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>>[Ongoing discussion of Turing loop structure]

In article <12@euteal.UUCP> mart@euteal.UUCP (Mart van Stiphout) writes:
>[ C's "do", "for", "while" vs. "loop" structring ]
>[What about the following 1.5 loop?]
> while ( i = read() )   { ... code .... }

The above C fragment lets you put only restricted kinds of code inside
the `while' condition (a 1.25 loop?).

There is a more general construct that I've not seen in any existing
programming languages, although (a) doubtless it exists and (b) the
idea is easily a decade old (ok, probably 30, but I *know* at least
10) Substitute your favorite C/Pascal/Lisp/Smalltalk syntax.  In
meta-Algol:

	do ... while boolean ... od;


The conventional "while" loop looks like:

	do while (condition)
	    ...
	od;

The "repeat until" looks like:

	do
	    ...
	while (condition) od;

A single-exit 1.5 loop (most of my 1.5 loops are single exit) looks
like:

	do
	    ...
	while (condition)
	    ...
	od;

The multi-exit 1.5 loop is still less structured.

	;-D on  ( Do ... while ... crazy ... )  Pardo
-- 
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