I'm exploring options here for a Read Evaluate Print Loop REPL on small embedded systems on small micro-controllers.
The main use I envisage is to run configuration and test commands on an embedded system using a terminal emulator on some host connected by serial USB/UART.
The REPL would need some language support to:
Call functions exported to it from the embedded system.
Define variables.
Control the flow of execution.
Be simple to use.
It would need to have a very minimal foot print for the base configuration.