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2.6.7 Comments

NOTE: This is NOT the latest copy of this book; click here for the latest version.

While in PHP mode, you can mark certain parts of your code as a comment that should not be executed. PHP has three ways of doing this: //, /* */, and #. // and # mean, "ignore the rest of this line", whereas /* means "ignore everything until you see */". Some complications exist with /* and */, though, which make them less desirable to use.

<?php

      print "This is printed\n";

      // print "This is not printed\n";

      # print "This is not printed\n";

      print "This is printed\n";

      /* print "This is not printed\n";

      print "This is not printed\n"; */
 ?>

That chunk of code shows all three types of comments in action, but does not demonstrate the problem with the /* */ form of commenting. If you were to start a /* comment on line one, and end it on the line near the bottom where the other /* comment is started, you would find that the script would fail to work. The reason for this is that you cannot stack up, or "nest" /* */ comments, and attempting to do so will usually fail spectacularly.

It is generally best to stick to // for your commenting purposes, simply because it is easier to spot, easy to read, and easy to keep control of.

<< 2.6.6 Opening and closing code islands		2.6.8 Conditional statements >>
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