Libes, Don (1995). Exploring Expect: A Tcl-based Toolkit for Automating

Point-and-click interfaces, as opposed to a sensible command language, will always have their supporters and critics. We present an approach to developing a point-and-click interface based on the TCL/TK extension, Expect. Compared to the internal support of TCL/TK through packages like tcltk, rpanel, tkrplot, and others, the Expect approach is slower and less appropriate for animated displays. On the positive side, applications are very easy to de-velop, the very existence of R is hidden from the user, and the interactive nature of R is exploited fully. As an example, we present a toy application (a t-test or a regression), and a larger application for the analysis of treatment effects in experimental an