in reply to Re: Regex help needed
in thread Regex help needed

"Technically" split requires a regular expression as its first argument. String patterns appear to be an undocumented extension.

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Re^3: Regex help needed
by JavaFan (Canon) on Apr 23, 2012 at 16:38 UTC
    Huh, what are you talking about? Using strings as patterns is fine. Remember, this is Perl. If Perl expects a pattern somewhere, whatever you put there is a pattern. What you call an "undocumented" extension is nothing different from: 
    $foo = "3";
$bar = 4 + $foo;

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    or even: 
    my $pattern = "foo|bar";
say "Match" if $str =~ $pattern;

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    In my snippet, '%' is pattern by virtue of it being the first argument of split, not because of some "undocumented extension".

    Note also this snippet from the split documentation: 

    As a special case, specifying a PATTERN of space (' ') will
split on white space just as "split" with no arguments does.
    Note how the documentation talks about a pattern, while using quotes to delimit said pattern.
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      But be careful, / / and ' ' are not the same thing for split:
      use feature 'say';
my $x = "a\tb\tc";
say for split ' ', $x;
say for split / /, $x;

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      your example 
      my $pattern = "foo|bar";
say "Match" if $str =~ $pattern;

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      is very convincing. - Sorry about that.
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