hadley/scales — pull request #16 by jiho (2012-03-27 13:10:59+00:00)
Title: Add a warning when the shape palette is exceeded

This warning was present in ggplot before and is necessary to understand why
shapes beyond the 6th are suppresses. But this being outside of the scope of
ggplot, I did not know how to phrase the warning exactly.

For information, the warning in ggplot was:
```
scale_shape_discrete can deal with
a maximum of 6 discrete values, but you have 11. See ?scale_manual for a
possible alternative
```