That's one of the points of use warnings. If you are using uninitialized variables all over the place, then perhaps a review of the code is necessary. Below I have thrown together an example of two scripts that do the exact same thing... except that one produces warnings and one doesn't :)

    #!/usr/bin/perl
    # The 'bad' version - produces warnings
    use strict;
    use warnings;

    my $name;
    # perhaps some code to get user's name
    # { ... }

    print 'My name is ' . $name;
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    #!/usr/bin/perl
    # The 'good' version - produces no warnings
    use strict;
    use warnings;

    my $name;
    # perhaps some code to get user's name
    # { ... }

    # The key line. Set a default value, even if blank.
    $name ||= "";

    print 'My name is ' . $name;
[download]