Input validation is an excellent place. 
my %is_legal = map { $_ => 1 } qw(
    y yes n no
);

my $answer;
{
    print "What is your answer? ";
    chomp( $answer = <> );
    $answer = lc $answer;
    last if $is_legal{ $answer };
    redo;
}

# Do something with $answer, which is now guaranteed to be 'y', 'yes',
+ 'n', or 'no'

[download]

------
We are the carpenters and bricklayers of the Information Age.

Then there are Damian modules.... *sigh* ... that's not about being less-lazy -- that's about being on some really good drugs -- you know, there is no spoon. - flyingmoose

I shouldn't have to say this, but any code, unless otherwise stated, is untested

In reply to Re: Useful uses of redo? by dragonchild
in thread Useful uses of redo? by kvale

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