Avoid using non-lexical variables. [Lexical Variables]
Don't use package variables in your own development. [Package Variables]
If you're forced to modify a package variable, localize it. [Localization]
Initialize any variable you localize. [Initialization]
use English for the less familiar punctuation variables. [Punctuation Variables]
If you're forced to modify a punctuation variable, localize it. [Localizing Punctuation Variables]
Don't use the regex match variables. [Match Variables]
Beware of any modification via $_. [Dollar-Underscore]
Use negative indices when counting from the end of an array. [Array Indices]
Take advantage of hash and array slicing. [Slicing]
Use a tabular layout for slices. [Slice Layout]
Factor large key or index lists out of their slices. [Slice Factoring]