@load should provide better error message when symbol is passed without variable names

[ngphuoc]

julia>   using JLD2,FileIO

julia>   data = 1
1

julia>   fn = "data.jld2"
"data.jld2"

julia>   JLD2.@save fn data

julia>   JLD2.@load fn
ERROR: MethodError: no method matching jldopen(::Symbol)
Closest candidates are:
  jldopen(::AbstractString) at /home/phuoc/.julia/v0.6/JLD2/src/JLD2.jl:286
  jldopen(::AbstractString, ::Bool, ::Bool, ::Bool) at /home/phuoc/.julia/v0.6/JLD2/src/JLD2.jl:201
  jldopen(::AbstractString, ::Bool, ::Bool, ::Bool, ::T<:Union{Type{IOStream}, Type{JLD2.MmapIO}}; compress, mmaparrays) where T<:Union{Type{IOStream}, Type{JLD2.MmapIO}} at /home/phuoc/.julia/v0.6/JLD2/src/JLD2.jl:201
  ...

[simonster]

If you don't give it variable names, the load macro needs to know the path to the filename at macro expansion time, since it needs to read the file to determine the variable names. But there could be a better error message for this.

[floswald]

yes I've been looking around for that ::Symbol as well before I realized that I need to provide a variable name.

[tk3369]

I just came across this issue. Is there any way to use the @load macros with a variable then?

[luboshanus]

After a lot of time spent by looking for a use of the @load with variables inside the name of a file, there is a way. Sorry, if this comment is too obvious but the solution was not that obvious for me.

# saving
for i in 1:2
	xx = zeros(2,2)
	@save "temp$i.jld2" xx
end

# loading
for i in 1:2
    @eval @load $("temp$i.jld2")
end

[JonasIsensee]

The above is also not a great option since it evals into global scope..
This might not work inside functions.

Generally I'd recommend to either use the jldopen or the FileIO load syntax.