Is there ever a situation in which declaring a variable twice in the same scope is useful? Conversely, is there ever a time when doing so will not cause problems?

Yes - when a variable is no longer needed, then there's no harm in redeclaring it and using it for a different purpose.

For example, imagine the following test script:

use Test::More;
use strict;
no warnings;

diag "Testing that 'uc' works.";
plan tests => 3;

my $result = uc 'foo';
is $result, 'FOO';

my $result = uc 'bar';
is $result, 'BAR';

my $result = uc 'baz';
is $result, 'BAZ';

[download]

Certainly different variables could be used for each test, or the my could be dropped from the second and third tests, but why should Perl insist upon it. The code above is perfectly clear, and runs fine.

In reply to Re^3: Help! My variables are jumping off a cliff! by tobyink
in thread Help! My variables are jumping off a cliff! by oko1

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