Class ClassicCPP

object --+            
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      Base --+        
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       Current --+    
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           Classic --+
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                    ClassicCPP

A Classic Scanner subclass which takes into account the type of
bracketing used to include the file, and uses classic CPP rules
for searching for the files based on the bracketing.

Note that in order for this to work, the regular expression passed
to the constructor must return the leading bracket in group 0, and
the contained filename in group 1.