Just to pick on the first one that popped out, using spaces over tabs. Don't get me wrong, I agree with it, but I know it's contentious, and would prefer to see something that expanded on why.
This is discussed in Perl Best Practices, page 20, "Indent with spaces, not tabs"
. Quoting Conway:
Tabs are a bad choice for indenting code, even if you set your editor's tabspacing to four columns. Tabs do not appear the same when printed on different output devices, or pasted into a word-processor document, or even just viewed in someone else's differently tabspaced editor.
Not being an "expert book author", many folks here won't listen to me, so I prefer to point them to a well-respected reference, such as PBP.
For some of these layout rules (e.g. brace placement), we already fought a war some years ago and I don't want to reopen old wounds. With over one million lines of existing code, it doesn't seem worthwhile to change longstanding company code layout conventions.
I know you have lots of links, but, without going through each one manually, it's difficult to know (in general) which link defends which rule. Some are obvious, but not all, so you should still have as direct of links as possible for most items.
Agreed. I'll try to provide a reference/s for each rule. I expect that will prove to be important for some folks here who may object to blindly accepting a rule without a supporting reference.