why no "do : until"?

[Martijn Faassen]

Peter Hansen <peter at engcorp.com> wrote:
[snip]
> I suspect some of us would even argue that the conditional in 'do/until'
> can be difficult for some people to get right and that forcing the use of
> 'while/if/break' may actually increase the likelihood the resulting code
> will be correct the first time, and be interpreted correctly during
> maintenance.  My guess is that for this precise reason the alternative
> loop construct was removed from/never added to Python in the first place.

I suspect (and seem to recall hearing about this before) the reason is
more prosaic; how does one indent the darn thing? :)

do:
   ..
until x > 25

does not fit a pythonic pattern for statements.

do:
   ..
   until x > 25

doesn't either, unless 'until' is a new statement. But to fit the Python
pattern, it'd need to be usable at least anywhere within the loop, and
in that case it's just a synonym for:

   if x > 25: break

which we already have.

Regards,

Martijn
-- 
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