I am particularly interested in solutions to the problem that encapsulated search can depend on the order of evaluation.
According to [1], encapsulated search in PAKCS depends on the order of evaluation, while in MCC, it does not, but using it requires knowledge of the compiler implementation and it does not follow the Curry language specification. This was written in 2007, so it may of course be out of date now.
KiCS2 returns results from encapsulated search in the IO monad, but I do not understand why.
[1] Braßel and Huch, On a Tighter Integration of Functional and Logic Programming, Proc. APLAS 2007