Regular Expressions

Concepts and Editorials

• Perl uses a concept known as Regular Expressions for its matching and substitution operator.
• Regular Expressions permeate the Unix world, and are common in everything from the terminal shell to the system libraries.
• Regular Expressions can get tremendously complex, but are tremendously powerfull. They are a power tool, and not for the faint of heart.
• The concepts behind Regular Expressions are quite simple, however, and can be simple to write, and can replace pages of convoluted code logic.
• Regular Expressions can be very difficult to read, but are generally reasonably quick to rewrite. They have been called write only code, and to some degree this is the case.
• The two main uses of Regular Expressions in Perl are matching and substitution.