Reducer
A type map that tries to reduce (part of) the result type of the type lambda tycon
with the given args
(some of which are wildcard arguments represented by type bounds). Non-wildcard arguments are substituted everywhere as usual. A wildcard argument >: L <: H
is substituted for a type lambda parameter X
only under certain conditions.
-
If Mode.AllowLambdaWildcardApply is set: The wildcard argument is substituted only if
X
appears in a toplevel application of the formC[..., X, ...]
and there are no other occurrences of X
in the reduced type. In that case the refinement above is replaced by
C[..., ? >: L <: H, ...]
The allReplaced
field indicates whether all occurrences of type lambda parameters in the reduced type have been replaced with arguments.
-
If Mode.AllowLambdaWildcardApply is not set: All
X
arguments are replaced by:? >: L <: H
Any other occurrence of X
in tycon
is replaced by U
, if the occurrence of X
in tycon
is covariant, or nonvariant, or by L
, if the occurrence is contravariant.
The idea is that the AllowLambdaWildcardApply
mode is used to check whether a type can be soundly reduced, and to give an error or warning if that is not the case. By contrast, the default mode, with AllowLambdaWildcardApply
not set, reduces all applications even if this yields a different type, so its postcondition is that no type parameters of tycon
appear in the result type. Using this mode, we can guarantee that appliedTo
will never produce a higher-kinded application with a type lambda as type constructor.
Attributes
- Graph
-
- Supertypes
Members list
Value members
Concrete methods
Inherited methods
Attributes
- Inherited from:
- VariantTraversal
Attributes
- Inherited from:
- TypeMap
Attributes
- Inherited from:
- TypeMap
Attributes
- Inherited from:
- TypeMap
Attributes
- Inherited from:
- TypeMap
Attributes
- Inherited from:
- TypeMap
Attributes
- Inherited from:
- TypeMap
Attributes
- Inherited from:
- TypeMap
Attributes
- Inherited from:
- TypeMap
Attributes
- Inherited from:
- TypeMap
Attributes
- Inherited from:
- TypeMap
Attributes
- Inherited from:
- TypeMap
Attributes
- Inherited from:
- TypeMap
Attributes
- Inherited from:
- TypeMap
Attributes
- Inherited from:
- TypeMap
Attributes
- Inherited from:
- TypeMap
Attributes
- Inherited from:
- TypeMap
Attributes
- Inherited from:
- TypeMap
Attributes
- Inherited from:
- TypeMap
Can the prefix of this static reference be omitted if the reference itself can be omitted? Overridden in TypeOps#avoid.
Can the prefix of this static reference be omitted if the reference itself can be omitted? Overridden in TypeOps#avoid.
Attributes
- Inherited from:
- VariantTraversal
Attributes
- Inherited from:
- TypeMap
Attributes
- Inherited from:
- TypeMap
Can be overridden. By default, only the prefix is mapped.
Map this function over given type
Attributes
- Inherited from:
- TypeMap
Attributes
- Inherited from:
- VariantTraversal
Attributes
- Inherited from:
- VariantTraversal
The type parameters of the constructor of this applied type. Overridden in OrderingConstraint's ConstraintAwareTraversal to take account of instantiations in the constraint that are not yet propagated to the instance types of type variables.
The type parameters of the constructor of this applied type. Overridden in OrderingConstraint's ConstraintAwareTraversal to take account of instantiations in the constraint that are not yet propagated to the instance types of type variables.
Attributes
- Inherited from:
- VariantTraversal