gistfile1.rb

    require 'quantity/all'
    1.meter                                                 #=> 1 meter
    1.meter.to_feet                                         #=> 3.28083... foot
    c = 299792458.meters / 1.second                         #=> 299792458 meter/second
    
    newton = 1.meter * 1.kilogram / 1.second**2             #=> 1 meter*kilogram/second^2
    newton.to_feet                                          #=> 3.28083989501312 foot*kilogram/second^2
    newton.convert(:feet)                                   #=> 3.28083989501312 foot*kilogram/second^2
    jerk_newton / 1.second                                  #=> 1 meter*kilogram/second^3
    jerk_newton * 1.second == newton                        #=> true

    mmcubed = 1.mm.cubed                                    #=> 1 millimeter^3
    mmcubed * 1000 == 1.milliliter                          #=> true

    [1.meter, 1.foot, 1.inch].sort                          #=> [1 inch, 1 foot, 1 meter]

    m_to_f = Quantity::Unit.for(:meter).convert_proc(:feet)
    m_to_f.call(1)                                          #=> 3.28083... (or a Rational)