primitive-recursive

Implementation of primitive recursive functions using C++20 constexpr variadic template lambdas ;)

Basis of primitive recursive functions:

• Z (zero)
• N (increment)
• U (projection)
• S (composition)
• R (primitive recursion)

Implemented examples:

1. addition, multiplication, subtraction
2. less or equal predicate
3. factorial
4. div, mod
5. sqrt
6. pair -> number in diagonal numbering