Stop Designing Languages. Write Libraries Instead

Summary

"Stop Designing Languages. Write Libraries Instead."Patrick S. Li - May 29, 2016I had a friend tell me recently that all programming languages seem very similar to each other. They all have variables, and arrays, a few loop constructs, functions, and some arithmetic constructs. Sure, some languages have fancier features like first-class functions or coroutines, but he doesn't consider himself an expert programmer anyway and doesn't use those features.What really makes a programming language productive for him, he says, are the libraries it comes with. For example, he got into programming by using the popular Ruby on Rails web framework. There is no way that he could have written a full database-driven web stack by himself, nor is he interested in doing so. But thanks to Ruby on Rails, he doesn't have to! So he said that he has no particular opinion about the Ruby programming language, but he absolutely loves Rails. The vast majority of programmers are non-experts, like himself, and the largest gains in productivity for non-experts come from having a wide spectrum of easy-to-use libraries. Subtle language features like first-class functions, and object systems, are lost on them because they don't really use them anyway. Computer scientists should really be spending their time developing new libraries rather than inventing new programming languages.My friend's opinion about programming languages is a common one, and I have heard it repeatedly from experts and non-experts alike. Being a language designer myself, I, of course, don't share this opinion. Here is what I consider to be the purpose of a general-purpose programming language.To start off, I would say that my friend's opinion is completely correct, just incomplete. The greatest productivity gains are indeed the result of having a wide spectrum of libraries. Ruby on Rails is a fantastic framework, and it has enabled thousands (if not millions) of non-experts to build sophisticated websites quickly. So the natura...