1 # This file is part of NIT ( http://www.nitlanguage.org ).
3 # Copyright 2012 Jean Privat <jean@pryen.org>
5 # Licensed under the Apache License, Version 2.0 (the "License");
6 # you may not use this file except in compliance with the License.
7 # You may obtain a copy of the License at
9 # http://www.apache.org/licenses/LICENSE-2.0
11 # Unless required by applicable law or agreed to in writing, software
12 # distributed under the License is distributed on an "AS IS" BASIS,
13 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 # See the License for the specific language governing permissions and
15 # limitations under the License.
17 # Classes, types and properties
19 # All three concepts are defined in this same module because these are strongly connected:
20 # * types are based on classes
21 # * classes contains properties
22 # * some properties are types (virtual types)
24 # TODO: liearization, extern stuff
25 # FIXME: better handling of the types
33 private import more_collections
37 var mclasses
: Array[MClass] = new Array[MClass]
39 # All known properties
40 var mproperties
: Array[MProperty] = new Array[MProperty]
42 # Hierarchy of class definition.
44 # Each classdef is associated with its super-classdefs in regard to
45 # its module of definition.
46 var mclassdef_hierarchy
: POSet[MClassDef] = new POSet[MClassDef]
48 # Class-type hierarchy restricted to the introduction.
50 # The idea is that what is true on introduction is always true whatever
51 # the module considered.
52 # Therefore, this hierarchy is used for a fast positive subtype check.
54 # This poset will evolve in a monotonous way:
55 # * Two non connected nodes will remain unconnected
56 # * New nodes can appear with new edges
57 private var intro_mtype_specialization_hierarchy
: POSet[MClassType] = new POSet[MClassType]
59 # Global overlapped class-type hierarchy.
60 # The hierarchy when all modules are combined.
61 # Therefore, this hierarchy is used for a fast negative subtype check.
63 # This poset will evolve in an anarchic way. Loops can even be created.
65 # FIXME decide what to do on loops
66 private var full_mtype_specialization_hierarchy
: POSet[MClassType] = new POSet[MClassType]
68 # Collections of classes grouped by their short name
69 private var mclasses_by_name
: MultiHashMap[String, MClass] = new MultiHashMap[String, MClass]
71 # Return all class named `name`.
73 # If such a class does not exist, null is returned
74 # (instead of an empty array)
76 # Visibility or modules are not considered
77 fun get_mclasses_by_name
(name
: String): nullable Array[MClass]
79 if mclasses_by_name
.has_key
(name
) then
80 return mclasses_by_name
[name
]
86 # Collections of properties grouped by their short name
87 private var mproperties_by_name
: MultiHashMap[String, MProperty] = new MultiHashMap[String, MProperty]
89 # Return all properties named `name`.
91 # If such a property does not exist, null is returned
92 # (instead of an empty array)
94 # Visibility or modules are not considered
95 fun get_mproperties_by_name
(name
: String): nullable Array[MProperty]
97 if not mproperties_by_name
.has_key
(name
) then
100 return mproperties_by_name
[name
]
105 var null_type
: MNullType = new MNullType(self)
107 # Build an ordered tree with from `concerns`
108 fun concerns_tree
(mconcerns
: Collection[MConcern]): ConcernsTree do
109 var seen
= new HashSet[MConcern]
110 var res
= new ConcernsTree
112 var todo
= new Array[MConcern]
113 todo
.add_all mconcerns
115 while not todo
.is_empty
do
117 if seen
.has
(c
) then continue
118 var pc
= c
.parent_concern
132 # An OrderedTree that can be easily refined for display purposes
134 super OrderedTree[MConcern]
138 # All the classes introduced in the module
139 var intro_mclasses
: Array[MClass] = new Array[MClass]
141 # All the class definitions of the module
142 # (introduction and refinement)
143 var mclassdefs
: Array[MClassDef] = new Array[MClassDef]
145 # Does the current module has a given class `mclass`?
146 # Return true if the mmodule introduces, refines or imports a class.
147 # Visibility is not considered.
148 fun has_mclass
(mclass
: MClass): Bool
150 return self.in_importation
<= mclass
.intro_mmodule
153 # Full hierarchy of introduced ans imported classes.
155 # Create a new hierarchy got by flattening the classes for the module
156 # and its imported modules.
