Perl hash basics: create, update, loop, delete and sort
Hashes are one of Perl’s core data types. This article describes the main functions and syntax rules for for working with hashes in Perl.
Old School Object Oriented Perl
If you need to write object oriented Perl code with no dependencies, then you need to use the old school Perl syntax. This article describes the main features of old school object oriented Perl including class declaration, constructors, destructors, methods, attributes, accessors and inheritance.
Read it
Dynamic variable names with a dereferencing block
Perl is remarkably flexible and allows you to achieve all kinds of wizardry with the language. One example of this is using a dereferencing block to use a scalar value as a variable name. This allows you to use variables with dynamic names.
Read it
Use Module::Version to get the version of an installed Perl module
Another cool way to get the version of a module
Read it
The conditional (ternary) operator
One way to reduce the verbosity of Perl code is to replace if-else statements with a conditional operator expression. The conditional operator (aka ternary operator) takes the form: logical test ? value if true : value if false.
Read it
Perl for loops
Perl’s for loops are a powerful feature that, like the rest of Perl can be as concise, flexible and versatile required. This article covers the core features for Perl’s for loops.
Read it
Test if the user is root
When Perl is executing a program, it maintains the user id of the process owner in a global variable ($<). When a Perl program is executed by root or a user with root privileges (e.g. using the sudo command), the user id variable is always set to zero. This can be checked at the command line:
Read it
List shortcuts: qw the quote whitespace operator
A popular way to build a list of literal quotes in Perl is to use the quote whitespace operator (qw). It’s terse, versatile and elegant. To see why, let’s look at a typical statement using a list of strings:
Read it
List all Perl modules installed via CPAN
A quick way to list all non-core modules installed via CPAN using the command line:
Read it
Modern Perl mecca: modernperlbooks.com
Although not precisely defined, Modern Perl programming refers to the use of best practice coding syntax, environment configuration tools, new Perl modules and the general joie de vivre associated with Perl since version 5.10.2. During this time the Perl language and available modules went through an upgrade of several tons of awesome, which resulted in a more concise, idiomatic syntax, and powerful new tools including web frameworks, ORMs and configuration managers.
Read it
Perl arrays 101 - create, loop and manipulate
Arrays in Perl contain an ordered list of values that can be accessed using built-in functions. They are one of the most useful data structures and frequently used in Perl programming.
Read it
Upgrade your list printing using field separator variables
A typical way to print every element of an array in Perl is using a foreach loop:
Read it
Repeat strings with the repetition operator Repeat strings with the repetition operator
You get the idea - Perl has a repetition operator (x) that repeats the scalar or list on its left by the number on it’s right (like multiplication).
Read it
Check your module POD using perldoc
Perl ships with a command-line program called perldoc that makes it easier to search and read Perl’s vast documentation in the POD markup language. If perldoc is called with the -F flag, it will display the POD markup of an input file - this can be useful when your are developing a new Perl distribution and want to check the appearance of the POD in your module before it appears on CPAN for all to see.
