in reply to Iterating over an hash while removing keys
You don't have to call scalar. Using a void context resets the iterator without even checking the keys at all.
- scalar(keys %$hash); # Force reset + keys %$hash; # Force reset
Update: Documented in keys:
> In particular, calling "keys" in void context resets the iterator with no other overhead.
map{substr$_->[0],$_->[1]||0,1}[\*||{},3],[[]],[ref qr-1,-,-1],[{}],[sub{}^*ARGV,3]
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