jldsave function API

[JonasIsensee]

This PR adds a new API function that leverages julia's keyword argument syntax.

julia> using JLD2
[ Info: Precompiling JLD2 [033835bb-8acc-5ee8-8aae-3f567f8a3819]

julia> hello = 1
1

julia> jldsave("test.jld2"; hello, world = 2)

julia> using FileIO

julia> load("test.jld2")
Dict{String, Any} with 2 entries:
  "hello" => 1
  "world" => 2

[codecov]

Codecov Report

Merging #297 (582356e) into master (8cb9a08) will increase coverage by 0.02%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master     #297      +/-   ##
==========================================
+ Coverage   90.30%   90.32%   +0.02%     
==========================================
  Files          26       26              
  Lines        2641     2647       +6     
==========================================
+ Hits         2385     2391       +6     
  Misses        256      256              

Impacted Files	Coverage Δ
src/JLD2.jl	91.86% <ø> (ø)
src/loadsave.jl	95.23% <100.00%> (+0.36%)	⬆️

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[lhupe]

hmm, I like this syntax a lot, but I'm starting to think that it might be more useful to add it to the FileIO API (as an alternative zero-argument method). After all, it does basically the same thing (store key-value pairs in a JLD2 file) and I personally think the current FileIO.save("filename.jld2", "key1", value1, "key2", value2) syntax is a bit weird.

[johnnychen94]

A compatible workaround to JuliaIO/FileIO.jl#324:

fileio_save(f::File{format"JLD2"}, ::Nothing; kwargs...) = jldsave(FileIO.filename(f); kwargs...)

and use save("test.jld2", nothing; x, y, zebra=z). A little bit weird for nothing though but it works. How do you think of this?

[JonasIsensee]

A compatible workaround to JuliaIO/FileIO.jl#324:

fileio_save(f::File{format"JLD2"}, ::Nothing; kwargs...) = jldsave(FileIO.filename(f); kwargs...)

and use save("test.jld2", nothing; x, y, zebra=z). A little bit weird for nothing though but it works. How do you think of this?

Thank you for the suggestion but I'm not convinced.
I don't think that is a valid option. I'd rather use a new function name than having to pass an arbitrary nothing just to make dispatch work.

[johnnychen94]

JuliaIO/FileIO.jl#324 is a breaking change so even if it's approved, it needs time to adopt. Before that actually get supported, save("test.jld2", nothing; x, y, zebra=z) is a forward-compatible workaround.