in reply to Re: Re: Re: split/map weirdness: empty strings vs undef
in thread split/map weirdness: empty strings vs undef

Uhm... split(/\|/, "2|3||||"); is different from split('|', "2|3||||"); only because that pipe isn't escaped in the second one. Perl will split on that as if it were a pattern. In other words, that's broken in the same way as your original one. Note that splitting on a literal space is a special case. This isn't.

$ perl -le '$_="2|3|||||"; @a = split q(|); print "($_)" for @a'
(2)
(|)
(3)
(|)
(|)
(|)
(|)
(|)

$ perl -le '$_="2|3|||||"; @a = split /|/; print "($_)" for @a'
(2)
(|)
(3)
(|)
(|)
(|)
(|)
(|)

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-sauoq
"My two cents aren't worth a dime.";

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Re: Re: Re: Re: Re: split/map weirdness: empty strings vs undef
by dws (Chancellor) on Oct 04, 2002 at 21:39 UTC 
    print "($_)\n" for split(/\|/, "2|3|||||");
__END__
(2)
(3)

print "($_)\n" for split('|', "2|3|||||");
__END__
(2)
(|)
(3)
(|)
(|)
(|)
(|)
(|)

C:\> perl -v
This is perl, v5.6.1 built for MSWin32-x86-multi-thread
(with 1 registered patch, see perl -V for more detail)

Copyright 1987-2001, Larry Wall

Binary build 631 provided by ActiveState Tool Corp. http://www.ActiveS
+tate.com
Built 17:16:22 Jan  2 2002

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[d/l]

      Yes. That's exactly my point. My examples showed that /|/ and '|' were the same. For completeness: 

      $string = "2|3||";

print "Backwhacked bar in pattern: ";
print "($_)" for split /\|/, $string; print "\n";
print "Backwhacked bar in quotes:  ";
print "($_)" for split '\|', $string;  print "\n";
print "Just a bar in pattern:      ";
print "($_)" for split /|/, $string;  print "\n";
print "Just a bar in quotes:       ";
print "($_)" for split '|', $string;  print "\n";
__END__
Backwhacked bar in pattern: (2)(3)
Backwhacked bar in quotes:  (2)(3)
Just a bar in pattern:      (2)(|)(3)(|)(|)
Just a bar in quotes:       (2)(|)(3)(|)(|)

      [download]

      The presence of bars in the output of both splitting on '|' and on /|/ is because those are both really splitting on the null pattern. The quoted bar is not preserving fields.

      -sauoq
"My two cents aren't worth a dime.";
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[d/l]

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