In my previous post - downloading youtube videos with a Perl one-liner - I used Perl's special variable $_. This is just one of many Perl's special variables.

One day last year I decided to go through all the Perl's special variables carefully so I could become a better Perl programmer and make a cheat sheet which I could always keep on my desk and look things up when needed.

As I explained in the previous cheat-sheet post (awk's cheat sheet), the cheat sheets are for learning things better and not doing things blindly and looking the stuff each time up. Here is another example why cheat sheets are helpful - suppose you programmed for 5 hours and then sat back in your chair to relax for 10 minutes. You could relax by taking cheat sheet in your hands and just scan through it and remember a thing or two.

This cheat sheet contains all the perl's special variables, their description and examples where possible.

It can be nicely printed on one sheet of paper by having two pages per side. Two on one side and two on other. That's how I have printed it.

Available as usual in .doc and .pdf formats.

Download Perl's Special Variable Cheat Sheet

PDF document: perl.predefined.variables.pdf

MS Word (.doc): perl.predefined.variables.doc

See you next time!