Error: no method matching iterate(::Expr)

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macro superM(arg, argc)

    map(foo,argc)
end

@superM test {1,2}

I just want to passe the argument argc to the map function, but I'm getting this error: no method matching iterate(::Expr)

julia mapping macros
1 Answers

the argc is an Expression whose head is braces {}:

julia> dump(:({1, 2}))
Expr
  head: Symbol braces
  args: Array{Any}((2,))
    1: Int64 1
    2: Int64 2

so what you really want is the args field of the expression {1,2}

julia> macro superM(arg, argc)    
           map(identity,argc.args)
       end
@superM (macro with 1 method)

julia> @superM test {1,2}
2-element Vector{Int64}:
 1
 2
user_29606950
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