Expand String Conversion Support To Full Utf-16 Range of Code Points about purescript-arraybuffer

[AlexaDeWit]

Doing some investigating related to this...

It looks like fromCodePoint and codePointAt use the binary code point representation, which omits the "1101 1" leader bits.'

https://en.wikipedia.org/wiki/UTF-16#Examples

This means that to encode a complete string in a Uint16Array buffer, we're going to need to do the translation between that smaller binary space to the full 32 bits and then split them by byte pairs.

That is to say, we need to translate from this encoding:
"0001 0000 0100 0011 0111" 20 bits, to this encoding: "D801 DC37", 32 bits.

This is not a simple as a simple split and append however, as the first 10 bits may change during the translation. See the UTF-16 for better specifics.

[AlexaDeWit]

A little note to this, that way quickcheck reasons about strings, they are only generated in the first 65k form, so we don't have a truly comprehensive dataset without generating it for this.

[AlexaDeWit]

The polyfills can provide essentially most of the behaviour needed if extracting the relevant components.

To do this without risk of stack overflows and efficiently is likely going to involve mutation. If I get to writing it this weekend it will likely be implemented in JS I'm afraid, rather than via folds in purescript.

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/fromCodePoint

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/codePointAt

[AlexaDeWit]

I think it might actually be possible to use the lazy approach and make use of purescript-encoding with the polyfill. I will do an experiment once my PR to the encoding lib goes through to update it to 0.12.

The user seems inactive so I may start maintaining a fork if necessary, given that no contact details exist for them.

[AlexaDeWit]

I think we can effectively close this, as #17 is probably the upper limit of what we're going to get unless we do a total re-implementation.