Quantified Constraint Handling Rules
This addresses a bottleneck in modeling PSPACE problems as finite two-player games for researchers in constraint programming, though it appears incremental as it builds on the QCSP framework.
The paper tackled the limitation of static binders in Quantified Constraint Satisfaction Problems (QCSP) by introducing Quantified Constraint Handling Rules (QCHR), which allow dynamic binder construction during solving, resulting in state-of-the-art performance for static binders and outperforming previous QCSP approaches for dynamic binders.
We shift the QCSP (Quantified Constraint Satisfaction Problems) framework to the QCHR (Quantified Constraint Handling Rules) framework by enabling dynamic binder and access to user-defined constraints. QCSP offers a natural framework to express PSPACE problems as finite two-players games. But to define a QCSP model, the binder must be formerly known and cannot be built dynamically even if the worst case won't occur. To overcome this issue, we define the new QCHR formalism that allows to build the binder dynamically during the solving. Our QCHR models exhibit state-of-the-art performances on static binder and outperforms previous QCSP approaches when the binder is dynamic.