Typically an advanced UI where one types into a REPL is called a 'Listener' in Lisp. Examples for Listeners: the MCL Listener, Genera's Listener, LispWorks List

Typically an advanced UI where one types into a REPL is called a 'Listener' in Lisp. Examples for Listeners: the MCL Listener, Genera's Listener, LispWorks Listener, the SLIME Listener and others. For an impression of a Genera Listener I would recommend to see Kalman Reti's Youtube video: https://www.youtube.com/watch?v=o4-YnLpLgtk https://www.youtube.com/watch?v=o4-YnLpLgtk He shows there the Lisp Machine Listener debugging/interacting with mixed Lisp and C code. MCL and LispWorks IDEs Listeners are running in an integrated editor. The running programming runs inside the development environment. SLIME's Listener uses an external editor (GNU Emacs) for the Listener. Genera has an integrated application as a Listener and that one is not based on an editor. That's also a significant difference if the Listener is an internal tool, compared to an externally attached tool. External: from a user point of view, I use an IDE and connect to a running Lisp. Internal: I use the IDE and spawn a new Listener window (which could be on another X11 screen in case of an X11-based GUI). Usually the integration with internal Listeners is higher, but they may be more fragile, since they share the process & UI with the running program. Using an editor as a base substrate has some advantages: one has usually better editing support in the Listener. But as Genera shows, a Listener does not need to run on top of an editor to be powerful. The Genera listener has for example full output recording, each listener is also a drawing plane and remembers all output and associates it with the displayed Lisp objects. That makes the interaction with code and data extremely convenient, a feature which is not provided by evaluating code from an editor buffer. SLIME provides a similar feature, but in a very limited way. The richer the Listener UI, the more of the interaction of the user will be in the Listener. Thus often an exclusive use of the editor to evaluate code is either a sign of a powerful editor integration or a weak Listener implementation. In Genera the Lisp listener is also not only a powerful data explorer, but also a shell with a lot of commands for exploring the Lisp system. A portable and in some ways slightly less polished / extensive version is the McCLIM listener. Example: https://mcclim.common-lisp.dev/static/media/screenshots/bundled/listener1.jpg https://mcclim.common-lisp.dev/static/media/screenshots/bund... Also a Lisp might provide Listeners as panes of application frames. Thus an application window (either a tool of the IDE or any application GUI window) includes a corresponding Listener as a pane. As a simple example I can open a LispWorks Inspector and add a Listener pane. Any result from evaluation in the Listener will be displayed in a Inspector, with history.