I’m writing an ELO calculator.

const PD_TABLE: [(u16, u16, f32)] = [
  (0, 3, 0.50),
  (4, 10, 0.51),
  (11, 17, 0.52),
  (18, 25, 0.53),
  (26, 32, 0.54),
  (33, 39, 0.55),
  (40, 46, 0.56),
  (47, 53, 0.57),
  (54, 61, 0.58),
  (62, 68, 0.59),
  (69, 76, 0.60),
  (77, 83, 0.61),
  (84, 91, 0.62),
  (92, 98, 0.63),
  (99, 106, 0.64),
  (107, 113, 0.65),
  (114, 121, 0.66),
  (122, 129, 0.67),
  (130, 137, 0.68),
  (138, 145, 0.69),
  (146, 153, 0.70),
  (154, 162, 0.71),
  (163, 170, 0.72),
  (171, 179, 0.73),
  (180, 188, 0.74),
  (189, 197, 0.75),
  (198, 206, 0.76),
  (207, 215, 0.77),
  (216, 225, 0.78),
  (226, 235, 0.79),
  (236, 245, 0.80),
  (246, 256, 0.81),
  (257, 267, 0.82),
  (268, 278, 0.83),
  (279, 290, 0.84),
  (291, 302, 0.85),
  (303, 315, 0.86),
  (316, 328, 0.87),
  (329, 344, 0.88),
  (345, 357, 0.89),
  (358, 374, 0.90),
  (375, 391, 0.91),
  (392, 411, 0.92),
  (412, 432, 0.93),
  (433, 456, 0.94),
  (457, 484, 0.95),
  (485, 517, 0.96),
  (518, 559, 0.97),
  (560, 619, 0.98),
  (620, 735, 0.99),
  (735, 10000, 1.00),
];

I’m getting the following error :

the size for values of type [(u16, u16, f32)] cannot be known at compilation time
the trait Sized is not implemented for [(u16, u16, f32)]

However it seems pretty clear to me what the size of such a record would be. I don’t why the compiler can’t compute it. How can I help it out ?