On Mon, 2009-10-12, Grant Edwards wrote:
> On 2009-10-12, Gabriel Genellina <gagsl-...@yahoo.com.ar> wrote:
>
>>> my_prissy_little_indicator_variable = true
>>> while (my_prissy_little_indicator_variable){
>>> <body>
>>> }
>>> isn't satisfying because it doesn't guard the <body> with any
>>> assurance that the loop invariant will be true before you enter into
>>> that block of code.
>>
>> I think you meant the other way; the above is the simplest loop case, with
>> the test at the start.
>
> Except the test at the start is meaningless when it comes to
> reading the code and troubleshooting. What counts are
> assignments to my_prissy_little_indicator_variable inside the
> loop. And those aren't really any easier to spot that "break"
> statements.
It's a red herring. A good loop tends to *not* have a boolean
variable as the while ... expression. That smells like flag
programming, and if I cannot come up with anything better that that, I
often prefer a "while 1" with breaks in it.
For a real-life loop, see for example
http://en.wikipedia.org/wiki/Binary_search#Iterative
(except it confuses me because it's a repeat ... until and it's in
Pascal with that quaint 1-based indexing)
/Jorgen
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// Jorgen Grahn <grahn@ Oo o. . .
\X/ snipabacken.se> O o .
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