if the following are true:

• expression state at time 74 = "iterate_args"
• arguments stack at time 74 = [ [ 5, [ ] ], [ ] ]
• parent stack at time 74 = [ self."y" = 5, [ ] ]

then parent stack at time 75 = [ self."y" = 5, [ ] ]

Start from the conclusion and work back up the proof. Click the arrow to show the parents.