Regarding your Seed() function

[lordmulder]

Hello,

regarding your seeding function:

func (w *weyl) Seed(seed int64) {
    *w = weyl{s: (uint64(seed) + 0xb5ad4eceda1ce2a9) | 1}
}

Considering that seed values will often not use the full 64-Bit – which probably means that more often than not the "highest" bits will be zero-padding and the entropy is in the "lowest" bits:

Wouldn't it make sense to left-shift the seed value by one bit-position, rather than OR-ing it with 1?

func (w *weyl) Seed(seed int64) {
    *w = weyl{s: (uint64(seed) << 1) + 0xb5ad4eceda1ce2a9}
}

Note: Still guarantees that the result is odd (as the shifted value is always even and it will be added to an odd number), but rather than discarding the least-significant bit, we discard the most-significant one.

Regards,
MuldeR

[tidwall]

Hi @lordmulder,

Yes, I like this approach very much.