# The only null type
var null_type = new MNullType(self)
+ # The only bottom type
+ var bottom_type: MBottomType = null_type.as_notnull
+
# Build an ordered tree with from `concerns`
fun concerns_tree(mconcerns: Collection[MConcern]): ConcernsTree do
var seen = new HashSet[MConcern]
# The primitive type `String`
var string_type: MClassType = self.get_primitive_class("String").mclass_type is lazy
- # The primitive type `NativeString`
- var native_string_type: MClassType = self.get_primitive_class("NativeString").mclass_type is lazy
+ # The primitive type `CString`
+ var c_string_type: MClassType = self.get_primitive_class("CString").mclass_type is lazy
# A primitive type of `Array`
fun array_type(elt_type: MType): MClassType do return array_class.get_mtype([elt_type])
# ENSURE: `bound_mtype.mclass == self.mclass`
var bound_mtype: MClassType
- redef var location: Location
+ redef var location
redef fun visibility do return mclass.visibility
end
#print "4.is {sub} a {sup}? <- no more resolution"
- if sub isa MBottomType then
+ if sub isa MBottomType or sub isa MErrorType then
return true
end
assert sub isa MClassType else print_error "{sub} <? {sup}" # It is the only remaining type
# Handle sup-type when the sub-type is class-based (other cases must have be identified before).
- if sup isa MFormalType or sup isa MNullType or sup isa MBottomType then
+ if sup isa MFormalType or sup isa MNullType or sup isa MBottomType or sup isa MErrorType then
# These types are not super-types of Class-based types.
return false
end
#
# Explanation of the example:
# In H, T is set to B, because "H super G[B]", and U is bound to Y,
- # because "redef type U: Y". Therefore, Map[T, U] is bound to
+ # because "redef type U: Y". Therefore, Map[T, U] is bound to
# Map[B, Y]
#
+ # REQUIRE: `self.need_anchor implies anchor != null`
# ENSURE: `not self.need_anchor implies result == self`
# ENSURE: `not result.need_anchor`
- fun anchor_to(mmodule: MModule, anchor: MClassType): MType
+ fun anchor_to(mmodule: MModule, anchor: nullable MClassType): MType
do
if not need_anchor then return self
- assert not anchor.need_anchor
+ assert anchor != null and not anchor.need_anchor
# Just resolve to the anchor and clear all the virtual types
var res = self.resolve_for(anchor, null, mmodule, true)
assert not res.need_anchor
# The result is returned exactly as declared in the "type" property (verbatim).
# So it could be another formal type.
#
- # In case of conflicts or inconsistencies in the model, the method returns a `MBottomType`.
+ # In case of conflicts or inconsistencies in the model, the method returns a `MErrorType`.
fun lookup_bound(mmodule: MModule, resolved_receiver: MType): MType do return self
# Resolve the formal type to its simplest equivalent form.
# By default, return self.
# See the redefinitions for specific behavior in each kind of type.
#
- # In case of conflicts or inconsistencies in the model, the method returns a `MBottomType`.
+ # In case of conflicts or inconsistencies in the model, the method returns a `MErrorType`.
fun lookup_fixed(mmodule: MModule, resolved_receiver: MType): MType do return self
+ # Is the type a `MErrorType` or contains an `MErrorType`?
+ #
+ # `MErrorType` are used in result with conflict or inconsistencies.
+ #
+ # See `is_legal_in` to check conformity with generic bounds.
+ fun is_ok: Bool do return true
+
+ # Is the type legal in a given `mmodule` (with an optional `anchor`)?
+ #
+ # A type is valid if:
+ #
+ # * it does not contain a `MErrorType` (see `is_ok`).
+ # * its generic formal arguments are within their bounds.
+ fun is_legal_in(mmodule: MModule, anchor: nullable MClassType): Bool do return is_ok
+
# Can the type be resolved?
#
# In order to resolve open types, the formal types must make sence.
# * H[G[A], B] -> 3
#
# Formal types have a depth of 1.
+ # Only `MClassType` and `MFormalType` nodes are counted.
fun depth: Int
do
return 1
# * H[G[A], B] -> 4
#
# Formal types have a length of 1.
+ # Only `MClassType` and `MFormalType` nodes are counted.
