So, two + 2 is interpreted as two(2).

And that's because the following are all the same: 

two + 2
two +2
two(+2)
two(2)

[download]

Omitting parens around arguments can lead to weird problems. You've encountered one. You can disambiguate as follows: 

two() + 2
(two) + 2

[download]

You could also add a prototype to two.

In reply to Re: two + 2 not equal 4! by ikegami
in thread two + 2 not equal 4! by kp2a

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