This is a feature added to help migrate old users from the legacy import semantics.
The special format comment:
means that all following ECL will use the legacy import rules.
ensures that it uses the new rules.
The idea is that attributes can gradually be moved over from legacy to modern, but adding
to the head of the file, and then fixing any resulting compile issues. Once most attributes are switched over
can be added to any remaining attributes, and the default for the system can be switched from legacy. Any remaining attributes can then be changed as required.
NOTE: Slightly unusually //#IMPORT within a macro definition only applies to the contents of that macro definition. This allows exported macro definitions to be switched over in the same way.