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| module Main exposing (main) | |
| {- | |
| Can we make impossible state transtions impossible as impossible state can be impossible? | |
| An order has this state machine: Initial -> { Processing, Cancelled }, Processing -> {Cancelled, Shipping}, | |
| Shipping -> {Shipped, Lost}. So end states are Cancelled, Shipped and Lost. | |
| Let's see if can make the compiler catch when trying to cancel an order that is shipping. |