domain([0, 1]).range([0, 1]):
         -0.5  ->  −0.500
          0.0  ->   0.000
          0.5  ->   0.500
          1.0  ->   1.000
          1.5  ->   1.500

domain([1, 2]).range([0, 1]):
          0.5  ->  −0.500
          1.0  ->   0.000
          1.5  ->   0.500
          2.0  ->   1.000
          2.5  ->   1.500

domain([01/01/1990, 01/01/1991]).range([0, 1]):
   10/20/1989  ->  −0.200
   01/01/1990  ->   0.000
   03/15/1990  ->   0.200
   05/27/1990  ->   0.400
   01/01/1991  ->   1.000
   03/15/1991  ->   1.200

domain([0, 1]).range(["red", "blue"]):
         -0.5  ->  rgb(383,0,-127)
          0.0  ->  rgb(255,0,0)
          0.5  ->  rgb(128,0,128)
          1.0  ->  rgb(0,0,255)
          1.5  ->  rgb(-127,0,383)

domain([0, 1]).range(["red", "blue"]).interpolate(hsl):
         -0.5  ->  #0000ff
          0.0  ->  #ff0000
          0.5  ->  #00ff00
          1.0  ->  #0000ff
          1.5  ->  #ff0000

domain coercion:
       String  ->  [ 1, 2 ]
         Date  ->  [ 631180800000, 662716800000 ]
       Number  ->  [ 41, 42 ]

domain coercion, invert:
       String  ->  1
         Date  ->  646948800000
       Number  ->  21

range coercion, invert:
       String  ->  0.5
         Date  ->  0.5
       Number  ->  0.5
          ???  ->  NaN

ticks:
            1  ->  0, 1
            2  ->  0.0, 0.5, 1.0
            5  ->  0.0, 0.2, 0.4, 0.6, 0.8, 1.0
           10  ->  0.0, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0

descending ticks:
            1  ->  0, 1
            2  ->  0.0, 0.5, 1.0
            5  ->  0.0, 0.2, 0.4, 0.6, 0.8, 1.0
           10  ->  0.0, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0

domain clamping:
   inspection  ->  true
        under  ->  0
         over  ->  1

domain clamping reversed:
        under  ->  1
         over  ->  0

domain unclamping:
        under  ->  -1
         over  ->  11

nice():
   [ 1.100, 10.900 ]    ->   1.000, 11.000
   [ 10.900, 1.100 ]    ->   11.000, 1.000
   [ 0.700, 11.001 ]    ->   0.000, 12.000
   [ 123.100, 6.700 ]   ->   130.000, 0.000
   [ 0.000, 0.490 ]     ->   0.000, 0.500