Type checking is a symptom, not a solution

All programmers need to try assembly programming just once.

Just a program counter, a stack, a flat addressable block of memory, and some registers.

You’ll very quickly learn how hard it is to program when you have complete responsibility for making sure that the state of the system is exactly as expected before a routine is called, and that it’s restored on return.

Every language tool we’ve built on top of that is to help programmers keep track of what data they stored where, what state things should be in before particular bits of code are run, and making it harder to make dumb mistakes like running some code that will only work on data of one sort on data of a totally different structure.

Of course types are a solution. You just have no idea what the problem was.

When I was taking my compilers class at uni, I realised very quickly that the most irritating part was the sheer volume of book-keeping.

Things like the ABI itself, which includes register saving/restore, function call stack setup, to the linker and loader, ensuring the right sections go to the right places and are correctly sized, and then at load time ensuring relative addresses are correctly relocated, all branch target labels are resolved to these relocated addresses, it was such a pain.

All of this book-keeping was a genuinely the most time-consuming part of the assignments; the actual compiler ideas and implementation being relatively manageable.

Funnily enough the compiler implementation was done in OCaml.