I'm writing a bit to look for palindromes. To search for those with embedded whitespace, like "God dog" I started with this regex: 

    /(\b([a-zA-Z]).*$2\b)/i;

[download]
But it matches any line. For instance: 
   Being able to script this in Perl gives a lot more flexibility, and
   is arguably easier to use and extend.
I'm blind as to where the $2 match is occuring in those two lines. There is no word ending in b on the first line. There is no word ending in i on the second.

What is the problem with my perception of the regex?

update: OP used <pre> instead of <code> tags. This confused the issue for the first few replies. Question was really and completely addressed by japhy - I was asking for the smack upside the head to clear out temporary blindness.

Be Appropriate && Follow Your Curiosity

In reply to regex at word boundary by mikeraz

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
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