Churning Theoretical knowledge into Practical Skills

Perl is a high-level, general-purpose, interpreted, dynamic programming language. Perl was originally developed by Larry Wall in 1987 as a general-purpose Unix scripting language to make report processing easier. Since then, it has undergone many changes and revisions and become widely popular amongst programmers. Larry Wall continues to oversee development of the core language, and its upcoming version, Perl 6. Perl borrows features from other programming languages including C, shell scripting (sh), AWK, and sed. The language provides powerful text processing facilities without the arbitrary data length limits of many contemporary Unix tools, facilitating easy manipulation of text files. Perl gained widespread popularity in the late 1990s as a CGI scripting language, in part due to its parsing abilities. In addition to CGI, Perl is used for graphics programming, system administration, network programming, finance, bioinformatics, and other applications. Perl is nicknamed "the Swiss Army chainsaw of programming languages" due to its flexibility and power. It is also referred to as the "duct tape that holds the Internet together", in reference to its ubiquity and perceived inelegance.

Introduction

What is Perl?

1.Perl Quick-Start Guide for Experienced Programmers

• Hello World
• Counting lines in a file
• Using a loop in Perl
• Using subroutines in Perl
• Using Perl's documentation

2.General Syntax

• Understanding how Perl uses whitespace
• Terminating statements with semicolons
• Creating comments
• Best practices for formatting code

3.Variables and Values

• Understanding values and variables
• Declaring numeric variables
• Declaring character string variables
• Declaring lists and arrays
• Pulling slices from arrays
• Understanding hashes and associative arrays
• Getting value pairs using the each function
• Understanding the undef value

4.Statements and Blocks

• Assigning values to variables
• Using statements and expressions
• Combining statements into blocks
• Understanding scope

5.Conditional Statements

• Understanding conditional statements
• Creating conditionals with if
• Extending conditionals with else
• Extending conditionals with elsif
• Building if statements with postfix conditionals
• Creating negative conditionals with unless
• Using the ternary conditional operator

6.Loops

• Understanding loops
• Creating loops with while
• Creating loops with until
• Iterating lists with foreach
• Iterating lists with for
• Using loop control statements
• Building loops with postfix statements

7.Special Variables

• Understanding special variables
• Using special variables
• Working with special file handles
• Using special constants

8.Operators

• Performing basic math with arithmetic operators
• Creating conditionals with comparison operators
• Combining conditionals with logical operators
• Reading file metadata with file test operators
• Creating a sequence with the range operator
• Combining strings with the concatenation operator
• Streamlining strings with quote operators
• Understanding operator precedence

9.Regular Expressions

• Understanding regular expressions
• Searching and replacing text with regular expressions
• Extracting matches with parentheses
• Matching wildcards
• Matching classes of characters
• Creating arrays with split

10.Subroutines

• Understanding subroutines
• Defining and calling subroutines
• Using arguments with subroutines
• Understanding scope and "my" variables
• Returning values from a subroutine

11.References and Data Structures

• Understanding values and references
• Defining array references
• Defining hash references
• Building mixed data structures

12.File I/O

• Understanding streams and files
• Using file handles
• Using the object-oriented interface for handling files
• Working with binary files

13.Built-In Functions

• Manipulating strings with built-in functions
• Working with numbers
• Manipulating lists and arrays with built-in functions
• Retrieving and formatting time

14.Modules

• Leveraging code with modules
• Understanding object-oriented and procedural modules
• Creating modules
• Understanding object and instance data
• Installing modules from CPAN on Mac and Unix
• Installing modules from CPAN on Windows

15.Documentation with POD

• Understanding POD
• Documenting with POD
• Exploring a POD document

16.New Features in Perl 5.10

• Using Perl 5.10
• Displaying text with say
• Selecting from multiple choices with given and when
• Keeping persistent variables with state

17.Exploring Web Development

• Exploring CGI
• Using a database
• Developing a module library