Print out your data to see if it is really what you think it is. Part of the data structure hasn't been populated.

use Data::Dumper;

...

print Dumper $tree->{children}[0];    

# if the above produced more than "$VAR1 = {};" or "$VAR1 = undef;", p
+ost
# those results back here. If it didn't, perform the following
# and post those results

print Dumper $tree;

...

@{$tree->{children}}[0]->{label} =~ s/^\*//;

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In reply to Re: Can't use an undefined value as a HASH reference by stevieb
in thread Can't use an undefined value as a HASH reference by Anonymous Monk

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