yes, everything is an infix operator :)

`1 + 2` sends the message `\ + 2` to `1`

`a foo ()` sends the message `\ foo () ` to `a` (the parenthesis are the nil value)

`1 + 2 - 3` sends the message `\ + 2` to `1` and then the message `- 3` to the result of the previous message send