[R] Google's R Style Guide

[Duncan Murdoch]

On 8/28/2009 8:59 AM, Esmail wrote:
> Perhaps most of you have already seen this?
> 
>    http://google-styleguide.googlecode.com/svn/trunk/google-r-style.html
> 
> Comments/Critiques?

The rules are mostly reasonable, though they aren't the ones followed in 
the R source.  One bad rule is the one on curly braces:

An opening curly brace should never go on its own line; a closing curly 
brace should always go on its own line.

The problem is the second part.  If the closing brace is followed by an 
else clause, the else should go on the same line as the brace, or things 
will parse differently when pasted than they do in a function.  For 
example, this follows their style to the letter:

f <- function() {
   if (TRUE) {
     cat("TRUE!!\n")
   }
   else {
     cat("FALSE!!\n")
   }
}

and it works as intended, but if you cut and paste the lines in the body 
(starting with "if (TRUE)"), the else clause will be a syntax error.  If 
it had been formatted as

f <- function() {
   if (TRUE) {
     cat("TRUE!!\n")
   } else {
     cat("FALSE!!\n")
   }
}

it would work even when cut and pasted.

Duncan Murdoch


> 
> Thanks,
> Esmail
> 
> ps: Reminds me of PEP 8 for Python
> 
>      http://www.python.org/dev/peps/pep-0008/
> 
>      Maybe not that surprising since Python is also one of the main languages
>      used by Google.
> 
> ______________________________________________
> R-help at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.