Timo's Motoko wishlist

[crusso]

• shift operators for Nat (and any other operators that are available for NatX/IntX but missing for Nat/Int) — See #3112
• full matrix of conversions between fixed size NatX/IntX or at least between adjacent pairs of types (e.g. Nat8 <-> Nat16 etc).
• NatX -> Blob operations, for easy access to bytes in little-endian and perhaps big-endian encoding.
• Indexing for Blob value (blob[n] or Blob.sub(blob, n))
• (Mutable blob type for writing efficient serializers, see perhaps #3149)

@timohanke

[nomeata]

Now that we have inlining of prim wrappers (or I guess once we have that, not sure what the status is), maybe we can promise that two conversions via Nat/Int will always cancel out, instead of providing a full matrix? But may explicit is actually better.