Abstract
Tcl is a command language library for embedding into other applications. It is often touted as the best language for this purpose and it is only natural that this claim should be investigated. This paper assists in that investigation by describing experiences over seven years with Expect. These experiences may help other extension language see some of the challenges that a single extension had to deal with while evolving at the same time as Tcl. Tcl and Expect users may also use these war stories to gain insight into why Expect works and looks the way it does today.