eltclsh (editline Tcl shell) is an interactive
shell for the Tcl programming language. It
provides command line editing, history browsing,
and variables and command completion thanks to
editline features. The completion engine is
programmable in a way similar to tcsh, and comes
with built in completion for the entire Tcl
language by default. The package also provides
elwish, an interactive interpreter for the Tk
toolkit. You need the editline library in order to
compile eltclsh.