The current R-devel now warns about passing vectors of length > 1 to if(). There seem to be a *lot* of such misuses amongst packages, including in the recommended packages lattice and mgcv. Since S warns, this is almost entirely confined to packages originally written for R. Would package developers please check their packages under R-devel at their convenience. I would be interested to hear of any misuses in R itself: several have come to light but more may be lurking. -- Brian D. Ripley, ripley@stats.ox.ac.uk Professor of Applied Statistics, http://www.stats.ox.ac.uk/~ripley/ University of Oxford, Tel: +44 1865 272861 (self) 1 South Parks Road, +44 1865 272860 (secr) Oxford OX1 3TG, UK Fax: +44 1865 272595