Map string <-> ettBinary, []byte -> ettBitBinary

[heri16]

Implement encode/decode for the types below without affecting node logic. (All tests pass)

Mapping Types

Golang Type	ETF Type
string	binary
[]byte	bitBinary

Pros:

• [x] Support longer strings (now max length is 4294967295, previously was 65535)

Cons:

• [x] []byte are now sent as ETF bit_binary with bits set to 8. (Overhead of 1 byte)

[CLAassistant]

All committers have signed the CLA.

[halturin]

explanation https://github.com/halturin/ergo/pull/68#discussion_r680967840 why this approach can't be accepted

[heri16]

First off, thanks so much for the great work on this library.

I hope to be able to bring to light the extensive research done by the Elixir team with regards to interoperability with Erlang: https://elixirschool.com/en/lessons/advanced/erlang/#strings

Please see https://github.com/halturin/ergo/pull/68#discussion_r681109604 on why this approach should be accepted.

[heri16]

I'll let the creator of Erlang explain further:

https://elixirforum.com/t/why-are-charlist-and-string-co-existing-in-erlang/31566

[heri16]

Two different erlang authors interfacing to lua<-> erlang.

Both came to the same conclusion independently, that erlang's binary-strings should be mapped to lua "string", and erlang's list-strings should be mapped to lua lists.

https://github.com/rtraschke/erlang-lua#value-translation-from-erlang-to-lua

https://github.com/rvirding/luerl/wiki/0.7-Data-representation#data-types

https://github.com/rvirding/luerl/wiki/0.7-Data-representation#strings

[halturin]

Because Lua doesn't have a binary type. Anyway, you may want to try my implementation in the 'otp2324' branch. See README file there.

[heri16]

Ruby has byte arrays.

See how types are mapped: http://www.erlang-factory.com/upload/presentations/36/tom_preston_werner_erlectricity.pdf

[halturin]

Who said that's a good mapping? :) especially looking at

... let alone this project is on hold last 13 years ))

Feel free to make a fork with data mapping you like. This PR won't be accepted. I've made etf.String and etf.Charlist to support interaction with Erlang/Elixir and it should be enough so far

[halturin]

not valid any more