Re: Arrow Operator Questionby kcott (Archbishop)
|on Mar 26, 2023 at 11:45 UTC||Need Help??|
[Note: $a (and $b) are special variables; it's best to only use these for their intended purposes to avoid unexpected side effects; I've replaced $a with $h in the code below. Also, '//undef' is completely superfluous: if the LHS is undef, use undef instead. :-)]
Perl will autovivify as needed. It requires 'c' to check for 'd', so that key is autovivified. The 'd' key either exists and has a value or it doesn't exist and the value is undef: no autovivification is needed here.
You can use exists() to check for 'c'; only attempting to get a value for 'd' if 'c' exists. That can become unwieldy when there are multiple levels of keys; if you think autovivification is a problem, simply allow it then delete() afterwards.
The following code has examples which demonstrate these points.