basics/complexes/protocol_parens.rb

tests/_examples/basics/complexes/protocol_parens.rb in the metorex repository.

# `Complex::I` is the imaginary unit every other Complex is measured against.
p(Complex::I)
p(Complex::I * Complex::I)

# The numerator scales both parts to the denominator they share.
p(Complex(Rational(7, 8), Rational(8, 4)).numerator)
p(Complex(Rational(3, 8), Rational(3, 4)).denominator)

# Two Complexes with nothing on the imaginary axis order by their real parts,
# and anything else has no order at all.
p(Complex(5) <=> Complex(2))
p(Complex(5) <=> 2)
p(Complex(5, 1) <=> Complex(2))

# `eql?` compares the parts by class as well as by value.
p(Complex(1, 2).eql?(Complex(1, 2)))
p(Complex(1, 2).eql?(Complex(1, 2.0)))

# A Complex names no point on the number line, so it answers neither question
# a real number does.
p(Complex(1, 2).respond_to?(:positive?))

# A number is not built by hand, and a clone cannot ask for an unfrozen one.
begin
  Float.new(1.0)
rescue NoMethodError => error
  puts(error.message)
end

begin
  1.clone(freeze: false)
rescue ArgumentError => error
  puts(error.message)
end

# Numeric answers the parts of the fraction it stands for.
p(3.numerator)
p(0.5.denominator)

Output:

(0+1i)
(-1+0i)
(7+16i)
8
1
1
nil
true
false
false
undefined method 'new' for class 'Float'
can't unfreeze Integer
3
2