smalltalk.sample

exampleWithNumber: x
    | y |
    true & false not & (nil isNil) ifFalse: [self halt].
    y := self size + super size.
    #($a #a 'a' 1 1.0)
        do: [ :each |
            Transcript show: (each class name);
                       show: ' '].
    ^x < y

"From https://en.wikipedia.org/wiki/Smalltalk"