- it's easy to prompt an LLM to do it for you, especially if you're targeting a pre-existing runtime like CLR or transpiling to another language. previously you'd have to grind out the parser and compiler for a new language, but a lot of that work is mechanical
- "I want a language that works a little differently"
- programming language theory (PLT), generally
- languages are tools. the authors should explain what their languages are best suited for
- Obj C and C++ were both developed around the same time as extensions of C. Obj C was focused on message passing and Smalltalk's object system, while C++ was focused on adding as many abstractions as possible to C. Neither language has good support for avoiding null pointer dereferences, one of the primary things Swift addresses with its richer type system and Optionals.