A Minimal Run-Time Overhead Metaobject Protocol for Julia

Metaobject Protocols enable programmers to extend programming languages without the need to understand the lower level details of their implementation. However, designing these protocols presents two challenges: allowing programmers to limit their concerns to higher-level concepts and minimizing performance penalties in programs. In this work, we propose a metaobject protocol for the Julia programming language. Julia does not follow the traditional object-oriented paradigm. However, Julia's compilation approach allows for a considerable degree of code optimization through the exploration of run-time type information. Through the usage of Julia's run-time optimizations, it becomes possible to implement a metaobject protocol that combines user-extensibility with minimal performance penalties in run-time. This paper focuses on the development of a multiple inheritance method dispatch and method combination mechanisms with minimal run-time overhead