static_assert for compile-time assertions

[michaeljklein]

Problem

Add a builtin function static_assert, that behaves like assert, but runs at compile time when encountered in monomorphization.

Happy Case

It should:

• Only succeed on constant data (similarly to the generic arithmetic prototype here)
• Run the interpreter to try and evaluate to a boolean literal
• Fail unless that boolean is true

Project Impact

Nice-to-have

Impact Context

This will allow working around our lack of arithmetic generics:

fn tail<T, N, M>(xs: [T; N]) -> [T; M] {
  static_assert(N - 1 == M);
  ..
}

fn main() {
  assert(tail<Field, 3, 2>([1,2,3]) == [2, 3]);
}

Workaround

None

Workaround Description

Currently the issue can be worked around by using run-time assertions and collecting all of them at the top of main().
Additionally, a separate binary could be built with only the assertions collected from the program.

Additional Context

No response

Would you like to submit a PR for this Issue?

None

Support Needs

No response