Current issues with Value

[torkleyy]

• tuples / tuple structs not supported (Ron does not properly round trip through Value #121)
• enums not supported
• struct names don't get stored
• units represented with struct names
• Make sure errors make sense, esp after a unit struct (e.g. UnitStruct: as input)
• figure out what to do about tuples becoming sequences

[Boscop]

Can some of these boxes be ticket now? It seems at least the first one can..

[github-actions]

Issue has had no activity in the last 180 days and is going to be closed in 7 days if no further activity occurs

[kvark]

comment

[wiiznokes]

Any plans on improving this or this is out of scope ?

[juntyr]

Yes, many plans, little time (research + small child) :/ If you can help with any part, I'd really appreciate it :)

[wiiznokes]

Yes, many plans, little time (research + small child) :/ If you can help with any part, I'd really appreciate it :)

I'm interested in making the conversion "ron str" -> ron::Value lossless. Maybe i could try to implement it, but i think it would help if you can give some hint about the change needed in the Value type.

[juntyr]

Yes, many plans, little time (research + small child) :/ If you can help with any part, I'd really appreciate it :)

I'm interested in making the conversion "ron str" -> ron::Value lossless. Maybe i could try to implement it, but i think it would help if you can give some hint about the change needed in the Value type.

Essentially the Value type would need to become an AST-like type for everything the current grammar can represent. Then ron string -> Value -> string would be lossless.

You can find the grammar here: https://github.com/ron-rs/ron/blob/master/docs/grammar.md (it even has a Value section).

[wiiznokes]

Ok, i've got smtg like this:

pub enum Value {
    Bool(bool),
    Char(char),
    Map(Map),
    Struct(Option<String>, Map),
    Number(Number),
    Option(Option<Box<Value>>),
    String(String),
    Bytes(Vec<u8>),
    Seq(Vec<Value>),
    Tuple(Option<String>, Vec<Value>),
    Unit,
}

[juntyr]

Ok, i've got smtg like this:

pub enum Value {
    Bool(bool),
    Char(char),
    Map(Map),
    Struct(Option<String>, Map),
    Number(Number),
    Option(Option<Box<Value>>),
    String(String),
    Bytes(Vec<u8>),
    Seq(Vec<Value>),
    Tuple(Option<String>, Vec<Value>),
    Unit,
}

I’d probably make the following changes:

• rename Seq to List
• struct should use a map with string keys
• we also need a named unit variant with a string field (e.g. for unit structs and unit variants)

[wiiznokes]

we also need a named unit variant with a string field (e.g. for unit structs and unit variants)

I was thinking of using Struct(None, empty::map) for "()", and Struct(Some("name"), empty::map) for unit_struct with indent.
For enum_variant_unit, we can use Tuple(Some("name"), empty::vec).

Do you still think it's better to add a new variant ? In that case, maybe UnitStruct(Option<String>)