157 # Visibility is not considered.
159 # Note: this function is expensive and is usually used for the main
160 # module of a program only. Do not use it to do you own subtype
162 fun flatten_mclass_hierarchy
: POSet[MClass]
164 var res
= self.flatten_mclass_hierarchy_cache
165 if res
!= null then return res
166 res
= new POSet[MClass]
167 for m
in self.in_importation
.greaters
do
168 for cd
in m
.mclassdefs
do
171 for s
in cd
.supertypes
do
172 res
.add_edge
(c
, s
.mclass
)
176 self.flatten_mclass_hierarchy_cache
= res
180 # Sort a given array of classes using the linerarization order of the module
181 # The most general is first, the most specific is last
182 fun linearize_mclasses
(mclasses
: Array[MClass])
184 self.flatten_mclass_hierarchy
.sort
(mclasses
)
187 # Sort a given array of class definitions using the linerarization order of the module
188 # the refinement link is stronger than the specialisation link
189 # The most general is first, the most specific is last
190 fun linearize_mclassdefs
(mclassdefs
: Array[MClassDef])
192 var sorter
= new MClassDefSorter(self)
193 sorter
.sort
(mclassdefs
)
196 # Sort a given array of property definitions using the linerarization order of the module
197 # the refinement link is stronger than the specialisation link
198 # The most general is first, the most specific is last
199 fun linearize_mpropdefs
(mpropdefs
: Array[MPropDef])
201 var sorter
= new MPropDefSorter(self)
202 sorter
.sort
(mpropdefs
)
205 private var flatten_mclass_hierarchy_cache
: nullable POSet[MClass] = null
207 # The primitive type `Object`, the root of the class hierarchy
208 fun object_type
: MClassType
210 var res
= self.object_type_cache
211 if res
!= null then return res
212 res
= self.get_primitive_class
("Object").mclass_type
213 self.object_type_cache
= res
217 private var object_type_cache
: nullable MClassType
219 # The primitive type `Bool`
220 fun bool_type
: MClassType
222 var res
= self.bool_type_cache
223 if res
!= null then return res
224 res
= self.get_primitive_class
("Bool").mclass_type
225 self.bool_type_cache
= res
229 private var bool_type_cache
: nullable MClassType
231 # The primitive type `Sys`, the main type of the program, if any
232 fun sys_type
: nullable MClassType
234 var clas
= self.model
.get_mclasses_by_name
("Sys")
235 if clas
== null then return null
236 return get_primitive_class
("Sys").mclass_type
239 # Force to get the primitive class named `name` or abort
240 fun get_primitive_class
(name
: String): MClass
242 var cla
= self.model
.get_mclasses_by_name
(name
)
244 if name
== "Bool" then
245 var c
= new MClass(self, name
, 0, enum_kind
, public_visibility
)
246 var cladef
= new MClassDef(self, c
.mclass_type
, new Location(null, 0,0,0,0), new Array[String])
249 print
("Fatal Error: no primitive class {name}")
252 if cla
.length
!= 1 then
253 var msg
= "Fatal Error: more than one primitive class {name}:"
254 for c
in cla
do msg
+= " {c.full_name}"
261 # Try to get the primitive method named `name` on the type `recv`
262 fun try_get_primitive_method
(name
: String, recv
: MClass): nullable MMethod
264 var props
= self.model
.get_mproperties_by_name
(name
)
265 if props
== null then return null
266 var res
: nullable MMethod = null
267 for mprop
in props
do
268 assert mprop
isa MMethod
269 var intro
= mprop
.intro_mclassdef
270 for mclassdef
in recv
.mclassdefs
do
271 if not self.in_importation
.greaters
.has
(mclassdef
.mmodule
) then continue
272 if not mclassdef
.in_hierarchy
.greaters
.has
(intro
) then continue
275 else if res
!= mprop
then
276 print
("Fatal Error: ambigous property name '{name}'; conflict between {mprop.full_name} and {res.full_name}")
285 private class MClassDefSorter
286 super AbstractSorter[MClassDef]
288 redef fun compare
(a
, b
)
292 if ca
!= cb
then return mmodule
.flatten_mclass_hierarchy
.compare
(ca
, cb
)
293 return mmodule
.model
.mclassdef_hierarchy
.compare
(a
, b
)
297 private class MPropDefSorter
298 super AbstractSorter[MPropDef]
300 redef fun compare
(pa
, pb
)
306 if ca
!= cb
then return mmodule
.flatten_mclass_hierarchy
.compare
(ca
, cb
)
307 return mmodule
.model
.mclassdef_hierarchy
.compare
(a
, b
)
313 # `MClass` are global to the model; it means that a `MClass` is not bound to a
314 # specific `MModule`.
