Apart from the problem of having to specify all the possible tag names up front in an array, this approach will fail to pick up on certain problems that are quite common, such as: 
<foo><bar> blah blah </foo></bar>

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In fact, by this approach, a file where open and close tags are positioned randomly will pass just fine, so long as the number of close tags matches the number of open tags for each tag name.

In reply to Re^2: Pair Tag missing by graff
in thread Pair Tag missing by Anonymous Monk

Title:
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