Question: What are the qualities that you should have, when designing a programming language?

Philip Wadler answered on 16 Jun 2010:

You need to know the relevant mathematics. You need to know some of the general principles that underlie most programming languages: how variable binding works, how types work, how polymorphism works, and so on. You need a good sense of engineering and design. You need to know the relevant psychology, what do people find easy to do and what do people find hard to do. Most important, you need to be able to abstract, that is, to figure out what aspects of the problem people need to focus on, and which are details that can be ignored.