Hello monks! I am parsing a webpage right now to make it 508 compliant. If an IMG tag has an alt element, I need to leave it alone but if it doesn't, it needs one added. Some of these IMG tags span a few lines and I have discovered that this works on tags that don't have alt ( Any options that change the document formatting like removing \n or \r are out for bureaucratic reasons )
$contents=~s!<IMG\s(.*?)>!<IMG $1 alt="text">!sig;

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What I am stumped on is how to pull the equivalent of this off.. 
$contents=~s!<IMG\s(.*?)>!<IMG $1 alt="text">!sig if $1!~m/alt/!;

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I believe there is a conditional regex needed here but all attempts at success are giving me a brutal headache.
Any one deal with this kind of situation before?
Sherab

In reply to Conditional regex by sherab

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