Thanks thor,
That was a good suggestion. Unfortunately it didn't work. When my script executes ...

#
# link the holes
#
$holes[0]->setLinks(  [ $holes[1], $holes[2] ] );
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... it generates this error message ...

Can't locate object method "setLinks" via package "hole=HASH(0x1a1c2e4
+)
" (perhaps you forgot to load "hole=HASH(0x1a1c2e4)
"?) at ./tieBoardTree.pl line 26, <$fh> line 3.
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