Programming in a Nutshell

Tom Kelliher, CS 102

Feb. 12, 2001

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Paper due Friday.

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Assignment

From Last Time

Discussion on a variety of technology issues.

Outline

1. Basic features of Javascript.

2. Javascript lab.

Coming Up

Spreadsheets.

Programming in a Nutshell

1. A very primitive language, English-like but adapted for the computer.

2. High-level-language compiled to assembly language which is assembled to machine language (binary code).

3. A sequence of simple instructions (statements):
   1. Calculate this and store the result here.

      birthYear = currentYear - age - 1;
      

   2. Compare these two values.

      if (age >= 30)
         document.write("We can't trust you!<br><br>");
      else
         document.write("I wish I were young again!<br><br>");
      

4. Basic constructs:
   1. Straight-line execution.

   2. Conditional execution.

   3. Repetitive execution --- loops.

      for (i = 1; i <= age; i = i + 1)
          document.write(i + "<br>");
      

   4. Communicating with the world --- input/output statements.

      name = prompt("What is your name?", "");
      document.write("Hello " + name + "!<br><br>");
      

      Output sent to the browser, so HTML tags can be used!