domain([0, 1]).range([0, 1]):
         -0.5  ->   0.250
          0.0  ->   0.000
          0.5  ->   0.250
          1.0  ->   1.000
          1.5  ->   2.250

domain([1, 2]).range([0, 1]):
          0.5  ->  −0.250
          1.0  ->   0.000
          1.5  ->   0.417
          2.0  ->   1.000
          2.5  ->   1.750

domain([01/01/1990, 01/01/1991]).range([0, 1]):
   10/20/1989  ->  −0.194
   01/01/1990  ->   0.000
   03/15/1990  ->   0.196
   05/27/1990  ->   0.394
   01/01/1991  ->   1.000
   03/15/1991  ->   1.206

domain([0, 1]).range(["red", "blue"]):
         -0.5  ->  rgb(191,0,64)
          0.0  ->  rgb(255,0,0)
          0.5  ->  rgb(191,0,64)
          1.0  ->  rgb(0,0,255)
          1.5  ->  rgb(-319,0,574)

domain([0, 1]).range(["red", "blue"]).interpolate(hsl):
        -0.50  ->  #ffff00
         0.00  ->  #ff0000
         0.50  ->  #ffff00
        √0.50  ->  #00ff00
         1.00  ->  #0000ff
         2.00  ->  #0000ff

domain clamping:
        under  ->  0
         over  ->  1