I read the docs on eval but I'm still unclear on what problem it resolved.

Perhaps this simplified code will illustrate?

#!/usr/bin/env perl 
use strict;
use warnings;
use Time::Piece;

for my $input ('05/05/2000', 'notavaliddate') {
    my $date;
    if (eval { $date = Time::Piece->strptime($input, '%m/%d/%Y'); 1 })
+ {
        print "Parsed '$input' into '$date' with eval\n";
    } else {
        print "Attempted parsing of '$input' trapped by eval - life go
+es on\n";
    }
    if ($date = Time::Piece->strptime($input, '%m/%d/%Y')) {
        print "Parsed '$input' into '$date' without eval\n";
    } else {
        # Next line never executed because program dies
        print "Attempted parsing of '$input' trapped without eval\n";
    }
}

print "Run completed OK\n"; # This line will not be reached given bad 
+inputs
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Did you have capture brackets around the date ?

if($_=~/$first/) {          
   $_=~/(\d+\/\d+\/\d+)/;
#       ^             ^
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