[gsliepen]

> defining C functions and for-loops are so much more verbose than just using JMP instructions in assembly language

Are you sure? It's not just a JMP; for a loop you need a compare and increment/decrement instruction at the very least, and calling a function is way more complex than a JMP: you have to place the function arguments in the right registers and/or on the right place on the stack, you need to save registers that might get clobbered, and you need to push a return address before you jump. So in C these things are definitely more compact to write.

I did get the point about effects introducing a new form of structure and composability, and I'd really like to see that. But at the moment it looks like it is as much work as actually implementing a function call in assembler, the only benefit is that the compiler will check the correctness for you.