From: WC -Sx- Jones <[EMAIL PROTECTED]>
> Hanson, Rob wrote:
> >>Is there a way to determine the number of lines
> >>in a file without actually iterating through the
> >>file and incrementing a file?
> >
> >
>
>
> # No silver bullet; but shorter -
>
> undef $/; # Slurp;
>
> foreach $target (@ARGV) {
> @lines = ();
>
> open (HTML_FILE, "<$target") or die "owie";
> @lines = split(/\n/, <HTML_FILE>);
>
> print "In $target - Seen: ". ($#lines + 1) ." lines...\n";
> }
>
> __END__
Rather inefficient.
First you slurp the file and then you split it? Why?
You could do it like this instead :
foreach $target (@ARGV) {
open (HTML_FILE, "<$target") or die "owie";
my @lines = <HTML_FILE>;
print "In $target - Seen: ". scalar(@lines) ." lines...\n";
}
Even shorter, slightly more efficient, but still very memory hungry.
(The scalar() is not necessary, thanks to the dots @lines would be in
scalar context anyway. And since the @lines is lexicalized into the
loop I do not have to explicitely clear it.)
Since you don't actually need the lines you might also do it like
this:
foreach $target (@ARGV) {
open (HTML_FILE, "<$target") or die "owie";
() = <HTML_FILE>;
print "In $target - Seen: ". $. ." lines...\n";
}
I'd be worried though that Perl might load the whole file and
construct the list anyway so I'd rather use
foreach $target (@ARGV) {
open (HTML_FILE, "<$target") or die "owie";
1 while <HTML_FILE>;
print "In $target - Seen: ". $. ." lines...\n";
}
Jenda
===== [EMAIL PROTECTED] === http://Jenda.Krynicky.cz =====
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