Breaking out of several nested loops (& ANSI C)

[Doug Gwyn <gwyn>]

Gee, I thought everyone knew that the most general structured loop is
	startloop
		...
		on condition (...) leaveloop
		...
	repeatloop
which can mimic a "while" or "do .. while" loop if one or the other
of the body sections is null.  The rules for "structuredness" seem
to be: a loop invariant is being maintained (and is stated EXPLICITLY,
perhaps in a comment), the loop is entered at the top, and there is
only one exit from the loop.  C's "break" and "continue" violate this
just as much as a "goto" would.  But so what; a conscientious
program designer will "think structured" no matter what language he
is using.  I have yet to see an automated tool (including ADA) for
enforcing proper programming practice that can compensate for ignorance
or stupidity on the part of its user.