Another way to do away with #end/{/} may be to adopt a Python-like blocking
mechanism where the indentation level affects the block. Then a block as above
could simply be:
MyRing = union:
for(x=0,x<10,x=x+1):
circle:
<...>
....
One problem I've heard from critics of this system is that most editors can't
automatically detect and create folds.