuts+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 "golang-nuts" group. To unsubscribe from this group and stop receiving emails from it, send an email to golang-nuts+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
