Re: while(){}continue{}; Useful?

For an example usage, consider -p.

$ perl -MO=Deparse -pe'f()'
LINE: while (defined($_ = <ARGV>)) {
    f();
}
continue {
    die "-p destination: $!\n" unless print $_;
}
-e syntax OK
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It's just a question of pref, I think. It's also has a parallel with for(;;). Scoping aside,

for (A; B; C) {
   D;
}
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is basically the same as

A;
while (B) {
   D;
} continue {
   C;
}
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I've never used continue.

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Re^2: while(){}continue{}; Useful? by DStaal (Chaplain) on Mar 03, 2010 at 22:01 UTC
I use it a fair amount, mostly for your last example type situation, when the 'C' code is more complex than a single line. I find it easier to read to keep the 'loop maintenance' and 'loop actions' code separate. My most common example is probably a user-input loop: 'B' is while I can read from the input, and 'C' is the prompt/menu. (This assumes an interactive-only program, of course.) 'D' is the actual code to handle the different choices. Yes, that could be put in the loop in most/all cases, but I like knowing where to look for each type of code, and that they won't interfere with each other.	[reply]

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Re^2: while(){}continue{}; Useful?
by DStaal (Chaplain) on Mar 03, 2010 at 22:01 UTC

I use it a fair amount, mostly for your last example type situation, when the 'C' code is more complex than a single line. I find it easier to read to keep the 'loop maintenance' and 'loop actions' code separate.

My most common example is probably a user-input loop: 'B' is while I can read from the input, and 'C' is the prompt/menu. (This assumes an interactive-only program, of course.) 'D' is the actual code to handle the different choices.

Yes, that could be put in the loop in most/all cases, but I like knowing where to look for each type of code, and that they won't interfere with each other.

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