# UndefVarError: writeshortest not defined with JSON3

**URL:** <https://discourse.julialang.org/t/undefvarerror-writeshortest-not-defined-with-json3/93893>\
**Category:** New to Julia\
**Tags:** question\
**Created:** [February 1, 2023, 10:15pm UTC](https://discourse.julialang.org/t/undefvarerror-writeshortest-not-defined-with-json3/93893 "2023-02-01T22:15:30Z")\
**Posts on this page:** 5\
**Page:** 1

<div class="post-metadata">

**Author:** ![Davidfloor](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/davidfloor/32/46449_2.png) [@Davidfloor](https://discourse.julialang.org/u/Davidfloor)\
**Post date:** [February 1, 2023, 10:15pm UTC](https://discourse.julialang.org/t/undefvarerror-writeshortest-not-defined-with-json3/93893/1 "2023-02-01T22:15:30Z")

</div>

Hi,  
I use below code to write json file but it shows UndefVarError: writeshortest not defined. Please help me solve this problem! Thank you!

```julia
h5open(solution, "r") do f
    t = open_dataset(f, "t")[:]
    v = open_dataset(f, "v")
    maxv_l = similar(t)
    maxv_r = similar(t)
    @showprogress "Iterating max velocity" for i ∈ range(1, length=length(t))
        v_tmp = v[:,:,i]
        maxv_l[i] = maximum(v_tmp[patch_l])
        maxv_r[i] = maximum(v_tmp[patch_r])
    end

    content = Dict(
        :t => t,
        :maxv_l => maxv_l,
        :maxv_r => maxv_r,
    )
    open(catalog, "w") do io
        JSON3.write(io, content)
    end

```

The error is below,

UndefVarError: writeshortest not defined

Stacktrace:  
[1] getproperty  
@ .\Base.jl:35 [inlined]  
[2] write(::StructTypes.NumberType, buf::Vector{UInt8}, pos::Int64, len::Int64, x::Float64; allow\_inf::Bool, kw::Base.Pairs{Symbol, Union{}, Tuple{}, NamedTuple{(), Tuple{}}})  
@ JSON3 C:\Users\student.julia\packages\JSON3\GoF7x\src\write.jl:236  
[3] write  
@ C:\Users\student.julia\packages\JSON3\GoF7x\src\write.jl:225 [inlined]  
[4] write(::StructTypes.ArrayType, buf::Vector{UInt8}, pos::Int64, len::Int64, x::Vector{Float64}; kw::Base.Pairs{Symbol, Union{}, Tuple{}, NamedTuple{(), Tuple{}}})  
@ JSON3 C:\Users\student.julia\packages\JSON3\GoF7x\src\write.jl:169  
[5] write(::StructTypes.ArrayType, buf::Vector{UInt8}, pos::Int64, len::Int64, x::Vector{Float64})  
@ JSON3 C:\Users\student.julia\packages\JSON3\GoF7x\src\write.jl:165  
[6] write(::StructTypes.DictType, buf::Vector{UInt8}, pos::Int64, len::Int64, x::Dict{Symbol, Vector{Float64}}; kw::Base.Pairs{Symbol, Union{}, Tuple{}, NamedTuple{(), Tuple{}}})  
@ JSON3 C:\Users\student.julia\packages\JSON3\GoF7x\src\write.jl:155  
[7] write  
@ C:\Users\student.julia\packages\JSON3\GoF7x\src\write.jl:146 [inlined]  
[8] write(io::IOStream, obj::Dict{Symbol, Vector{Float64}}; kw::Base.Pairs{Symbol, Union{}, Tuple{}, NamedTuple{(), Tuple{}}})  
@ JSON3 C:\Users\student.julia\packages\JSON3\GoF7x\src\write.jl:32  
[9] write  
@ C:\Users\student.julia\packages\JSON3\GoF7x\src\write.jl:30 [inlined]  
[10] #266  
@ .\In[29]:31 [inlined]  
[11] open(::var"#266#268"{Dict{Symbol, Vector{Float64}}}, ::String, ::Vararg{String}; kwargs::Base.Pairs{Symbol, Union{}, Tuple{}, NamedTuple{(), Tuple{}}})  
@ Base .\io.jl:330  
[12] open(::Function, ::String, ::String)  
@ Base .\io.jl:328  
[13] (::var"#265#267")(f::HDF5.File)  
@ Main .\In[29]:30  
[14] h5open(::var"#265#267", ::String, ::Vararg{String}; swmr::Bool, pv::Base.Pairs{Symbol, Union{}, Tuple{}, NamedTuple{(), Tuple{}}})  
@ HDF5 C:\Users\student.julia\packages\HDF5\I9NLZ\src\HDF5.jl:303  
[15] h5open(::Function, ::String, ::String)  
@ HDF5 C:\Users\student.julia\packages\HDF5\I9NLZ\src\HDF5.jl:301  
[16] top-level scope  
@ In[29]:14  
[17] eval  
@ .\boot.jl:373 [inlined]  
[18] include\_string(mapexpr::typeof(REPL.softscope), mod::Module, code::String, filename::String)  
@ Base .\loading.jl:1196

---

<div class="post-metadata">

**Author:** ![nilshg](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/nilshg/32/2283_2.png) [@nilshg](https://discourse.julialang.org/u/nilshg)\
**Post date:** [February 2, 2023, 9:33am UTC](https://discourse.julialang.org/t/undefvarerror-writeshortest-not-defined-with-json3/93893/2 "2023-02-02T09:33:33Z")

</div>

Probably a Parsers versioning issue, what’s your `st` and `st -m`? Also do you get the same issue when writing a simpler file (in other words, can you make your code snippet a self contained MWE by just writing out some dummy data)?

