Your match loop matches a particular pattern in the file ignoring all other sections. The matched section that you want to remove is identified by a condition (location and obj_name) The problem is that you always add the just matched section to $list. The line adding on to $list should be in your conditional statement. 
unless (($a eq $location) and ($b eq $obj_name)) { 
  $list=$list. "<?--$a-$b-->$c</?--$d-$e-->\n";
}

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This should add to the list except when the condition is true. I would have like to test this code but you did not give any sample data.

P.S. I noted that your question has a low reputation. I suspect that the lack of sample data may have contributed to it.

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In reply to Re: Deleting on Text File by admiraln
in thread Deleting on Text File by Anonymous Monk

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