Your snippet wouldn't work because %ENV is a global variable, so when you change it in the inner scoper (inside the curlies) you're changing it outside, too. To localize the change, you can maybe do local %ENV; inside the inner block.

It's also possible You may also just want to save the value and reset it later.. 
my $save_term = $ENV{TERM};
$ENV{TERM} = "foo";
print `echo a \$TERM`;
$ENV{TERM} = $save_term;

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Update: rephrased to lessen the emphasis on the second (non-local) solution which is just an example of another possibility and not an advocation of the 'right' (or even 'good') way.

In reply to Re: Changing ENV values locally by davidrw
in thread Changing ENV values locally by Anonymous Monk

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