Re: Pulling lines from file, noob style

Obviously, since you only showed 1 line of your input, this is just a guess, but perhaps you really want to only print if the regex matches, something like this:

while( <SMRT> ){
        chomp ();
        if (/Power_On_Hours(.*)/i) {
            $hours = $1 ;
            @time = split(' ',$hours);
            print "Power on hours = $time[7]\n";
        }
}
[download]

Also, use strict and warnings, as they would probably have given you some useful debugging information in this case.

Comment on Re: Pulling lines from file, noob style Download Code

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Re^2: Pulling lines from file, noob style by jperkins (Initiate) on Feb 17, 2010 at 17:33 UTC
Yes! That did it! It looks like I closed that expression early than? Is that why it picked up more than what I asked?	[reply]
Re^3: Pulling lines from file, noob style by xyzzy (Pilgrim) on Feb 17, 2010 at 17:43 UTC
It picked up exactly what you asked, but it printed even when it didn't pick anything up. as you use Perl, your mind will assimilate to a more perlish way of procedural thinking. for instance, the same snippet could be written as `while( <SMRT> ){ chomp; next unless /Power_On_Hours(.*)/i; $hours = $1; @time = split(' ',$hours); print "Power on hours = $time[7]\n"; }` [download] although the overall effect is the same as using an if statement the intention is more explicit: you don't care about the line unless it matches the regex. as perl takes over you mind, you should notice a decrease in errors of this sort `$,=qq.\n.;print q.\/\/____\/.,q./\ \ / / \\.,q. /_/__.,q..` Happy, sober, smart: pick two.	[reply] [d/l] [select]
Re^4: Pulling lines from file, noob style by johngg (Canon) on Feb 17, 2010 at 22:56 UTC
Definitely more perlish, but why waste cpu clicks `chomp`ing lines that might be rejected? I'd move the `chomp` line to be immediately after the `next unless ...` line. I'd perhaps even question whether chomp was necessary here as the dot in the regex will not match the line terminator. `J:\johngg>i:\cygwin\bin\hexdump.exe -C test.txt 00000000 61 61 61 61 61 31 32 33 0d 0a \|aaaaa123. +.\| 0000000a J:\johngg>perl -nle "next unless /^a+(.*)/; print qq{>$1<};" test.txt >123<` [download] I hope this is of interest. Cheers, JohnGG	[reply] [d/l] [select]