word boundary match problem

martymart has asked for the wisdom of the Perl Monks concerning the following question:

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Re: word boundary match problem by Mr. Muskrat (Canon) on Jun 23, 2003 at 16:21 UTC
Change the first while to a foreach and remove the angle brackets from around @source and it'll work. `#!/usr/bin/perl -w use strict; open (SOURCE, '<', 'test.txt') \|\| die "Can't open test.txt: $!"; my @source = <SOURCE>; close (SOURCE); my $size=0; foreach(@source){ $size++ while m{\b\w+\b}g; } print "wordcount: $size words\n";` [download]	[reply] [d/l]
Re: word boundary match problem by BrowserUk (Patriarch) on Jun 23, 2003 at 16:25 UTC
The problem is that you're not counting the words in the file you're ... um.. To be honest, I'm not quite sure what you are counting. 171 seems to big a value for you to be counting the number of words in the filenames of files in the current directory whos names match one of the lines in your datafile, but I think that is what you are doing. The problem is this line `while(<@source>){`. This isn't iterating over the array @source! It is supplying the contents of @source to the diamond operator <>, which in this context performs a glob on each of its arguments against the current working directory. And you are counting the results of this glob? The number still seems to high ... but whatever. To make your program work you could change to `#!/usr/bin/perl use strict; open (SOURCE, "test.txt")\|\|die "Can't open test.txt: $!"; my @source=<SOURCE>; close (SOURCE); my $size=0; for( @source ){ $size++ while m{\b\w+\b}g; } print "wordcount: $size words\n";` [download] There are several better ways to count words in files, but that should get you going. Examine what is said, not who speaks. "Efficiency is intelligent laziness." -David Dunham "When I'm working on a problem, I never think about beauty. I think only how to solve the problem. But when I have finished, if the solution is not beautiful, I know it is wrong." -Richard Buckminster Fuller	[reply] [d/l] [select]
Re: Re: word boundary match problem by gellyfish (Monsignor) on Jun 23, 2003 at 16:33 UTC
I'm not quite sure what you are counting. 171 seems to big a value for you to be counting the number of words in the filenames of files in the current directory whos names match one of the lines in your datafile, but I think that is what you are doing. glob returns the literal pattern when there isn't a match, which in this case will be the lines of the file. /J\	[reply]
Re: word boundary match problem by gellyfish (Monsignor) on Jun 23, 2003 at 16:25 UTC
I'm surprised this works at all - it certainly isn't doing what you think it is. The : `while(<@source>) { ... }` [download] is actually doing a glob based on the contents of the file and is making $_ the actual line where (not unexpectedly) there isn't a match. I think you meant: `foreach ( @source ) { ... }` [download] or `while(<SOURCE>) { ... }` [download] if the latter you will need to move the `close` to after the loop. /J\	[reply] [d/l] [select]
Re: word boundary match problem by Zaxo (Archbishop) on Jun 23, 2003 at 16:25 UTC
Your inner while isn't doing what you want, and the outer one is badly formed. You have set up @source so that for is the loop you want. Match in list context will count the words on a line, so this will do: `my $size = 0; for (@source) { $size += () = m{\b\w+\b}g; }` [download] After Compline, Zaxo	[reply] [d/l]
Re: word boundary match problem by Tomte (Priest) on Jun 23, 2003 at 16:28 UTC
Funny, with my little test.txt, it counts to much words, due to umlauts... :) I'd modifie the line inside the loop as `$size++,print "-".$1."-" while m{\b(\w+)\b}g;` [download] to see where it fails. regards, tomte Hlade's Law: If you have a difficult task, give it to a lazy person -- they will find an easier way to do it.	[reply] [d/l]