# FIXME: Add a 'is_valid_anchor' to improve imputability.
# Currently, anchors are used "as it" without check thus if the caller gives a
# bad anchor, then the method will likely crash (abort) in a bad case
-#
-# FIXME: maybe allways add an anchor with a nullable type (as in is_subtype)
abstract class MType
# The model of the type
if not need_anchor then return self
assert not anchor.need_anchor
# Just resolve to the anchor and clear all the virtual types
- var res = self.resolve_for(anchor, anchor, mmodule, true)
+ var res = self.resolve_for(anchor, null, mmodule, true)
assert not res.need_anchor
return res
end
#
# REQUIRE: `super_mclass' is a super-class of `self'
# ENSURE: return.mclass = mclass
- fun supertype_to(mmodule: MModule, anchor: MClassType, super_mclass: MClass): MClassType
+ fun supertype_to(mmodule: MModule, anchor: nullable MClassType, super_mclass: MClass): MClassType
do
if super_mclass.arity == 0 then return super_mclass.mclass_type
if self isa MClassType and self.mclass == super_mclass then return self
- var resolved_self = self.anchor_to(mmodule, anchor)
+ var resolved_self
+ if self.need_anchor then
+ assert anchor != null
+ resolved_self = self.anchor_to(mmodule, anchor)
+ else
+ resolved_self = self
+ end
var supertypes = resolved_self.collect_mtypes(mmodule)
for supertype in supertypes do
if supertype.mclass == super_mclass then
#
# This function returns self if `need_anchor' is false.
#
- # Example:
+ # ## Example 1
+ #
# class G[E]
# class H[F] super G[F]
- # Array[E] resolve_for H[Int] #-> Array[Int]
+ # class X[Z]
+ #
+ # Array[E].resolve_for(H[Int]) #-> Array[Int]
+ # Array[E].resolve_for(G[Z], X[Int]) #-> Array[Z]
#
# Explanation of the example:
# * Array[E].need_anchor is true because there is a formal generic
# * So, in H[Int], Array[E] is Array[Int]
#
# This function is mainly used to inherit a signature.
- # Because, unlike `anchor_type', we do not want a full resolution of
+ # Because, unlike `anchor_to', we do not want a full resolution of
# a type but only an adapted version of it.
#
- # Example:
+ # ## Example 2
+ #
# class A[E]
# foo(e:E):E
# end
# The signature on foo is (e: E): E
# If we resolve the signature for B, we get (e:Int):Int
#
+ # ## Example 3
+ #
+ # class A[E]
+ # fun foo(e:E) is abstract
+ # end
+ # class B[F]
+ # var a: A[Array[F]]
+ # fun bar do a.foo(x) # <- x is here
+ # end
+ #
+ # The first question is: is foo available on `a`?
+ #
+ # The static type of a is `A[Array[F]]`, that is an open type.
+ # in order to find a method `foo`, whe must look at a resolved type.
+ #
+ # A[Array[F]].anchor_to(B[nullable Object]) #-> A[Array[nullable Object]]
+ #
+ # the method `foo` exists in `A[Array[nullable Object]]`, therefore `foo` exists for `a`.
+ #
+ # The next question is: what is the accepted types for `x'?
+ #
+ # the signature of `foo` is `foo(e:E)`, thus we must resolve the type E
+ #
+ # E.resolve_for(A[Array[F]],B[nullable Object]) #-> Array[F]
+ #
# TODO: Explain the cleanup_virtual
#
# FIXME: the parameter `cleanup_virtual' is just a bad idea, but having
# two function instead of one seems also to be a bad idea.
#
+ # REQUIRE: can_resolve_for(mtype, anchor, mmodule)
# ENSURE: not self.need_anchor implies return == self
- fun resolve_for(mtype: MType, anchor: MClassType, mmodule: MModule, cleanup_virtual: Bool): MType is abstract
+ fun resolve_for(mtype: MType, anchor: nullable MClassType, mmodule: MModule, cleanup_virtual: Bool): MType is abstract
# Return the nullable version of the type
# If the type is already nullable then self is returned
return super.as(MClassType)
end
- redef fun resolve_for(mtype: MType, anchor: MClassType, mmodule: MModule, cleanup_virtual: Bool): MClassType do return self
+ redef fun resolve_for(mtype: MType, anchor: nullable MClassType, mmodule: MModule, cleanup_virtual: Bool): MClassType do return self
redef fun collect_mclassdefs(mmodule)
do
# The point of the function it to get the bound of the virtual type that make sense for mtype
# But because mtype is maybe a virtual/formal type, we need to get a real receiver first
#print "{class_name}: {self}/{mtype}/{anchor}?"
- var resolved_reciever = mtype.resolve_for(anchor, anchor, mmodule, true)
+ var resolved_reciever
+ if mtype.need_anchor then
+ assert anchor != null
+ resolved_reciever = mtype.resolve_for(anchor, null, mmodule, true)
+ else
+ resolved_reciever = mtype
+ end
# Now, we can get the bound
var verbatim_bound = lookup_bound(mmodule, resolved_reciever)
# The bound is exactly as declared in the "type" property, so we must resolve it again
# The point of the function it to get the bound of the virtual type that make sense for mtype
# But because mtype is maybe a virtual/formal type, we need to get a real receiver first
# FIXME: What happend here is far from clear. Thus this part must be validated and clarified
- var resolved_receiver = mtype.resolve_for(anchor.mclass.mclass_type, anchor, mmodule, true)
+ var resolved_receiver
+ if mtype.need_anchor then
+ assert anchor != null
+ resolved_receiver = mtype.resolve_for(anchor.mclass.mclass_type, anchor, mmodule, true)
+ else
+ resolved_receiver = mtype
+ end
if resolved_receiver isa MNullableType then resolved_receiver = resolved_receiver.mtype
if resolved_receiver isa MParameterType then
assert resolved_receiver.mclass == anchor.mclass
resolved_receiver = anchor.arguments[resolved_receiver.rank]
if resolved_receiver isa MNullableType then resolved_receiver = resolved_receiver.mtype
end
- assert resolved_receiver isa MClassType else print "{class_name}: {self}/{mtype}/{anchor}? {resolved_receiver}"
+ assert resolved_receiver isa MClassType
# Eh! The parameter is in the current class.
# So we return the corresponding argument, no mater what!
return res
end
- resolved_receiver = resolved_receiver.resolve_for(anchor, anchor, mmodule, false)
+ if resolved_receiver.need_anchor then
+ assert anchor != null
+ resolved_receiver = resolved_receiver.resolve_for(anchor, null, mmodule, false)
+ end
# Now, we can get the bound
var verbatim_bound = lookup_bound(mmodule, resolved_receiver)
# The bound is exactly as declared in the "type" property, so we must resolve it again
return b.to_s
end
- redef fun resolve_for(mtype: MType, anchor: MClassType, mmodule: MModule, cleanup_virtual: Bool): MSignature
+ redef fun resolve_for(mtype: MType, anchor: nullable MClassType, mmodule: MModule, cleanup_virtual: Bool): MSignature
do
var params = new Array[MParameter]
for p in self.mparameters do
# Is the parameter a vararg?
var is_vararg: Bool
- fun resolve_for(mtype: MType, anchor: MClassType, mmodule: MModule, cleanup_virtual: Bool): MParameter
+ fun resolve_for(mtype: MType, anchor: nullable MClassType, mmodule: MModule, cleanup_virtual: Bool): MParameter
do
if not self.mtype.need_anchor then return self
var newtype = self.mtype.resolve_for(mtype, anchor, mmodule, cleanup_virtual)
nitlanguage / nit.git / commitdiff