fun length: Int
do
return 1
redef fun need_anchor do return false
- redef fun anchor_to(mmodule: MModule, anchor: MClassType): MClassType
+ redef fun anchor_to(mmodule, anchor): MClassType
do
return super.as(MClassType)
end
return true
end
+ redef fun is_ok
+ do
+ for t in arguments do if not t.is_ok then return false
+ return super
+ end
+
+ redef fun is_legal_in(mmodule, anchor)
+ do
+ var mtype
+ if need_anchor then
+ assert anchor != null
+ mtype = anchor_to(mmodule, anchor)
+ else
+ mtype = self
+ end
+ if not mtype.is_ok then return false
+ return mtype.is_subtype(mmodule, null, mtype.mclass.intro.bound_mtype)
+ end
redef fun depth
do
redef fun model do return self.mproperty.intro_mclassdef.mmodule.model
- redef fun lookup_bound(mmodule: MModule, resolved_receiver: MType): MType
+ redef fun lookup_bound(mmodule, resolved_receiver)
do
- return lookup_single_definition(mmodule, resolved_receiver).bound or else new MBottomType(model)
+ # There is two possible invalid cases: the vt does not exists in resolved_receiver or the bound is broken
+ if not resolved_receiver.has_mproperty(mmodule, mproperty) then return new MErrorType(model)
+ return lookup_single_definition(mmodule, resolved_receiver).bound or else new MErrorType(model)
end
private fun lookup_single_definition(mmodule: MModule, resolved_receiver: MType): MVirtualTypeDef
var prop = lookup_single_definition(mmodule, resolved_receiver)
var res = prop.bound
- if res == null then return new MBottomType(model)
+ if res == null then return new MErrorType(model)
# Recursively lookup the fixed result
res = res.lookup_fixed(mmodule, resolved_receiver)
do
if not cleanup_virtual then return self
assert can_resolve_for(mtype, anchor, mmodule)
+
+ if mproperty.is_selftype then return mtype
+
# self is a virtual type declared (or inherited) in mtype
# 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
return res
end
end
- abort
+ # Cannot found `self` in `resolved_receiver`
+ return new MErrorType(model)
end
# A PT is fixed when:
return self.mtype.can_resolve_for(mtype, anchor, mmodule)
end
+ redef fun is_ok do return mtype.is_ok
+
+ redef fun is_legal_in(mmodule, anchor) do return mtype.is_legal_in(mmodule, anchor)
+
redef fun lookup_fixed(mmodule, resolved_receiver)
do
var t = mtype.lookup_fixed(mmodule, resolved_receiver)
redef fun c_name do return "null"
redef fun as_nullable do return self
- redef var as_notnull = new MBottomType(model) is lazy
+ redef var as_notnull: MBottomType = new MBottomType(model) is lazy
redef fun need_anchor do return false
redef fun resolve_for(mtype, anchor, mmodule, cleanup_virtual) do return self
redef fun can_resolve_for(mtype, anchor, mmodule) do return true
# The special universal most specific type.
#
# This type is intended to be only used internally for type computation or analysis and should not be exposed to the user.
-# The bottom type can de used to denote things that are absurd, dead, or the absence of knowledge.
+# The bottom type can de used to denote things that are dead (no instance).
#
# Semantically it is the singleton `null.as_notnull`.
+# Is also means that `self.as_nullable == null`.
class MBottomType
super MType
redef var model
redef fun collect_mtypes(mmodule) do return new HashSet[MClassType]
end
+# A special type used as a silent error marker when building types.
+#
+# This type is intended to be only used internally for type operation and should not be exposed to the user.
+# The error type can de used to denote things that are conflicting or inconsistent.
+#
+# Some methods on types can return a `MErrorType` to denote a broken or a conflicting result.
+# Use `is_ok` to check if a type is (or contains) a `MErrorType` .
+class MErrorType
+ super MType
+ redef var model
+ redef fun to_s do return "error"
+ redef fun full_name do return "error"
+ redef fun c_name do return "error"
+ redef fun need_anchor do return false
+ redef fun resolve_for(mtype, anchor, mmodule, cleanup_virtual) do return self
+ redef fun can_resolve_for(mtype, anchor, mmodule) do return true
+ redef fun is_ok do return false
+
+ redef fun collect_mclassdefs(mmodule) do return new HashSet[MClassDef]
+
+ redef fun collect_mclasses(mmodule) do return new HashSet[MClass]
+
+ redef fun collect_mtypes(mmodule) do return new HashSet[MClassType]
+end
+
# A signature of a method
class MSignature
super MType
#print "select prop {mproperty} for {mtype} in {self}"
# First, select all candidates
var candidates = new Array[MPROPDEF]
- for mpropdef in self.mpropdefs do
- # If the definition is not imported by the module, then skip
- if not mmodule.in_importation <= mpropdef.mclassdef.mmodule then continue
- # If the definition is not inherited by the type, then skip
- if not mtype.is_subtype(mmodule, null, mpropdef.mclassdef.bound_mtype) then continue
- # Else, we keep it
- candidates.add(mpropdef)
+
+ # Here we have two strategies: iterate propdefs or iterate classdefs.
+ var mpropdefs = self.mpropdefs
+ if mpropdefs.length <= 1 or mpropdefs.length < mtype.collect_mclassdefs(mmodule).length then
+ # Iterate on all definitions of `self`, keep only those inherited by `mtype` in `mmodule`
+ for mpropdef in mpropdefs do
+ # If the definition is not imported by the module, then skip
+ if not mmodule.in_importation <= mpropdef.mclassdef.mmodule then continue
+ # If the definition is not inherited by the type, then skip
+ if not mtype.is_subtype(mmodule, null, mpropdef.mclassdef.bound_mtype) then continue
+ # Else, we keep it
+ candidates.add(mpropdef)
+ end
+ else
+ # Iterate on all super-classdefs of `mtype`, keep only the definitions of `self`, if any.
+ for mclassdef in mtype.collect_mclassdefs(mmodule) do
+ var p = mclassdef.mpropdefs_by_property.get_or_null(self)
+ if p != null then candidates.add p
+ end
end
+
# Fast track for only one candidate
if candidates.length <= 1 then
self.lookup_definitions_cache[mmodule, mtype] = candidates
# The formal type associated to the virtual type property
var mvirtualtype = new MVirtualType(self)
+
+ # Is `self` the special virtual type `SELF`?
+ var is_selftype: Bool is lazy do return name == "SELF"
end
# A definition of a property (local property)
nitlanguage / nit.git / blobdiff