Re: [Early Feedback] Pattern matching

On 25 June 2024 21:24:32 BST, Rob Landers <rob@bottled.codes> wrote: >The only way you’d observe this (that I can think of) is by performing a for-each loop over >the array. There are many ways you can observe the difference between an absent key and a null value; here are just a handful off the top of my head: - array_key_exists() (that's literally its purpose!) - array_keys() - count() (if the array held "an infinite number of nulls", we should return infinity for every array!) - json_encode() - print_r(), var_dump(), var_export() - extract() It may be questionable to give meaning to the difference in some of these cases, but different it definitely is. > If we don't like it, we can always create an RFC to treat non-existent keys as an error > instead of a warning. I believe that is the explicit intention or desire of those who raised it from Notice to Warning. It would certainly prevent some bugs where a typo leads to the wrong key being accessed. Personally, I'd like to see a few use cases catered for first, like $counters[$key]++ and $groups[$key][] = $value; Perhaps by introducing some equivalent of Python's "defaultdict". Because I do agree that the current behaviour is useful sometimes (even if I disagree in how to describe it). Regards, Rowan Tommins [IMSoP]