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A couple of things. First and foremost, don't you think that ought to be:

my $slurp = join $/, <FH>;

Otherwise you can't really distinguish between lines. Next, you're having perl read the file in, split the file on $/, and then rejoin everything and you end up with a string that was exactly what it was before the split. If you just localize $/ and then read the file in, you're done. Of course, I have some nice benchmarks that show the local $/ method to be a little under 5 times faster. As with any other benchmarks, YMMV.

#!/usr/bin/perl -w use Benchmark qw(cmpthese); # file.txt is about 2200 lines each between 5 and 50 chars long open FH, "file.txt" or die $!; sub scalarcon { seek(FH,0,0); local $/; <FH>; } sub listjoin { seek(FH,0,0); join '',<FH>; } cmpthese(-5,{scalarcon=>\&scalarcon,listjoin=>\&listjoin}); __DATA__ Benchmark: running listjoin, scalarcon for at least 5 CPU seconds... listjoin: 5 wallclock secs ( 5.25 usr + 0.12 sys = 5.38 CPU) @ 30 +.70/s (n=165) scalarcon: 6 wallclock secs ( 1.95 usr + 3.36 sys = 5.30 CPU) @ 15 +3.26/s (n=813) Rate listjoin scalarcon listjoin 30.7/s -- -80% scalarcon 153/s 399% --

Update: As chromatic has pointed out, I'm a twit.

Hope this helps.

antirice    
The first rule of Perl club is - use Perl
The
ith rule of Perl club is - follow rule i - 1 for i > 1


In reply to Re: Re: Perl Idioms Explained - my $string = do { local $/; <FILEHANDLE> }; by antirice
in thread Perl Idioms Explained - my $string = do { local $/; <FILEHANDLE> }; by jeffa

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