Solved

How to gurantee grep return 1 or 0 in Perl

Posted on 2011-03-25
1
328 Views
Last Modified: 2012-08-13
Hi,
Is there a chance for variable $myoption not to have any value?

my $myoption = grep(/somename/, @myarray);


If there is, then how can I make it 0 in a smart and safe way. Otherwise it will be 1 I guess.

Thanks,
0
Comment
Question by:Tolgar
1 Comment
 
LVL 26

Accepted Solution

by:
wilcoxon earned 500 total points
Comment Utility
$myoption will always be 0 or 1 or more.  What you are saying is:

my $myoption = scalar(grep(/somename/, @myarray));

so $myoption will always contain the number of items that matched the grep.  If nothing matched, it will be 0.  Otherwise, it will be a count of how many things from @myarray matches somename.
0

Featured Post

How your wiki can always stay up-to-date

Quip doubles as a “living” wiki and a project management tool that evolves with your organization. As you finish projects in Quip, the work remains, easily accessible to all team members, new and old.
- Increase transparency
- Onboard new hires faster
- Access from mobile/offline

Join & Write a Comment

On Microsoft Windows, if  when you click or type the name of a .pl file, you get an error "is not recognized as an internal or external command, operable program or batch file", then this means you do not have the .pl file extension associated with …
Many time we need to work with multiple files all together. If its windows system then we can use some GUI based editor to accomplish our task. But what if you are on putty or have only CLI(Command Line Interface) as an option to  edit your files. I…
Explain concepts important to validation of email addresses with regular expressions. Applies to most languages/tools that uses regular expressions. Consider email address RFCs: Look at HTML5 form input element (with type=email) regex pattern: T…
This tutorial demonstrates a quick way of adding group price to multiple Magento products.

728 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question

Need Help in Real-Time?

Connect with top rated Experts

9 Experts available now in Live!

Get 1:1 Help Now