Function int [src]

Returns a random int i such that minInt(T) <= i <= maxInt(T). i is evenly distributed.

Prototype

pub fn int(r: Random, comptime T: type) T

Parameters

r: RandomT: type

Source

  pub fn int(r: Random, comptime T: type) T {
    const bits = @typeInfo(T).int.bits;
    const UnsignedT = std.meta.Int(.unsigned, bits);
    const ceil_bytes = comptime std.math.divCeil(u16, bits, 8) catch unreachable;
    const ByteAlignedT = std.meta.Int(.unsigned, ceil_bytes * 8);

    var rand_bytes: [ceil_bytes]u8 = undefined;
    r.bytes(&rand_bytes);

    // use LE instead of native endian for better portability maybe?
    // TODO: endian portability is pointless if the underlying prng isn't endian portable.
    // TODO: document the endian portability of this library.
    const byte_aligned_result = mem.readInt(ByteAlignedT, &rand_bytes, .little);
    const unsigned_result: UnsignedT = @truncate(byte_aligned_result);
    return @bitCast(unsigned_result);
}  