Beefy Boxes and Bandwidth Generously Provided by pair Networks
Keep It Simple, Stupid

Re: Counting words

by fruiture (Curate)
on Aug 23, 2002 at 23:03 UTC ( #192473=note: print w/replies, xml ) Need Help??

in reply to Counting words

There are 2 errors in your code: a syntax error '$pattern = \b\w+\b;' and a logical one. Try this:

my ($count,$pattern,$file) = ( 0 , qr{\b\w+\b} , shift ); # declares and initializes the three variables # see perlop for qr// open FILE,$input or die "Error: $!"; # please read `perldoc -q 'quoting.*vars'` while(<FILE>){ $count += () = /$pattern/g; # that's kind of an idiom for counting the matches # it forces list context on m//g, but forces scalar # context on the resulting empty(?) list # that returns the number of elements that were # assigned to the list, although # in the end it's all thrown away, never reaching any # accessible memory outside the perl-internals... # -- it counts the number of matches } close FILE;


UPDATE: yes, qr// instead of qx//, i mixed 'em up, because i don't often use qr//. Thanks to sauoq and wog


Replies are listed 'Best First'.
Re: Re: Counting words
by PodMaster (Abbot) on Aug 24, 2002 at 11:48 UTC
     $count += () ... kind of an idiom

    I've always hated that idiom. It's so satanic.

    #!/usr/bin/perl use strict; use warnings; my $COUNT = 0; while(<DATA>){ $COUNT++ while m{\b\w+\b}g; } die "COUNT $COUNT"; __END__ Hello there boss! How are you doing today. I really hope you don't slip on that banana peel. I count 22 words.

    ** The Third rule of perl club is a statement of fact: pod is sexy.

Re: Re: Counting words
by wog (Curate) on Aug 24, 2002 at 05:27 UTC

    I think fruiture meant to write qr instead of qx. ("Quote Regex" as opposed to "Quote eXecute". Of course checking perlop, as reccommended, would hopefully let one fiquire this out...)

Log In?

What's my password?
Create A New User
Domain Nodelet?
Node Status?
node history
Node Type: note [id://192473]
and the web crawler heard nothing...

How do I use this? | Other CB clients
Other Users?
Others examining the Monastery: (5)
As of 2022-12-02 16:06 GMT
Find Nodes?
    Voting Booth?