The OESmartsParseOpts namespace encodes symbolic constants used as bit-masks to indicate how to interpret SMARTS and SMIRKS strings.
This namespace contains constants.
Only constraints explicitly specified in the SMARTS and SMIRKS strings are added to the OEQMolBase query structure.
Additional ring constraint is added to each ring atom of the generated OEQMolBase query molecule.
This can significantly increase the performance of the substructure search. For example, matching the C1CCCCC1 ring against the CCCCCCCC chain will fail much faster, since none of the query ring atoms can be mapped to any of the target chain atom.
Same as the OESmartsParseOpts::RingConstraint constant.