316 # This characteristic helps the reasoning about classes in a program since a
317 # single `MClass` object always denote the same class.
319 # The drawback is that classes (`MClass`) contain almost nothing by themselves.
320 # These do not really have properties nor belong to a hierarchy since the property and the
321 # hierarchy of a class depends of the refinement in the modules.
323 # Most services on classes require the precision of a module, and no one can asks what are
324 # the super-classes of a class nor what are properties of a class without precising what is
325 # the module considered.
327 # For instance, during the typing of a source-file, the module considered is the module of the file.
328 # eg. the question *is the method `foo` exists in the class `Bar`?* must be reformulated into
329 # *is the method `foo` exists in the class `Bar` in the current module?*
331 # During some global analysis, the module considered may be the main module of the program.
335 # The module that introduce the class
336 # While classes are not bound to a specific module,
337 # the introducing module is used for naming an visibility
338 var intro_mmodule
: MModule
340 # The short name of the class
341 # In Nit, the name of a class cannot evolve in refinements
342 redef var name
: String
344 # The canonical name of the class
345 # Example: `"owner::module::MyClass"`
346 fun full_name
: String
348 return "{self.intro_mmodule.full_name}::{name}"
351 # The number of generic formal parameters
352 # 0 if the class is not generic
355 # The kind of the class (interface, abstract class, etc.)
356 # In Nit, the kind of a class cannot evolve in refinements
359 # The visibility of the class
360 # In Nit, the visibility of a class cannot evolve in refinements
361 var visibility
: MVisibility
363 init(intro_mmodule
: MModule, name
: String, arity
: Int, kind
: MClassKind, visibility
: MVisibility)
365 self.intro_mmodule
= intro_mmodule
369 self.visibility
= visibility
370 intro_mmodule
.intro_mclasses
.add
(self)
371 var model
= intro_mmodule
.model
372 model
.mclasses_by_name
.add_one
(name
, self)
373 model
.mclasses
.add
(self)
375 # Create the formal parameter types
377 var mparametertypes
= new Array[MParameterType]
378 for i
in [0..arity
[ do
379 var mparametertype
= new MParameterType(self, i
)
380 mparametertypes
.add
(mparametertype
)
382 var mclass_type
= new MGenericType(self, mparametertypes
)
383 self.mclass_type
= mclass_type
384 self.get_mtype_cache
.add
(mclass_type
)
386 self.mclass_type
= new MClassType(self)
390 redef fun model
do return intro_mmodule
.model
392 # All class definitions (introduction and refinements)
393 var mclassdefs
: Array[MClassDef] = new Array[MClassDef]
396 redef fun to_s
do return self.name
398 # The definition that introduced the class
399 # Warning: the introduction is the first `MClassDef` object associated
400 # to self. If self is just created without having any associated
401 # definition, this method will abort
404 assert has_a_first_definition
: not mclassdefs
.is_empty
405 return mclassdefs
.first
408 # Return the class `self` in the class hierarchy of the module `mmodule`.
410 # SEE: `MModule::flatten_mclass_hierarchy`
411 # REQUIRE: `mmodule.has_mclass(self)`
412 fun in_hierarchy
(mmodule
: MModule): POSetElement[MClass]
414 return mmodule
.flatten_mclass_hierarchy
[self]
417 # The principal static type of the class.
419 # For non-generic class, mclass_type is the only `MClassType` based
422 # For a generic class, the arguments are the formal parameters.
423 # i.e.: for the class Array[E:Object], the `mclass_type` is Array[E].
424 # If you want Array[Object] the see `MClassDef::bound_mtype`
426 # For generic classes, the mclass_type is also the way to get a formal
427 # generic parameter type.
429 # To get other types based on a generic class, see `get_mtype`.
