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Re: fast string parser: regex versus substr

by mce (Curate)
on Nov 20, 2003 at 16:55 UTC ( [id://308622]=note: print w/replies, xml ) Need Help??


in reply to fast string parser: regex versus substr

Thanks all,

I came up with.

sub dopack { foreach my $i ( 0..$#data ) { my $line=$data[$i]; my ($jcpu,$j,$s)=(unpack('@2A16A40A232A16', $line))[0,1,3]; warn "$jcpu $j $s"; # ..store the values in a hash, but that is not important here } }
And it won the benchmark competition :-)

I never really understood pack and unpack, but it am getting to like it.
---------------------------
Dr. Mark Ceulemans
Senior Consultant
BMC, Belgium

Replies are listed 'Best First'.
Re: Re: fast string parser: regex versus substr
by bart (Canon) on Nov 20, 2003 at 22:24 UTC
    my ($jcpu,$j,$s)=(unpack('@2A16A40A232A16', $line))[0,1,3];
    I think you'd be better off using the "x" template to ignore the third field (with index 2):
    my ($jcpu,$j,$s)= unpack('@2A16A40x232A16', $line);

    You can replace the leading '@2' with 'x2'', too. Or, just the reverse, replace the 'x232' with '@290'. I don't think it'll make much difference speedwise.

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