PEP 315: Enhanced While Loop

[Dan Bishop]

"Ben Allfree" <benles at bldigital.com> wrote in message news:<mailman.1051973585.3998.python-list at python.org>...
...
> At one point, quite a few BASIC and Pascal flavors had a repeat..until
> or do..while loop construct. It seems that it faded away, and I'm not sure 
> why.

Repeat...until is part of Standard Pascal, but hardly anyone uses
Pascal anymore.

For BASIC, the only flavor I've seen that had a posttest loop
construct (other than conditional GOTO) was QBasic, which had a
DO...LOOP block that allowed all 4 possible combinations of
pretest/posttest and WHILE/UNTIL, so your code could have been written

' option 1: pretest WHILE
' This could also be done by the older WHILE...WEND construct
MakeMoney
DO WHILE Poor()
   MakeMoney
LOOP

' option 2: pretest UNTIL
MakeMoney
DO UNTIL NOT Poor()
   MakeMoney
LOOP

' option 3: posttest WHILE
DO
   MakeMoney
LOOP WHILE Poor()

' option 4: posttest UNTIL
DO
   MakeMoney
LOOP UNTIL NOT Poor()

While this was a good syntax for a language that delimited blocks with
pairs of statements (e.g., FOR...NEXT, FUNCTION...END FUNCTION),
unfortunately it wouldn't work well in Python.

Personally, I'm satisfied with

while True:
   MakeMoney()
   if not Poor():
      break