Re^2: performance issues

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Re^3: performance issues by gone2015 (Deacon) on Jan 27, 2009 at 23:23 UTC
OK. From what I've understood you to want... see if something along these lines works any better: `use strict ; use warnings ; my $data ; { local $/ ; $data = <DATA> ; } ; my $s = 'bc' ; # Substring to search for in left hand side my @r = ($data =~ m/$s[^\s][ \t]+(.)/g) ; print "@r\n" ; __DATA__ abcd s1 efgh s2 ijklm s3 nopq s4 bc s5 aqbc s6 rst s7 uvwx s8 yz s9` [download] noting that the `[ \t]+` can be changed to simply `\t` for use with your file (I've used `[ \t]+` here only because that works even if the stuff between the "blocks" has been converted to any mixture tabs and spaces). Noting also that the `(.)` will stop at end of line. Note also that this is assuming that the right hand side will not contain any tabs (or spaces) The regex can match to the search substring in the right hand side, but since that ends in a newline, the `[^\s][ \t]+` part will fail the match. The following: `my $data = "\n" ; { local $/ ; $data .= <DATA> ; } ; my $s = 'bc' ; # Substring to search for in left hand side my @r = ($data =~ m/\n.?$s[^\s][ \t]+(.*)/g) ;` [download] avoids matching in the right hand side, and the right hand side can contain tabs (and spaces). I don't have enough data to know if there's any performance advantage or disadvantage here.	[reply] [d/l] [select]
Re^4: performance issues by perlcat (Novice) on Jan 28, 2009 at 07:54 UTC
thank you I will test the code this weekend and see if it runs any faster.	[reply]
Re^3: performance issues by JadeNB (Chaplain) on Jan 27, 2009 at 22:19 UTC
I'm using m=~ to achieve this. I guess that this is a typo—if you've got working code at all, then you must be using something like (if we must call it that) `=~m//`, not `m=~`.	[reply] [d/l] [select]