The first line has syntax error, print need's a comma or a period between } and "\n". I think you meant this: 
my $columns = [ qw (one two three) ]; # sample data is GOOD
print join "\t",@{$columns}. "\n";
print join ("\t",@{$columns}). "\n";

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I dropped OUT , because it doesn't matter if we are using STDOUT or another handle. So, the first line prints out "3" while the second line prints out the elements of $columns joined by tabs.

What happened to the first line? Precendance my friend, the dot causes @{$columns} to be evaluated in scalar context, leaving join only one element to well, join: "3\n".

That's why i like to use a comma instead: 

print join "\t",@{$columns}, "\n";

[download]

jeffa 

L-LL-L--L-LL-L--L-LL-L--
-R--R-RR-R--R-RR-R--R-RR
F--F--F--F--F--F--F--F--
(the triplet paradiddle)

In reply to (jeffa) Re: Not really obfuscation, but..... by jeffa
in thread Scalar vs. array context w/ join() by mdupont

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