Rule processing caveats

Follow these guidelines to help your rules process efficiently:

• Use the documented helper functions to reduce your need to loop through repeating instances when performing certain matching and compare operations on data. This improves your rule performance.
• Use generic Javascript functions under ECMAScript 5. For example, you can process an array of elements with filter( ), reduce( ), and so forth to loop through an array for a specific purpose. This can simplify your coding.

Javascript limitations

The following common Javascript and HTML coding operations are not allowed in any rule expressions:

• Console operations
• Print operations
• File operations (such as load( ) and open( ))
• DOM manipulations (such as document and window)
• Display messages (such as alert)
• Interrupting script processing (such as exit( ) and quit( ))
• Debugger commands
• Looping operations (such as for and while)
• Words internally restricted by the Rules engine:
  • Expression
  • Window

There are also some reserved words that are typically not allowed in JavaScript. For a complete list, see JavaScript Reserved Words.