Perl Notes

Perl is a powerful yet ugly programming language. Sadly, it is based on too much symbolic syntax rather on a grammar that lends itself to readability and maintainability. A bad programmer can program worse in Perl, but a good programmer should know better than to be tempted by what Perl has to offer.

Perl is a strong language, but has evolved beyond its original scope. Writing too much Perl code can make your fingers curl in strnage directions, from all the shift-symbols that is required. My approach has been to write Perl in a manner that any C programmer can read, and not to use syntaxes that are not required that lead to confusion for myself and future programmers. I am trying not to write a complete Perl reference. That would be too long and is found on the perldoc site. Instead, I am trying to show a subset of Perl that I prefer to use on good style. Perl has a lot of implied variables that I prefer not to use if I can avoid it. This is therefore my style guide, not the general Perl public’s style.

I like Perl. Creator Larry Wall and the Perl team have done an excellent job with it. It has a large learning curve, and a large wealth of knowledge to master. The CPAN libraries give Perl an excellent method of building sophisticated applications without having to build all the plumbing in a project.

An excellent book is the definitive one: Programming Perl by the Perl giants, Wall, Chistiansen, and Orwant.

1. Perl Program Structure
2. Statements, Loops, and Conditionals
3. Variables and Data
   1. Numbers and Mathematical Operations
   2. Strings and Text Operations
   3. Boolean, True/False, and Operations
   4. Scalars--Simple Variables
   5. Arrays
   6. Associative Arrays, or Hashes
   7. References
   8. Tables and Multi-Dimentional Arrays
   9. Data Structures
4. Libraries
5. Objects
6. File I/O
7. Regular Expressions
8. Database Access
9. Command-line programs