I'd prefer while (1) { ... } to for (;;) { ... }. Looks easier to understand to me.

There's one significant advantage (from the reader's point of view) to while (1):

• The meaning of while (1) is straightforward to deduce by someone who has never seen it, whereas the meaning of for (;;) is not.

There are minor advantages (from the reader's point of view) to for (;;):

• for (;;) has no expression to read, while while (1) does. (Note the addition of loop { ... } in Perl 6.)

• "(;;)" can be read as "ever". "For ever" sounds better than "while one", "while true" or "while ever" (and requires no mental backtracking). "While not done" would be a great reading, but translating "1" to "not done" is a stretch.

• for (;;) is visually distinctive from naturally ending loops.

Update: hum... while (!0) could be read as "while not done"...

Well, we could write while (not 'done') { ... }, but even though it would work and it would read fine, I think it would actually confuse people ;-)

Update: while ('not done') { ... } of course. Sorry. I guess I should not be here at 1am. Thanks Sidhekin.

Jenda


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Don't know if/when this will get looked at but I was unaware that a do-while loop didn't operate like a loop so last doesn't "work" with it. My problem is I have a structure similar to this. I'm guessing what I need is a way to keep reading the next line in the file, but at times I had problems assigning $aVar = <AFile>. Would a similar loop construct with $aVar = <Afile> being the final statement in that bare loop work?

while(<AFile>)
{
if(found keyword)
do{
process keyword and next few lines
if(done processing){
last
}
}while(<AFile>);
# do some post processing
}

# Continue processing after this in the same file
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