Comment by Someone

An alternative way to look at for C/C++/pascal/… programmers it is by looking at the return keyword not as a keyword, but as an implicit argument that’s a pointer to a function. Imagine this would work:

   global fooBack
   global barBack
   main() {
     print foo()
   }
   foo() {
     fooback = return
     bar()
     return “foo”
   }
   bar() {
     barBack = return
     if randomBool
       fooBack(“bar”)
     else
       return “bar”
   }

and that, 50% of the time, woud print “bar”.

In a C-like system with a call stack, that would give you a nicer setjmp (still with quite a few limitations). Systems with true continuations would allow code to call ‘up the stack’ for example if main were to call barBack in the scenario above. That wouldn’t work in C as bar’s stack frame wouldn’t exist anymore.