@end
{endcode}
+With this configuration, a job that is submitted with a requirements statement like
+
+{code}
+Requirements = OpSysMajorVer == 7
+{endcode}
+
+is not changed at all, and only matches to a machine that runs EL7, but a job with no such clause has the requirements expression changed to look like
+
+{code}
+Requirements = (Target.OpSysMajorVer == 6) && ...
+AmTransformed = true
+{endcode}
+
+
Note that relying on a regexp match of an UnParse is suboptimal. We can then implement in 8.7.x a classad ContainsAttr function that returns true iff the expression references (directly or indirectly) some named attribute. This would make the code more robust and simpler.
These expressions simplify the Requirements expression, and obey the principle of least surprise for our users -- when they request a OpSysMajorVer, no changes are made to their requirements.
