from

pub fn from(comptime T: type) Self

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pub fn from(comptime T: type) Self {
    return switch (T) {
        f16 => .{
            // Fast-Path
            .min_exponent_fast_path = -4,
            .max_exponent_fast_path = 4,
            .max_exponent_fast_path_disguised = 7,
            .max_mantissa_fast_path = 2 << std.math.floatMantissaBits(T),
            // Slow + Eisel-Lemire
            .mantissa_explicit_bits = std.math.floatFractionalBits(T),
            .infinite_power = 0x1f,
            // Eisel-Lemire
            .smallest_power_of_ten = -26, // TODO: refine, fails one test
            .largest_power_of_ten = 4,
            .minimum_exponent = -15,
            // w >= (2m+1) * 5^-q and w < 2^64
            // => 2m+1 > 2^11
            // => 2^11*5^-q < 2^64
            // => 5^-q < 2^53
            // => q >= -23
            .min_exponent_round_to_even = -22,
            .max_exponent_round_to_even = 5,
        },
        f32 => .{
            // Fast-Path
            .min_exponent_fast_path = -10,
            .max_exponent_fast_path = 10,
            .max_exponent_fast_path_disguised = 17,
            .max_mantissa_fast_path = 2 << std.math.floatMantissaBits(T),
            // Slow + Eisel-Lemire
            .mantissa_explicit_bits = std.math.floatFractionalBits(T),
            .infinite_power = 0xff,
            // Eisel-Lemire
            .smallest_power_of_ten = -65,
            .largest_power_of_ten = 38,
            .minimum_exponent = -127,
            .min_exponent_round_to_even = -17,
            .max_exponent_round_to_even = 10,
        },
        f64 => .{
            // Fast-Path
            .min_exponent_fast_path = -22,
            .max_exponent_fast_path = 22,
            .max_exponent_fast_path_disguised = 37,
            .max_mantissa_fast_path = 2 << std.math.floatMantissaBits(T),
            // Slow + Eisel-Lemire
            .mantissa_explicit_bits = std.math.floatMantissaBits(T),
            .infinite_power = 0x7ff,
            // Eisel-Lemire
            .smallest_power_of_ten = -342,
            .largest_power_of_ten = 308,
            .minimum_exponent = -1023,
            .min_exponent_round_to_even = -4,
            .max_exponent_round_to_even = 23,
        },
        f80 => .{
            // Fast-Path
            .min_exponent_fast_path = -27,
            .max_exponent_fast_path = 27,
            .max_exponent_fast_path_disguised = 46,
            .max_mantissa_fast_path = 2 << std.math.floatMantissaBits(T),
            // Slow + Eisel-Lemire
            .mantissa_explicit_bits = std.math.floatFractionalBits(T),
            .infinite_power = 0x7fff,
            // Eisel-Lemire.
            // NOTE: Not yet tested (no f80 eisel-lemire implementation)
            .smallest_power_of_ten = -4966,
            .largest_power_of_ten = 4932,
            .minimum_exponent = -16382,
            // 2^65 * 5^-q < 2^80
            // 5^-q < 2^15
            // => q >= -6
            .min_exponent_round_to_even = -6,
            .max_exponent_round_to_even = 28,
        },
        f128 => .{
            // Fast-Path
            .min_exponent_fast_path = -48,
            .max_exponent_fast_path = 48,
            .max_exponent_fast_path_disguised = 82,
            .max_mantissa_fast_path = 2 << std.math.floatMantissaBits(T),
            // Slow + Eisel-Lemire
            .mantissa_explicit_bits = std.math.floatFractionalBits(T),
            .infinite_power = 0x7fff,
            // Eisel-Lemire.
            // NOTE: Not yet tested (no f128 eisel-lemire implementation)
            .smallest_power_of_ten = -4966,
            .largest_power_of_ten = 4932,
            .minimum_exponent = -16382,
            // 2^113 * 5^-q < 2^128
            // 5^-q < 2^15
            // => q >= -6
            .min_exponent_round_to_even = -6,
            .max_exponent_round_to_even = 49,
        },
        else => unreachable,
    };
}