9.5 Rules defined more than once

It can happen that a WML element is defined more than once in a WML file. When a WML element is defined more than once, the last definition supersedes all the preceding definitions. Here are some ways this happens:

• A rule is defined once in an include file and once in the WML file itself. The definition in the WML file supersedes the one in the include file. This is the most useful case: it enables you to use an include file, and to modify one or more of the rules that come from that include file.
• A single WML file contains three definitions of the same rule. The third definition supersedes the preceding ones.
• A rule is defined in two files that are included in this WML file. The definition in the last include file supersedes the definition in the preceding include file.
• A WML file includes the same WML file twice; in this case, all rules are repeated. The second set of definitions supersedes the first set (although there is no real effect, because both sets of definitions are the same).

WebMaker detects when a rule is defined more than once, and opens a dialog to inform you.