Please use <code> tags for your string patterns, it is currently very difficult to figure out exactly what you need.

A shoot in the dark which, even if it may not be exactly what you need, might still provide you some help:: 

my $regex = qr/\w{3}_[tr]x_[pn]\d/;

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In reply to Re: regular expression to match specific members of a bus_name by Laurent_R
in thread regular expression to match specific members of a bus_name by boleary

Title:
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