Solved

How to gurantee grep return 1 or 0 in Perl

Posted on 2011-03-25
1
351 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
ID: 35219226
$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

Courses: Start Training Online With Pros, Today

Brush up on the basics or master the advanced techniques required to earn essential industry certifications, with Courses. Enroll in a course and start learning today. Training topics range from Android App Dev to the Xen Virtualization Platform.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

A year or so back I was asked to have a play with MongoDB; within half an hour I had downloaded (http://www.mongodb.org/downloads),  installed and started the daemon, and had a console window open. After an hour or two of playing at the command …
There are many situations when we need to display the data in sorted order. For example: Student details by name or by rank or by total marks etc. If you are working on data driven based projects then you will use sorting techniques very frequently.…
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…
Along with being a a promotional video for my three-day Annielytics Dashboard Seminor, this Micro Tutorial is an intro to Google Analytics API data.

785 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