Actually lexical variables can be localized. 
use strict;
my %hash = qw(hello world);
print "$hash{hello}\n";
{
  local $hash{hello} = "WORLD";
  print "$hash{hello}\n";
}
print "$hash{hello}\n";

[download]
There is no technical reason why this isn't doable for the original hash as well. The only reason why it cannot currently be done is that it is considered a likely cause of confusion.

In reply to Re (tilly) 3: 'use strict' Rejecting Local Hash by tilly
in thread 'use strict' Rejecting Local Hash by Anonymous Monk

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