How to get backtrace of `@async` Task

General Usage
5

This is an old topic, but I have the very same issue with async tasks: they don’t show a useful stacktrace be default. Not only @async itself, but also e.g. asyncmap:

asyncmap(0:10) do i
    1 ÷ i
end

ERROR: DivideError: integer division error
Stacktrace:
 [1] (::Base.var"#770#772")(::Task) at ./asyncmap.jl:178
 [2] foreach(::Base.var"#770#772", ::Array{Any,1}) at ./abstractarray.jl:2009
 [3] maptwice(::Function, ::Channel{Any}, ::Array{Any,1}, ::UnitRange{Int64}) at ./asyncmap.jl:178
 [4] wrap_n_exec_twice at ./asyncmap.jl:154 [inlined]
 [5] #async_usemap#755 at ./asyncmap.jl:103 [inlined]
 [6] #asyncmap#754 at ./asyncmap.jl:81 [inlined]
 [7] asyncmap(::Function, ::UnitRange{Int64}) at ./asyncmap.jl:81
 [8] top-level scope at REPL[3]:1

compare to map:

map(0:10) do i
    1 ÷ i
end

ERROR: DivideError: integer division error
Stacktrace:
 [1] div at ./int.jl:260 [inlined]
 [2] #13 at ./REPL[4]:2 [inlined]
 [3] iterate at ./generator.jl:47 [inlined]
 [4] _collect(::UnitRange{Int64}, ::Base.Generator{UnitRange{Int64},var"#13#14"}, ::Base.EltypeUnknown, ::Base.HasShape{1}) at ./array.jl:699
 [5] collect_similar(::UnitRange{Int64}, ::Base.Generator{UnitRange{Int64},var"#13#14"}) at ./array.jl:628
 [6] map(::Function, ::UnitRange{Int64}) at ./abstractarray.jl:2162
 [7] top-level scope at REPL[4]:1

Is there any way to force the stacktrace go further than the asyncmap internals, i.e. to the actual user function? I can only imagine putting try ... catch ... end there manually.

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