closure.jl

julia> Meta.@lower function f()
           if true
           end
           r = 1
           cb = ()->r
           cb()
       end
:($(Expr(:thunk, CodeInfo(:(begin
      $(Expr(:method, :f))
      $(Expr(:thunk, CodeInfo(:(begin
      global ##9#10
      const ##9#10
      $(Expr(:struct_type, Symbol("##9#10"), :((Core.svec)()), :((Core.svec)(:r)), :(Core.Function), :((Core.svec)(Core.Box)), false, 1))
      return
  end))))
      Core.SSAValue(0) = (Core.svec)(##9#10)
      Core.SSAValue(1) = (Core.svec)()
      Core.SSAValue(2) = (Core.svec)(Core.SSAValue(0), Core.SSAValue(1))
      $(Expr(:method, false, Core.SSAValue(2), CodeInfo(:(begin
      #= REPL[2]:5 =#
      Core.SSAValue(0) = (Core.getfield)(#self#, :r)
      Core.SSAValue(1) = (Core.isdefined)(Core.SSAValue(0), :contents)
      unless Core.SSAValue(1) goto 6
      goto 9
      6:
      Core.NewvarNode(:(r))
      r
      9:
      Core.SSAValue(2) = (Core.getfield)(Core.SSAValue(0), :contents)
      return Core.SSAValue(2)
  end))))
      Core.SSAValue(3) = (Core.Typeof)(f)
      Core.SSAValue(4) = (Core.svec)(Core.SSAValue(3))
      Core.SSAValue(5) = (Core.svec)()
      Core.SSAValue(6) = (Core.svec)(Core.SSAValue(4), Core.SSAValue(5))
      $(Expr(:method, :f, Core.SSAValue(6), CodeInfo(:(begin
      #= REPL[2]:2 =#
      Core.NewvarNode(:(#9))
      r = (Core.Box)()
      Core.NewvarNode(:(cb))
      unless true goto 7
      #= line 3 =#
      7:
      #= line 4 =#
      (Core.setfield!)(r, :contents, 1)
      #= line 5 =#
      #9 = $(Expr(:new, Symbol("##9#10"), :(r)))
      cb = #9
      #= line 6 =#
      Core.SSAValue(0) = (cb)()
      return Core.SSAValue(0)
  end))))
      return f
  end)))))