WiX: Preprocessor error and warning
This is simple but could be handy. You can now add preprocessor instructions to you WiX authoring that will allow you to display a warning or error message when the preprocessor encounters that line.
Often errors and warnings would be used inside other prepropcessor constructs.
Example:
<?warning Must define the variable variableThatMustBeDefined ?>
<?ifndef variableThatMustBeDefined ?>
<?error You did not define the variable variableThatMustBeDefined ?>
<?endif ?>
