Sorry if this is a dim question - I've tried various permutations of dereferencing and I can't make it go. If I want to merge %old into %new, I'd use a hashref: 
@old{keys %new} = values %new;

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But what if, instead of hashes I have hash references? In my case this happens because I'm merging the output of two DBI calls, having fetched my data by doing $sth->fetchrow_hashrefs. I could just do 
my %old = %$old;
my %new = %$new;

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and then proceed as before; but that seems like a needless proliferation of data structures. And in fact, having written this out, I realise I could also use $sth->fetchrow_array to get my data from the db, and then create a single new hash to store the elements from my two new hashes.

But that still feels like too many steps. Is there a syntax for doing hash slice operations on hashrefs? Or some other one liner to merge two hashrefs?

§ George Sherston

In reply to Slicing a hashref by George_Sherston

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