You may want to reconsider what you've said here. 
use strict;
use warnings;
use Data::Dumper;


my %hash = (1 => 2, 3 => 4);
BLOCK: {
    local $hash{1} = 5;
    print Dumper \%hash;
}

print Dumper \%hash;

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What you've said is true for localizing lexical scalars; however localizing values in lexical arrays and hashes is no problem. See When to Still Use local(), item #3. Sorry if I've misread your intent.

#11929 First ask yourself `How would I do this without a computer?' Then have the computer do it the same way.

In reply to Re^4: use 'local' modifier to hashref element by kennethk
in thread use 'local' modifier to hashref element by schetchik

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