It's not ambiguous.

Something like: 

print (1,2)[0];

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is ambiguous---it could be 
(print(1,2))[0];

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or 
print((1,2))[0];

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Perl's not sure which you mean, so it issues a warning (if you have warnings enabled), and arbitrarily chooses the second.

Now this is a little bit silly, since the second interpretation is a syntax error, and you can argue that Perl should be smarter about this, but it's not, so you have to be more explicit.

Running with warnings on will help you catch errors like this more easily; if you don't understand them, sending them to splain will help: 

$ perl -we'print (1,2)[0];' 2>&1 |splain
print (...) interpreted as function at -e line 1 (#1)
    (W syntax) You've run afoul of the rule that says that any list op
+erator
    followed by parentheses turns into a function, with all the list
    operators arguments found inside the parentheses.  See 
    perlop/Terms and List Operators (Leftward).
...

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In reply to Re: Re: Re: Confused about unary + by sgifford
in thread Confused about unary + by Not_a_Number

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