Introduction to the Perl Programming Language - Part 1

Agenda

• What is Perl for
• Development Environments (GUI)
• Type of Variables
• Print function
• First Program: HolaBarcamp.pl
• STDIN function
• Second Program: WelcomeAlBarcamp.pl
• Third Program: Basic Operations.pl
• IF statement

This will be the first installment of Programming in Perl, this material will be used for the exhibition at BarCamp Milagro where I will be an exhibitor, it divides it into parts so as not to make the post too big, I hope you like it.

All the files mentioned in the article can be downloaded from this link:

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For what to serve Perl

Perl is a multipurpose language, in which they can be done from small scripts to manage servers based on Unix o GNU / Linux, to make web pages, there are complete projects made in Perl

Development Environments

Currently on the market there are many development environments to program in perl of which we can name:

1.- SublimeText (Windows and GNU / Linux)

2.- Eclipse (Windows and GNU / Linux)

3.- OpenPerlIDE (Windows)

4.- Notepad ++ (Windows)

Type of Variables

In Perl as in all programming languages ​​there are different types of variables

* Scalars. Variables start with $, like $ variable. Strings of text or numbers are represented here.

* Arrays. Arrays start with @, like @variable. You can put whatever you want inside.

* Hash. Hashes start with%, as% variable. Both variables and data can be anything.

Scalar

$var1 = 33; #Esto es una Variables Global

My var=32; #Esto es una Variable Local

Arrays

@array = ( “uno”,”dos”,”tres” ); #Array 3 elementos

@array=(); #Array de x elementos (Indefinido)

Hash

%hash = ( 1, "uno", 2, "dos", 3, "tres" );

Print function

The function print as in the C ++ programming language, it is used to print a text string or the content of a variable on the screen

First Program: HolaBarcamp.pl

STDIN function

What we have worked for C o C++ have to remember the function scanf. Well, STDIN fulfills the same function which is to receive the values ​​entered by keyboard, but unlike scanf in which we had to tell it which value is going to be entered with STDIN, we only have to do this:

$variable=<STDIN>;

With STDIN you can enter text, number, alphanumeric, all this without defining how it was done with scanf:

scanf(“%d”, variable_tipo_entera);

Second Program: WelcomeAlBarcamp.pl

Third Program: Basic Operations.pl

With the above learned we can now make a program that performs the four basic operations

IF statement

The IF statement, as in any programming language, is used when we want to make validations or we need a process to be carried out when the if condition is met.