What programming language features are well suited for developing a live coding framework?

Question

I would like to build a \"live coding framework\".

I should explain what is meant by \"live coding framework\". I\'ll do so by comparing live coding to traditional codin

Answer 1

I'm working on a live coding feature for PyDev's Python editor. It was inspired by Bret Victor's Inventing on Principle talk, and I've implemented a program state display as well as turtle graphics. They both update as you type your Python code in Eclipse.

The project is hosted on GitHub, and I've posted a demo video, as well as a tutorial.

The main features of Python that I used were abstract syntax trees and dynamic code execution. I take the user's code, parse it into a tree, then instrument any assignment statements, loop iterations, and function calls. Once I've instrumented the tree, I execute it and display the report or draw the requested turtle graphics.

I haven't implemented the swapping feature that other answers discuss. Instead, I always run the code to completion or a time out. I envision live coding as an enhancement to test-driven development, not as a way to hack on a live application. However, I will think more about what swapping out pieces of a live application would let me do.