Variables
  #self#[36m::Core.Const(Main.anonymous.foo)[39m
  x[36m::Int64[39m
  y[36m::Int64[39m
  #1[36m::Main.anonymous.var"#1#2"[39m
  v[36m::Union{}[39m
  u[91m[1m::Any[22m[39m
  z@_7[91m[1m::Core.Box[22m[39m
  z@_8[36m::Union{}[39m
  z@_9[36m::Union{}[39m
  z@_10[36m::Union{}[39m

│ ─ %-1  = invoke foo(::Int64,::Int64)::Union{}
[90m│   [39m       (z@_7 = Core.Box())[90m::Core.Box[39m
[90m5 ┄─[39m %12 = Core.getfield(z@_7, :contents)[36m::Any[39m
[90m│   [39m %13 = (%12 < 4)[36m::Any[39m
[90m9 ┄─[39m %20 = Core.getfield(z@_7, :contents)[36m::Any[39m
[90m│   [39m %21 = (%20 + 1)[36m::Any[39m
[90m│   [39m       (u = (%25)(x))[90m::Any[39m
