Factoring out return.
More prims.
Remove s relation.
Moving folds to semantic files.
Hash lang for heap PCF.
Syntax bindings for new prims.
Hash lang for SPCF with heap.
Fix typing relation used for SPCF with heap.
Hash lang for CPCF with heap.
Hash lang for SCPCF with heap.
Use correct semantics in CPCF with heap hash lang.
Pretty print for heap.
Last minute tweaks.