workingworlds.jl

julia> f(x) = println("hello")
f (generic function with 1 method)

julia> callf(x) = f(x)
callf (generic function with 1 method)

julia> const callf_lowered = @code_lowered callf(1)
CodeInfo(:(begin
      nothing
      Core.SSAValue(0) = (Main.f)(x)
      return Core.SSAValue(0)
  end))

julia> @generated function g(x)
           return deepcopy(callf_lowered)
       end
g (generic function with 1 method)

julia> g(1)
hello

julia> f(x::Int) = println("goodbye")
f (generic function with 2 methods)

julia> g(1)
goodbye

julia> f(1)
goodbye

julia> f(1.0)
hello

julia> g(1.0)
hello