Whitespace woes

One very annoying aspect of software development in a team is whitespace. Many people use it differently. In a way it's unimportant, not least because it's literally invisible and so often overlooked. Yet it continues to cause problems which repeatedly waste time, and is especially distracting and troublesome for the many detail-oriented developers among us.

Clearly the only sane way to use whitespace in Perl is:

• 4 character indent
• only use spaces, never use tabs
• never allow any trailing whitespace

One of the worst violations of these rules is an indent composed of mixed tabs and spaces. This is a list of reasons why that's very wrong:

• When someone gets fed up and changes that whitespace to make it conform, it introduces noise into the code diff (they don't create a separate branch due to the overhead costs in a bureaucratic, audited environment).
• Different text editors and web interfaces all display the indent differently, making the code hard to follow.