hadley/plyr — pull request #106 by vitoshka (2012-10-18 22:20:46+00:00)
Title: colwise messes replicated names 

Setdiff in strip_splits make names unique. This leads to an obscure bug which is very difficult to spot if you deal with large number of columns.

Example:

```R
> df <- data.frame(a = 23, a = 56, check.names = F)
> colwise(mean)(df)
a
1 23
>
```