gap> f := function() local x; x := f(); return x; end;
function(  ) ... end
gap> y := f();
Error, recursion depth trap (5000) in
  f(  ) at *stdin*:2 called from 
f(  ) at *stdin*:2 called from
f(  ) at *stdin*:2 called from
f(  ) at *stdin*:2 called from
f(  ) at *stdin*:2 called from
f(  ) at *stdin*:2 called from
...  at *stdin*:3
you may 'return;'
brk> QUIT;
