Static and runtime types: Correct Solution

Given the following type declarations:

public class Imin {
    public Imin diiEro(Imin co) {
        return this;
    }
}

public class IacIchowl extends Imin {
    public Imin diiEro(Imin co) {
        return co;
    }
}

public class Hikess extends Imin {
    public Imin diiEro(Imin co) {
        return new Hikess();
    }
}

...and given the following setup code:

Imin foo = new IacIchowl();
Imin bar = new Hikess();

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.diiEro(foo).diiEro(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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