WIT.md top level document definition

[patrickhuber]

I'm looking at the definition for top level document here:

https://github.com/WebAssembly/component-model/blob/main/design/mvp/WIT.md#top-level-items

It is defined as:

wit-document ::= interface-item*

Which is a sequence of 0..N interface-item instances, defined as:

interface-item ::= 'interface' id strlit? '{' interface-items* '}'

Would this imply that a wit document can only consist of 0..N interfaces? This doesn't seem correct, as I can see examples here: https://github.com/WebAssembly/wasi-sockets/blob/main/common-types.wit where record, enum and type are top level elements.

Is this a typo? Should the definition instead be:

wit-document ::= interface-items*

That would allow for 0..N interface-item, which are defined as:

interface-items ::= resource-item
                  | variant-items
                  | record-item
                  | union-items
                  | flags-items
                  | enum-items
                  | type-item
                  | use-item
                  | func-item

[patrickhuber]

I looked up the wit parser here https://docs.rs/wit-parser/latest/wit_parser/struct.Document.html and it appears the spec files for the wasi-sockets proposal are actually incorrect.

Top level elements can be one of 'world' or 'interface'