zig/lib/std / math/big.zig 

const std = @import("../std.zig");
const assert = std.debug.assert;

Rational

big/rational.zig 

pub const Rational = @import("big/rational.zig").Rational;

int

big/int.zig 
pub const int = @import("big/int.zig");

Limb

 
pub const Limb = usize;
const limb_info = @typeInfo(Limb).int;

SignedLimb

 
pub const SignedLimb = std.meta.Int(.signed, limb_info.bits);

DoubleLimb

 
pub const DoubleLimb = std.meta.Int(.unsigned, 2 * limb_info.bits);

HalfLimb

 
pub const HalfLimb = std.meta.Int(.unsigned, limb_info.bits / 2);

SignedDoubleLimb

 
pub const SignedDoubleLimb = std.meta.Int(.signed, 2 * limb_info.bits);

Log2Limb

 
pub const Log2Limb = std.math.Log2Int(Limb);

comptime {
    assert(std.math.floorPowerOfTwo(usize, limb_info.bits) == limb_info.bits);
    assert(limb_info.signedness == .unsigned);
}

test {
    _ = int;
    _ = Rational;
    _ = Limb;
    _ = SignedLimb;
    _ = DoubleLimb;
    _ = SignedDoubleLimb;
    _ = Log2Limb;
}