my $xmlish = <<'END';
<whatever><book-part type='closed'>
Chapter 1
</book-part>
<book-part type='unclosed'>
Chapter 2
<book-part type='final'>
Chapter 3
</whatever>
END

my $prev = '/';
$xmlish =~ s{(?=<\s*(/?)\s*book-part\b)}{
    (   ! $prev  &&  ! $1  ?  '</book-part>'  :  '',
        $prev= $1,
    )[0]
}ge;

print $xmlish;
__END__
<whatever><book-part type='closed'>
Chapter 1
</book-part>
<book-part type='unclosed'>
Chapter 2
</book-part><book-part type='final'>
Chapter 3
</whatever>

[download]

Assumes no <book-part bits inside attribute values, comments, nor CDATA blocks, of course. Not using an XML parser since missing closing tags means you don't really have XML that a real XML parser would handle. Also note how it doesn't insert a final closing tag (you didn't provide enough information for me to know how to do that for your case).

- tye        

In reply to Re: XML tag closing (naive way) by tye
in thread XML tag closing by maha

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