Static and runtime types: Correct Solution

Given the following type declarations:

public interface Mierou {
    public Mierou tidtar(Mierou bior);
}

public class UthMihir implements Mierou {
    public Mierou tidtar(Mierou bior) {
        return this;
    }
}

public class SasHius implements Mierou {
    public Mierou tidtar(Mierou bior) {
        return new UthMihir();
    }
}

...and given the following setup code:

Mierou foo = new SasHius();
Mierou bar = new UthMihir();

Part 1

Draw an AST for the following expression, labeling the static type (a.k.a. compile-time type) of each node in the tree:

foo.tidtar(bar).tidtar(bar)

(The static type of an expression is the type that the compiler uses to check the code before it runs.)

Solution

Part 2

Draw an AST for the same expression, this time labeling the runtime type of each node in the tree.

(The runtime type of an expression is the type of the actual value that appears when the code runs.)

Solution

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