How do I count the characters, words, and lines in a file, using Perl?

Question

What is a good/best way to count the number of characters, words, and lines of a text file using Perl (without using wc)?

Answer 1

Here's the perl code. Counting words can be somewhat subjective, but I just say it's any string of characters that isn't whitespace.

open(FILE, "<file.txt") or die "Could not open file: $!";

my ($lines, $words, $chars) = (0,0,0);

while (<FILE>) {
    $lines++;
    $chars += length($_);
    $words += scalar(split(/\s+/, $_));
}

print("lines=$lines words=$words chars=$chars\n");

Answer 2

A variation on bmdhacks' answer that will probably produce better results is to use \s+ (or even better \W+) as the delimiter. Consider the string "The  quick  brown fox" (additional spaces if it's not obvious). Using a delimiter of a single whitespace character will give a word count of six not four. So, try:

open(FILE, "<file.txt") or die "Could not open file: $!";

my ($lines, $words, $chars) = (0,0,0);

while (<FILE>) {
    $lines++;
    $chars += length($_);
    $words += scalar(split(/\W+/, $_));
}

print("lines=$lines words=$words chars=$chars\n");

Using \W+ as the delimiter will stop punctuation (amongst other things) from counting as words.