I gave a talk at San Francisco PHP last week all about what it takes to start building a programming language. For the example, I have built out a small implementation of PHP in JavaScript I called PHP.js. We talked about the process of what it takes to build a programming language, as well as why programming languages are made, and some of the decisions that get baked into them while doing so. It was a fantastic group of people and I had a lot of fun giving the talk.
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