---

<div class="post-metadata">

**Author:** ![Davidfloor](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/davidfloor/32/46449_2.png) [@Davidfloor](https://discourse.julialang.org/u/Davidfloor)\
**Post date:** [February 2, 2023, 5:04pm UTC](https://discourse.julialang.org/t/undefvarerror-writeshortest-not-defined-with-json3/93893/3 "2023-02-02T17:04:44Z")

</div>

Hi nilshg,

My complete code is like this.

```julia
begin
    using PyCall, PyPlot, Oetqf, JSON3, JLD2, ProgressMeter
    include(joinpath(@ __DIR__ , "utils.jl"))
end

solution = joinpath(@ __DIR__ , "output.h5")
catalog = joinpath(@ __DIR__ , "catalog.json")

mf = load(joinpath(@ __DIR__ , "mesh.jld2"), "fault")
patch_l = (@. -485e3 .≤ mf.x .≤ -85e3) .* (@. -17.5e3 .≤ mf.z .≤ -2.5e3)'
patch_r = (@. 85e3 .≤ mf.x .≤ 485e3) .* (@. -17.5e3 .≤ mf.z .≤ -2.5e3)'
μ = 30e9

h5open(solution, "r") do f
    t = open_dataset(f, "t")[:]
    v = open_dataset(f, "v")
    maxv_l = similar(t)
    maxv_r = similar(t)
    @showprogress "Iterating max velocity" for i ∈ range(1, length=length(t))
        v_tmp = v[:,:,i]
        maxv_l[i] = maximum(v_tmp[patch_l])
        maxv_r[i] = maximum(v_tmp[patch_r])
    end

    content = Dict(
        :t => t,
        :maxv_l => maxv_l,
        :maxv_r => maxv_r,
    )
    open(catalog, "w") do io
        JSON3.write(io, content)
    end

```

t is time parameter. I think it’s not the problem of JSON3. Could be read and write data into “content” dictionary. Can you help me optimize this?

---

<div class="post-metadata">

**Author:** ![nilshg](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/nilshg/32/2283_2.png) [@nilshg](https://discourse.julialang.org/u/nilshg)\
**Post date:** [February 2, 2023, 6:07pm UTC](https://discourse.julialang.org/t/undefvarerror-writeshortest-not-defined-with-json3/93893/4 "2023-02-02T18:07:39Z")

</div>

But your stacktrace explicitly points to `write`, and these `writeshortest` errors pop up frequently (I’ve seen them loads in CSV.jl) when there’s a version mismatch.

Therefor I will repeat my questions:

- What is your `st` and `st -m`?
- Can you write out something simple like `JSON3.write("test.json", (x = rand('a':'z', 100), y = rand(100)))`

---

<div class="post-metadata">

**Author:** ![Davidfloor](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/davidfloor/32/46449_2.png) [@Davidfloor](https://discourse.julialang.org/u/Davidfloor)\
**Post date:** [February 2, 2023, 6:23pm UTC](https://discourse.julialang.org/t/undefvarerror-writeshortest-not-defined-with-json3/93893/5 "2023-02-02T18:23:01Z")

</div>

My string is data like this:

Dict(:maxv\_r =\> [1.0147133434804667e-9, 1.796118473731384e-9, 7.57657124507717e-9, 1.0231846445183663e-8, 1.1349013697680884e-8, 1.3167898562992613e-8, 1.49972231762508e-8, 1.4435121588935785e-8, 1.3176734564674757e-8, 1.2394497977361867e-8, 1.1686529120019848e-8, 1.1186273697127198e-8, 1.0954811066070923e-8, 1.081808008533313e-8, 1.0769229656071547e-8, 1.0756597593374443e-8, 1.0752271415084019e-8, 1.0750580284202741e-8, 1.0749215131461214e-8, 1.0747894234025832e-8, 1.0746321796440239e-8, 1.0744949619617457e-8, 1.0743867673829676e-8, … 7.598747648583915e8, 7.598747863885643e8, 7.598748000376701e8, 7.598748077412821e8, 7.598748131626374e8, 7.598748172228965e8, 7.598748206474913e8, 7.598748236435429e8, 7.598748260265518e8, 7.598748300485772e8, 7.598748323579266e8])  
I am not sure how to know my st -m.  
And if I do dummy data like below, there is no error.

people = [Dict(“name”=\>“CoolGuy”, “company”=\>“tech”) for i=1:1000]  
companies = [Dict(“name”=\>“CoolTech”, “address”=\>“Bay Area”) for i=1:100]  
data = Dict(“people”=\>people, “companies”=\>companies)

open(catalog,“w”) do f  
JSON3.write(f, data)  
end