extend Float
    method asFloat
        self

    method printOn: stream
        stream writeUTF8: self toString

    method displayOn: stream
        self printOn: stream

    method to: other
       self to: other by: 1.0

    method to: other by: step
       Interval from: self to: other by: step

    method + x
        x addFloat: self
    method - x
        x subFloat: self
    method * x
        x mulFloat: self
    method / x
        x divFloat: self

    method square
        self mulFloat: self

    method == x
        x equalFloat: self
    method < x
        x greaterThanFloat: self
    method > x
        x lessThanFloat: self
    method <= x
        x greaterThanOrEqualFloat: self
    method >= x
        x lessThanOrEqualFloat: self

    method addInteger: x
        self addFloat: x asFloat
    method subInteger: x
        self subFloat: x asFloat
    method mulInteger: x
        self mulFloat: x asFloat
    method divInteger: x
        self divFloat: x asFloat

    method addArray: x
        x collect: { |elt| elt addFloat: self }
    method mulArray: x
        x collect: { |elt| elt mulFloat: self }
    method subArray: x
        -- FIXME: Should the arith protocol include reverses mul and sub?
        x collect: { |elt| elt - self }
    method divArray: x
        x collect: { |elt| elt / self }

    method equalInteger: x
        self equalFloat: x asFloat
    method lessThanInteger: x
        self lessThanFloat: x asFloat
    method greaterThanInteger: x
        self greaterThanFloat: x asFloat
    method lessThanOrEqualInteger: x
        self lessThanOrEqualFloat: x asFloat
    method greaterThanOrEqualInteger: x
        self greaterThanOrEqualFloat: x asFloat

    method atLeast: min atMost: max
        let min = min asFloat.
        (self lessThanFloat: min)
            ifTrue: { return min }.
        let max = max asFloat.
        (self greaterThanFloat: max)
            ifTrue: { return max }.
        self
end