CaptureSet

A mapping where the type map is required to be a bijection. Parameters as in Mapped.

The result of subcapturing comparisons is an opaque type CompareResult.TYPE. This is either OK, indicating success, or another capture set, indicating failure. The failure capture set is the one that did not allow propagaton of elements into it.

The subclass of constant capture sets with given elements elems

A variable that is derived from some other variable via a map or filter.

A variable with elements given at any time as { x <- source.elems | !other.accountsFor(x) }

A variable with elements given at any time as { x <- source.elems | p(x) }

A special state that does not allow to record elements or dependent sets. In effect this means that no new elements or dependent sets can be added in this state (since the previous state cannot be recorded in a snapshot)

A TypeMap with the property that every capture reference in the image of the map is mapped to itself. I.e. for all capture references r1, r2, if M(r1) == r2 then M(r2) == r2.

A TypeMap that is the identity on capture references

A variable that changes when source changes, where all additional new elements are mapped using ∪ { tm(x) | x <- source.elems }.

The subclass of captureset variables with given initial elements

A VarState serves as a snapshot mechanism that can undo additions of elements or super sets if an operation fails

Extrapolate tm(r) according to variance. Let r1 be the result of tm(r).

• If r1 is a tracked CaptureRef, return {r1}
• If r1 has an empty capture set, return {}
• Otherwise,
  • if the variance is covariant, return r1's capture set
  • if the variance is contravariant, return {}
  • Otherwise assertion failure

Apply f to each element in xs, and join result sets with ++

Apply extrapolated tm to each element in xs, and join result sets with ++

The capture set of the type underlying a CaptureRef

Capture set of a type

Return true iff

• arg1 is a TypeBounds >: CL T <: CH T of two capturing types with equal parents.
• arg2 is a capturing type CA U
• CH <: CA <: CL In other words, we can unify CL, CH and CA.

The universal capture set {*}

The current VarState, as passed by the implicit context

Perform op. Under -Ycc-debug, collect and print info about all variables reachable via (_.deps)* from the variables that were shown in op.

The empty capture set {}