Document what works and what doesn't

[minecraft2048]

Some data types surprisingly works, and some data types unsurprisingly doesn't work

using StructIO
using EnumX
using StaticArrays

# Some data types that surprisingly works

@enumx RetCode::Int8 begin
    NO_ERROR
    INVALID_ERROR
    HELLO_WORLD
    STREIBOUGH
end

@io struct Reply
    rc::RetCode.T
    result::Int
end align_packed #StructIO works with EnumX enums

@io struct Nested
    msgid::UInt8
    msg::Reply
end align_packed #StructIO can successfully deserialize nested structs

@io struct Fixed
    num::Int
    vec::SVector{16,UInt8}
end align_packed #StructIO works with StaticArrays

#Some data types that doesn't work

@io struct Cursed
    st::String
    num::Int
end align_packed # Unsurprisingly doesn't work as string is a variable length array

@io struct Trailing
    num::Int
    vec::Vector{UInt8}
end align_packed 

[stevengj]

As I understand it, it only works with bitstypes. isbitstype(Cursed) returns false.