Re: file substitution

I am not sure on performance, as I have not implemented something like this, but...

How about something like this....

...
my @junk = map {chomp $_; qr(\Q$_\E)} <JUNK>;
while (<>) {
    # Added / Modified
    my $line = $_;
    next if $line =~ $_ foreach (@junk);
    # End update
    print;
}
[download]

Order the junkfile in descending order of occurances.

Another option, to avoid the inner loop, would be to build a giant alternation regexp (qr((foo|bar|biz|bang))) from the junk file. However, then you need to escape various things. In addition, I am not sure which is faster, the alternation regexp or the nested loop.

--MidLifeXis

P.S. All code is untested, blah blah blah.

Update: Updated foreach stuff - Thanks BrowserUk. Added \Q..\E. Thanks Berik.

Comment on Re: file substitution Download Code

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Re^2: file substitution by BrowserUk (Patriarch) on Jun 04, 2004 at 18:56 UTC
This `foreach my $junk (@junk);` isn't valid perl syntax. If you want to name the control variable you have to use the `foreach my $name (@things) { #use $name }`, not the postfix form Examine what is said, not who speaks. "Efficiency is intelligent laziness." -David Dunham "Think for yourself!" - Abigail	[reply] [d/l] [select]
Re^2: file substitution by Berik (Sexton) on Jun 04, 2004 at 18:46 UTC
Be sure to use quotemeta or \Q..\E `my @junk = map {chomp $_; qr/\Q$_\E/} <JUNK>; while (<>) { next if $_ =~ $junk foreach my $junk (@junk); print; }` [download] perl's regexes are not as fast as grep's. But this will do, probably fast enough. --- Berik	[reply] [d/l]