Perl split array

Question

I'm new in Perl, I want to write a simple program which reads an input-file and count the letters of this file, this is my code:

 #!/usr/bin/perl

 $textfile = "example.txt";
 open(FILE, "< $textfile");

 @array = split(//,<FILE>);
 $counter = 0;
 foreach(@array){
      $counter = $counter + 1;
 }

 print "Letters: $counter";

this code shows me the number of letters, but only for the first paragraph of my Input-File, it doesn't work for more than one paragraph, can anyone help me, i don't know the problem =( thank you

ikegami · Accepted Answer · 2014-05-05 13:50:43Z

2

You only ever read one line.
You count bytes (for which you could use -s), not letters.

Fix:

my $count = 0;
while (<>) {
   $count += () = /\pL/g;
}

answered May 5, 2014 at 13:50

ikegami

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2 Comments

steke Over a year ago

hm, I replaced the foreach-loop, with the while(<>) {$count += () ...... - loop, doesn't work, don't show me anything

pilcrow Over a year ago

@user3340823, in your case it'd be while (<FILE>) ...

Dave Cross · Accepted Answer · 2014-05-06 09:52:25Z

1

You code is a rather over-complicated way of doing this:

#!/usr/bin/perl

# Always use these
use strict;
use warnings;

# Define variables with my
my $textfile = "example.txt";
# Lexical filehandle, three-argument open
# Check return from open, give sensible error
open(my $file, '<', $textfile) or die "Can't open $textfile: $!"

# No need for an array.
my $counter = length <$file>;

print "Letters: $counter";

But, as others have pointed out, you're counting bytes not characters. If your file is in ASCII or an 8-bit encoding, then you should be fine. Otherwise you should look at perluniintro.

answered May 6, 2014 at 9:52

Dave Cross

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Comments

lexu · Accepted Answer · 2014-05-05 15:03:42Z

-1

Here's an alternative aproach using a module to do the work ..

# the following two lines enforce 'clean' code
use strict;
use warnings;

# load some help (read_file)
use File::Slurp;

# load the file into the variable $text
my $text = read_file('example.txt');

#get rid of multiple whitespace and linefeed chars # ****
# and replace them with a single space             # ****
$text =~ s/\s+/ /;                                 # ****

# length gives you the length of the 'string' / scalar variable
print length($text);

you might want to comment out the lines marked '****' and play with the code...

edited May 5, 2014 at 15:03

answered May 5, 2014 at 14:58

lexu

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