[grammarians] ambiguity with method call?

[Terence Parr]

Howdy,

What does

foo [1]

parse as?  foo could be a variable and then foo is a simple array var:

foo = [a,b]
foo[1]

If foo is a method, it could return an array and then you could  
access the 1st element:

def foo
   return [a,b]
end
foo[1]

It could also be a method with args:

def foo x
...
end
foo [1] # same as foo([1])

This 5x ways to do anything syntax is truly a burden for the  
implementor (and as a user one of the reasons I hated perl).   
Regardless, is this a true *syntactic* ambiguity as I suspect? I.e.,  
you need to simply pick an interpretation by dictum in the manual?

Thanks,
Ter