Is there an explanation, why split() behaves like this:

# a simple tokenizer
$ perl -e 'print join("|",split(/(\W)/,"Hello, World! ?")),"\n";'
Hello|,|| |World|!|| ||?

# get rid of the empty string tokens
$ perl -e 'print join("|",grep {$_}split(/(\W)/,"Hello, World! ?")),"\
+n";'
Hello|,| |World|!| |?

# or use plain regex
$ perl -e 'print join("|","Hello, World! ?"=~/(\W|\w+)/g),"\n";'
Hello|,| |World|!| |?

[download]

TIA

Helmut Wollmersdorfer

In reply to Empty strings after split /(\W)/ by wollmers

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