What have you tried? What didn't work? See How do I post a question effectively?. Also, your node title is not very useful. See How do I compose an effective node title?. In particular, monks tend not to respond well to posts containing exclamation points.

As described in perlretut (the regular expressions tutorial), you can use the character class \s to test for white space. As well, as long as you don't use the x modifier (for in lining comments), you can just use a space character in your code. In your case, however it's probably easier to test for characters that are not whitespace using \S: 

for ("Hello", "   ", " x "  ) {
   print /\S/ ? "'$_': Fail\n" : "'$_': Pass\n";
}

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In reply to Re: Regular Expression Help! by kennethk
in thread Regular Expression Help! by Anonymous Monk

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