What are the practical limitations of a non-turing complete language like Coq?

Question

As there are non-Turing complete languages out there, and given I didn\'t study Comp Sci at university, could someone explain something that a Turing-incomplete language (like C

Answer 1

An important class of problems that are a bad fit for languages such as Coq is those whose termination is conjectured or hard to prove. You can find plenty of examples in number theory, maybe the most famous is the Collatz conjecture

function collatz(n)
  while n > 1
    if n is odd then
      set n = 3n + 1
    else
      set n = n / 2
    endif
 endwhile

This limitation leads to have to express such problems in a less natural way in Coq.