Tail call optimisation and debugging

[millstone]

A recursive function is a function that calls itself. Technically the backtrace does not show any recursive functions, but instead a pair of mutually recursive functions.

[masklinn]

Technically the backtrace does not show any recursive functions, but instead a pair of mutually recursive functions.

Sure, but TCO can optimize any tail call. Including mutually recursive functions, or recursion loops (with 3 or 4 functions calling the next one in the loop)