Chapter 3, exercises 1 & 2

---
// DemonstratePrecedence.java
// chapter 3, exercise 1
class DemonstratePrecedence {
  public static void main(String[] args) {
    int a, x, y, z;
    x = 1;
    y = 2;
    z = 3;
    a = x + y - 2/2 + z;
    System.out.println( "a is " + a );
    a = x + (y - 2) / (2 + z);
    System.out.println( "a is " + a );
  }
}
---

Chapter 3, ex 1, Lisp version

---
;;;; chapter 3, ex 1
(defun demonstrate-precedence ()
  "Not really much point to this one, since Lisp doesn't actually HAVE precedence,
  but I'll do it anyway."
  (let (a
	(x 1)
	(y 2)
	(z 3))
    (setf a (+ x y z (- (/ 2 2))))
    (format t "a is ~a~%" a)
    (setf a (+ x (/ (- y 2) (+ 2 z))))
    (format t "a is ~a~%" a)))
---

09:07 -- starting 3.2, Java version
09:11 -- done

---
// ch3_ex2.java
// chapter 3, exercise 2
class ch3_ex2 {
  static int ternary( int i ) {
    return i < 10 ? i * 100 : i * 10;
  }
  static int alternative( int i ) {
    if (i < 10)
      return i * 100;
    else
      return i * 10;
  }
  public static void main( String[] args ) {
    ternary( 9 );
    // this one goes to 11
    alternative( 11 );
  }
}
---

09:12 -- starting 3.2, Lisp version
09:17 -- done

---
;;;; chapter 2, ex 2
(defun ternary (i)
  ;;; could use flet for ternary and alternative, actually
  (if (< i 10) (* i 100) (* i 10)))
(defun alternative (i)
  (cond ((< i 10) (* i 100))
	(t (* i 10))))
(ternary 9)
(alternative 11)
---

At first I did ternary and alternative exactly the same, but did the "if" on one line in ternary and on three in alternative, just to be a smartass. ;) But I changed my mind and modified it a bit.

As with many of these exercises so far, the "do this just to get a feeling for the language" spirit of the exercise doesn't really translate well from Java to Lisp, at least to me.

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