I have a hash and the keys are page names.

(snip)

I want to create another hash using the page names as the keys and the count() result as the values.

my %orig= # ...
my %new;
$new{$_}=however_you_get_it_from($_) for keys %orig;
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or

my %new=map { $_ => however_you_get_it_from($_) } keys %orig;
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or...