By default this code keeps the same behavior that it had before. It is only if you say something like:

    <all-programs regex="true">

or:

    <program name="foo.c" regex="true">

That this change takes effect. In fact, it makes our tests stronger and _less_ fragile to use this in cases where we are comparing krun output configurations and search results. By using regular expressions in the form I demonstrate in these examples, we are able to make the test not depend on the syntactic representation of fresh variables, on the ordering of search results within the resulting program, or on the precise wording of KRun's output headers. Instead it provides an extremely powerful syntax for specifying precisely what you do or don't care about in the output of krun.

If you approve of my reasoning, I will make sure to add a line to document this in the manual before I merge this. But this will probably be needed in the long term anyway in the tutorial because the Java and Maude backends cannot be guaranteed to generate identical representations of fresh variables or the ordering of search results.