Chains

View a chain of Daf data as a single data set. This allows creating a small Daf data set that contains extra (or overriding) data on top of a larger read-only data set. In particular this allows creating several such incompatible extra data sets (e.g., different groupings of cells to metacells), without having to duplicate the common (read only) data.

chain_reader(dafs::AbstractVector{<:DafReader}; name::Maybe{AbstractString} = nothing)::DafReader

Create a read-only chain wrapper of DafReader s, presenting them as a single DafReader . When accessing the content, the exposed value is that provided by the last data set that contains the data, that is, later data sets can override earlier data sets. However, if an axis exists in more than one data set in the chain, then its entries must be identical. This isn't typically created manually; instead call chain_reader .

chain_writer(dafs::AbstractVector{<:DafReader}; name::Maybe{AbstractString} = nothing)::DafWriter

Create a chain wrapper for a chain of DafReader data, presenting them as a single DafWriter . This acts similarly to chain_reader , but requires the final entry in the chain to be a DafWriter . Any modifications or additions to the chain are directed only at this final writer.

struct ReadOnlyChain <: DafReadOnly ... end

A wrapper for a chain of DafReader data, presenting them as a single DafReadOnly . When accessing the content, the exposed value is that provided by the last data set that contains the data, that is, later data sets can override earlier data sets. However, if an axis exists in more than one data set in the chain, then its entries must be identical. This isn't typically created manually; instead call chain_reader .

struct WriteChain <: DafWriter ... end

A wrapper for a chain of DafReader data, with a final DafWriter , presenting them as a single DafWriter . When accessing the content, the exposed value is that provided by the last data set that contains the data, that is, later data sets can override earlier data sets (where the writer has the final word). However, if an axis exists in more than one data set in the chain, then its entries must be identical. This isn't typically created manually; instead call chain_reader .

Any modifications or additions to the chain are directed at the final writer. Deletions are only allowed for data that exists only in this writer. That is, it is impossible to delete from a chain something that exists in any of the readers; it is only possible to override it.