A eval may refer to any of the following:
Example of eval in Perl
my $one = 1; my $two = 2; my $total = 0; my $example = '$total = $one + $two'; eval $example; print $total;
In the above example, the string stored in the $example variable is executed using the eval command. A programmer could take this expression further by executing a complete Perl program stored in another file.