Static and runtime types: Correct Solution

Given the following type declarations:

public class Leass {
    public Leass pestpi(Leass trol) {
        return trol;
    }
}

public class Pedfat extends Leass {
    public Leass pestpi(Leass trol) {
        return new Pedfat();
    }
}

public class Moorm extends Leass {
    public Leass pestpi(Leass trol) {
        return this;
    }
}

...and given the following setup code:

Leass foo = new Moorm();
Leass bar = new Pedfat();

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.pestpi(foo.pestpi(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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