Use the ref() function to find the type of a reference.
- [Voiceover] Sometimes you may need…to know the type of a reference,…so you can process it accordingly.…Perl provides the built-in function "ref" for this purpose.…Here is a working copy of ref.pl…from Chapter 11 of the Exercise Files.…And you will notice up here around line seven,…I declare a reference to an anonymous array,…and in line eight, I declare a reference to anonymous hash.…So, on line seven it's an array ref,…and on line eight it's a hash ref.…
And then I call display_ref twice, once with each of these,…and display_ref simply uses the ref function…to display the type of the reference.…So when I run this, you'll notice that we have two results,…one says "array", and one says "hash".…The display_ref for the array reference…displays the word "array",…and for the hash reference, it displays the word "hash".…And that's because the ref function right here…returns a string,…and the string is a representation…of type of reference it is.…
So, for an array reference, it will say "array",…and for a hash reference, it will say "hash".…
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
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