in reply to Re^3: foreach vs while<>
in thread foreach vs while<>

One this is for certain is that there is no reason to do @a = <$fh>; for (@a) unless you do something else with @a.
That's not true. There's an advantage
@a = <$fh>; for (@a) { .. }
gives you which
while (<$fh>) { .. }
doesn't give you which may be useful sometimes. Doing @a = <$fh> means you're done reading the file before processing it. If you have a lock on the file, you can then release it. But if you are doing
while (<$fh>) { .. }
you're only done reading the file after you've processed almost everything (and one typically releases a lock after processing everything). Now, most of the time, this doesn't matter because noone else needs the file (so you don't have locks, and the file doesn't get modified), or the processing goes fast (so there isn't much difference).

But it goes to far to say "there's no reason to do @a = <$fh>; for (@a)". Sometimes, there is.

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Re^5: foreach vs while<>
by ikegami (Patriarch) on Nov 12, 2008 at 17:31 UTC

    If you have a lock on the file, you can then release it.

    I had considered that possibility. That would be

    @a = <$fh>; close $fh; for (@a) { .. }

    There are reasons to load the file into an array. That's one of them, and I listed four others. But that's not the code the OP posted, and that's not the code I proclaimed should be avoided. You did not contradict me, or do you think I've already contradicted myself four times?

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