How can I ensure that no null value is assigned to a variable using Perl grep function?

How to put value into a scalar variable when using Perl's开发者_运维百科 grep method?

For example, I have the following code and need to put the value from the per grep method into a scalar variable?

        my $variable = grep(/@/,@dataRecord);

if you mean grep return 1 element than

my ($variable) = grep(/@/,@dataRecord);

else you should use arrayref

my $variable = [ grep(/@/,@dataRecord) ];

If you only need one of the matching elements of @dataRecord, using grep might not be the most appropriate choice. That is because grep will check all elements no matter how many matches you want to extract.

You have to first decide which of the potentially more than one matching elements in @dataRecord you want. If you want the first matching element, you'd be better off using List::MoreUtils::firstval:

firstval BLOCK LIST
first_value BLOCK LIST

Returns the first element in LIST for which BLOCK evaluates to true. Each element of LIST is set to $_ in turn. Returns undef if no such element has been found.