How do I get a list of words, defined by white space, in a file and the number of times they appear. I realize that words like "book keeper" which can be spelled with or without a space, different case, and words that wrap lines are going to be an issue, but I want a 99% solution.

#!/usr/bin/perl
use strict;
use warnings;

my $file = $ARGV[0] || 'foo.txt';
open (INPUT, '<', $file) or die "Unable to open $file for reading : $!
+";

my %word;
while ( <INPUT> ) {
    chomp;
    $word{$_}++ for split " ";
}
print "$_ : $word{$_}\n" for sort { $word{$b} <=> $word{$a} } keys %wo
+rd;
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my $max_words = 8;

open F, "< d:\\temp\\perl\\test.txt" or die "Unable to open file\n";
undef $/;

$data = <F>;
@words = split /\W+/, $data;

print join ':', @words[0..$max_words - 1];
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use strict;

open (IN,"<in.txt") or die $!;
while (<IN>) {
    print "$1\n" if (/^\s*((?:[^\s]+\s+){4})/);
}
close(IN);
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I modified your code a little to fit the problem description slightly better:

use strict;

my $num_words = 4;

my @words = ();
open FILE, "<in.txt" or die $!;
while ( <FILE> )
{
        last if ( push ( @words, m/\s*([^\s]+)\s*/g ) >= $num_words );
}
close FILE;

print join( " ", @words ) . "\n";
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As a side note, is there a reason to use [^\s] rather than \S, or is it just a matter of preference? Thanks.

Zenon Zabinski | zdog | zdog@perlmonk.org

Yeah, "last if" is a good call, I wasn't thinking. The OP wasn't clear exactly how they wanted the results back (string or array of words), so I choose string. Nice convert to array though.

As far as [^\s] versus \S, force of habit. If my laziness virtue would kick in like its supposed to, I'd have switched to \S by now and saved some keystrokes :)

-jbWare

As you have a stream you probably want to use stream parsing logic. Here is an example:

my ( $space, $wc );
my $get_words = 5;

while( read(DATA,$_,1) ) {
    if ( m/\s/ ) {
        $space = 1;
    }
    else {
        if ( $space ) {
            print "\n";
            $space = 0;
            $wc++;
            last if $wc >= $get_words;
        }
        print;
    }
}
__DATA__
There  was   an 

old

lady who lived

in    a    shoe
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