in reply to about split

I think the confusion here is that "split" is not the same as "split / /". Rather, "split" is the same as "split /\s+/".

Also, if you "split $_", Perl thinks you're using $_ as your pattern. You can't leave out the pattern and still pass a string to split. If you specify a string, you also have to specify a pattern.

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Re^2: about split
by BrowserUk (Patriarch) on Mar 12, 2008 at 16:22 UTC
    Rather, "split" is the same as "split /\s+/"

    Actually, it's not. The only way to avail yourself of the magical default split whilst processing other than $_, is to use ' ' or " " in place of the regex. See the first and last examples below: 

    C:\test>p1
$_ = '   the quick    brown fox   ';;

print join'|', split;;   ## default split no args (leading null field 
+omitted)
the|quick|brown|fox

print join'|', split /\s+/;; ## \s+ includes leading null field
|the|quick|brown|fox

print join'|', split / /;; ## same as split /\s/
|||the|quick||||brown|fox

print join'|', split ' ';; ## Same as no arg split
the|quick|brown|fox

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Re^2: about split
by Not_a_Number (Prior) on Mar 12, 2008 at 16:21 UTC
    "split" is the same as "split /\s+/".

    Not quite the same:

    no warnings 'uninitialized';
$_ = '  a string with leading whitespace';
print join( ':', split ), "\n";  
print join( ':', split /\s+/ ), "\n";
______
a:string:with:leading:whitespace
:a:string:with:leading:whitespace

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