Keystone,

I am relatively new here at perlmonks, but perhaps I can help a little bit.

You asked why the regexp matched only once, instead of multiple times. This is so because it is a FEATURE of the rules of regex to only do so unless something like the "global" switch is added *at the end of the regex in play*.

If you invoke the global switch, then all matches will be replaced with the substitution string.

So, if you had some code: 

$_="FourThreeTwoOne, Three, Four, One, Two";
$1="Three";
$second="&&&&";
s/$2/$second/g;
print;

it would print this result:

Four&&&&TwoOne, &&&&, Four, One, Two

Hope this helps.

-HaT

In reply to Re^3: RegExp substitution by HereandThere
in thread RegExp substitution by Keystone

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