Revert 2a2b94a..9cc5997

This rolls back to commit 2a2b94afe1c0db5517d7a0a76c4f4c406a6c5463.
Revert 9cc5997..5402cce

This rolls back to commit 9cc59979473f0111471685400409b6662a111624.
Interface and class definitions
Interface and class definitions
Interface and class definitions
Definitions
Header comment