A Tangible Interface for Learning Recursion and Functional Programming

Recursion is a powerful programming technique which is notoriously difficult to master, especially in functional languages because they prominently feature structural recursion as the main control-flow mechanism. We propose several hypotheses to understand the issue and put some to the test by designing an open-source interactive interface based on a tangible block-world with augmented reality and software feedback. Stacks of blocks are used as an analogy for the list data structure, which enables the simplest form of structural recursion. After using this application, students are expected to transfer their training to directly write recursive programs in sequential Erlang, a purely functional language.