`VarInfo` and `SimpleVarInfo`

[yebai]

It would help informed discussions and decisions to have a careful comparison of SimpleVarInfo and VarInfo, including:

• their functionalities
• their differences
• each data structure's advantages and disadvantages
• features supported by VarInfo but currently lacking in SimpleVarInfo

[penelopeysm]

The big table of AbstractVarInfo methods

I was prompted to post this here.

AbstractVarInfo requires the following functions to be implemented.
Functions marked with * have default implementations and are thus optional.

* default_transformation(::Model, ::AbstractVarInfo)
transformation(::AbstractVarInfo)
getlogp(::AbstractVarInfo)
setlogp!!(::AbstractVarInfo, logp::Any)
* acclogp!!(::AbstractContext, ::AbstractVarInfo, logp::Any)
acclogp!!(::AbstractVarInfo, logp::Any)
resetlogp!!(::AbstractVarInfo)
Base.keys(::AbstractVarInfo)
Base.getindex(::AbstractVarInfo, ::VarName)
Base.getindex(::AbstractVarInfo, ::VarName, ::Distribution
Base.getindex(::AbstractVarInfo, ::Vector{VarName})
Base.getindex(::AbstractVarInfo, ::Vector{VarName}, ::Distribution)
Base.getindex(::AbstractVarInfo, ::Colon)
getindex_internal(::AbstractVarInfo, ::VarName)
getindex_internal(::AbstractVarInfo, ::Vector{VarName})
getindex_internal(::AbstractVarInfo, ::Colon)
BangBang.empty!!(::AbstractVarInfo)
Base.isempty(::AbstractVarInfo)
values_as(::AbstractVarInfo, ::Type)
* Base.eltype(::AbstractVarInfo)
* has_varnamedvector(::AbstractVarInfo)
subset(::AbstractVarInfo, ::AbstractVector{<:VarName})
Base.merge(::AbstractVarInfo, ::AbstractVarInfo)
istrans(::AbstractVarInfo)
istrans(::AbstractVarInfo, ::AbstractVector)
settrans!!(::AbstractVarInfo, ::Bool)
settrans!!(::AbstractVarInfo, ::Bool, ::VarName)
* link!!(::AbstractVarInfo, ::Model)
link!!(::AbstractTransformation, AbstractVarInfo, ::Model)
* link!!(::AbstractVarInfo, ::NTuple{N,VarName}, ::Model) where N
link!!(::AbstractTransformation, ::AbstractVarInfo, ::NTuple{N,VarName}, ::Model) where N
* invlink!!(::AbstractVarInfo, ::Model)
invlink!!(::AbstractTransformation, AbstractVarInfo, ::Model)
* invlink!!(::AbstractVarInfo, ::NTuple{N,VarName}, ::Model) where N
invlink!!(::AbstractTransformation, ::AbstractVarInfo, ::NTuple{N,VarName}, ::Model) where N
* maybe_invlink_before_eval!!(::AbstractVarInfo, ::Model)
maybe_invlink_before_eval!!(::AbstractTransformation, ::AbstractVarInfo, ::Model)
unflatten(::AbstractVarInfo, ::AbstractVector)
* to_maybe_linked_internal(::AbstractVarInfo, ::VarName, dist::Any, val::Any)
* from_maybe_linked_internal(::AbstractVarInfo, ::VarName, dist::Any, val::Any)
* invlink_with_logpdf(::AbstractVarInfo, ::VarName, dist::Any)
* invlink_with_logpdf(::AbstractVarInfo, ::VarName, dist::Any, val::Any)
* increment_num_produce!(::AbstractVarInfo)
from_internal_transform(::AbstractVarInfo, ::VarName)
from_internal_transform(::AbstractVarInfo, ::VarName, ::Distribution)
from_linked_internal_transform(::AbstractVarInfo, ::VarName)
from_linked_internal_transform(::AbstractVarInfo, ::VarName, ::Distribution)
* from_maybe_linked_internal_transform(::AbstractVarInfo, ::VarName)
* from_maybe_linked_internal_transform(::AbstractVarInfo, ::VarName, ::Distribution)
* to_internal_transform(::AbstractVarInfo, ::VarName)
* to_internal_transform(::AbstractVarInfo, ::VarName, ::Distribution)
* to_linked_internal_transform(::AbstractVarInfo, ::VarName)
* to_linked_internal_transform(::AbstractVarInfo, ::VarName, ::Distribution)
* to_maybe_linked_internal_transform(::AbstractVarInfo, ::VarName)
* to_maybe_linked_internal_transform(::AbstractVarInfo, ::VarName, ::Distribution)
* internal_to_linked_internal_transform(::AbstractVarInfo, ::VarName)
* internal_to_linked_internal_transform(::AbstractVarInfo, ::VarName, ::Distribution)
* linked_internal_to_internal_transform(::AbstractVarInfo, ::VarName)
* linked_internal_to_internal_transform(::AbstractVarInfo, ::VarName, ::Distribution)

[mhauru]

Closed by #1183