Learn how to use parentheses to extract matches from a regex.
- [Voiceover] In a scalar context,…the regular expression operator…returns a logical value of true or false.…Here is a working copy of match.pl…from chapter nine of the exercise files.…And here we're just checking to see if a match is found,…and we have a logical "if" statement,…and when I run it, it says "True",…or, if there is no match, then it'll say "False".…Sometimes it can be useful to know what the matches are,…rather than just did it match.…
And you can do this with parentheses like this.…If I put the word "line" in parentheses,…and instead of "True" here,…I say "match is $1",…and instead of "False", I can just say "No match".…And now when I run this, it says "match is line",…and there is the text, the actual text that it matched.…So, this is especially useful with wildcards.…
For example, if I change this to "..is"…and I run it,…now it matches the first time it finds two characters…followed by "is", which is the word "This",…and it shows that in our results.…You can extract more than one match…with $2 and $3, et cetera.…
Watch to learn the details of the Perl syntax, from variables, conditionals, loops, and data structures to regular expressions, functions, and references. A quick-start guide is included for experienced developers who want to get up and running with Perl 5 fast, and the entire course is recommended for both new and experienced programmers alike. Later chapters cover file handling and reusing code with Perl modules, plus Perl best coding practices.
- Understanding Perl's general syntax and the anatomy of a Perl script
- Writing statements and expressions
- Creating assignments
- Working with variables and strings
- Using data types effectively
- Defining logical flow with conditionals and loops
- Using special variables
- Using Perl operators
- Performing simple Perl programming tasks with expressions
- Matching data
- Defining and calling functions
- Using references
- Handling files in the file I/O
- Using built-in functions
- Reusing code with modules
- Coding with Perl best practices
Skill Level Intermediate
1. Setting Up
About Perl3m 36s
2. Quick Start
3. Basic Syntax
4. Values and Variables
7. Special Variables
9. Regular Expressions
11. References and Structures
12. File I/O
13. Built-In Functions
15. Best Practices
- Mark as unwatched
- Mark all as unwatched
Are you sure you want to mark all the videos in this course as unwatched?
This will not affect your course history, your reports, or your certificates of completion for this course.Cancel
Take notes with your new membership!
Type in the entry box, then click Enter to save your note.
1:30Press on any video thumbnail to jump immediately to the timecode shown.
Notes are saved with you account but can also be exported as plain text, MS Word, PDF, Google Doc, or Evernote.