431 # ENSURE: `mclass_type.mclass == self`
432 var mclass_type
: MClassType
434 # Return a generic type based on the class
435 # Is the class is not generic, then the result is `mclass_type`
437 # REQUIRE: `mtype_arguments.length == self.arity`
438 fun get_mtype
(mtype_arguments
: Array[MType]): MClassType
440 assert mtype_arguments
.length
== self.arity
441 if self.arity
== 0 then return self.mclass_type
442 for t
in self.get_mtype_cache
do
443 if t
.arguments
== mtype_arguments
then
447 var res
= new MGenericType(self, mtype_arguments
)
448 self.get_mtype_cache
.add res
452 private var get_mtype_cache
: Array[MGenericType] = new Array[MGenericType]
456 # A definition (an introduction or a refinement) of a class in a module
458 # A `MClassDef` is associated with an explicit (or almost) definition of a
459 # class. Unlike `MClass`, a `MClassDef` is a local definition that belong to
460 # a specific class and a specific module, and contains declarations like super-classes
463 # It is the class definitions that are the backbone of most things in the model:
464 # ClassDefs are defined with regard with other classdefs.
465 # Refinement and specialization are combined to produce a big poset called the `Model::mclassdef_hierarchy`.
467 # Moreover, the extension and the intention of types is defined by looking at the MClassDefs.
471 # The module where the definition is
474 # The associated `MClass`
477 # The bounded type associated to the mclassdef
479 # For a non-generic class, `bound_mtype` and `mclass.mclass_type`
483 # For the classdef Array[E: Object], the bound_mtype is Array[Object].
484 # If you want Array[E], then see `mclass.mclass_type`
486 # ENSURE: `bound_mtype.mclass == self.mclass`
487 var bound_mtype
: MClassType
489 # Name of each formal generic parameter (in order of declaration)
490 var parameter_names
: Array[String]
492 # The origin of the definition
493 var location
: Location
495 # Internal name combining the module and the class
496 # Example: "mymodule#MyClass"
497 redef var to_s
: String
499 init(mmodule
: MModule, bound_mtype
: MClassType, location
: Location, parameter_names
: Array[String])
501 assert bound_mtype
.mclass
.arity
== parameter_names
.length
502 self.bound_mtype
= bound_mtype
503 self.mmodule
= mmodule
504 self.mclass
= bound_mtype
.mclass
505 self.location
= location
506 mmodule
.mclassdefs
.add
(self)
507 mclass
.mclassdefs
.add
(self)
508 self.parameter_names
= parameter_names
509 self.to_s
= "{mmodule}#{mclass}"
512 # Actually the name of the `mclass`
513 redef fun name
do return mclass
.name
515 redef fun model
do return mmodule
.model
517 # All declared super-types
518 # FIXME: quite ugly but not better idea yet
519 var supertypes
: Array[MClassType] = new Array[MClassType]
521 # Register some super-types for the class (ie "super SomeType")
523 # The hierarchy must not already be set
524 # REQUIRE: `self.in_hierarchy == null`
525 fun set_supertypes
(supertypes
: Array[MClassType])
527 assert unique_invocation
: self.in_hierarchy
== null
528 var mmodule
= self.mmodule
529 var model
= mmodule
.model
530 var mtype
= self.bound_mtype
532 for supertype
in supertypes
do
533 self.supertypes
.add
(supertype
)
535 # Register in full_type_specialization_hierarchy
536 model
.full_mtype_specialization_hierarchy
.add_edge
(mtype
, supertype
)
537 # Register in intro_type_specialization_hierarchy
538 if mclass
.intro_mmodule
== mmodule
and supertype
.mclass
.intro_mmodule
== mmodule
then
539 model
.intro_mtype_specialization_hierarchy
.add_edge
(mtype
, supertype
)
545 # Collect the super-types (set by set_supertypes) to build the hierarchy
547 # This function can only invoked once by class
548 # REQUIRE: `self.in_hierarchy == null`
549 # ENSURE: `self.in_hierarchy != null`
552 assert unique_invocation
: self.in_hierarchy
== null
553 var model
= mmodule
.model
554 var res
= model
.mclassdef_hierarchy
.add_node
(self)
555 self.in_hierarchy
= res
556 var mtype
= self.bound_mtype
558 # Here we need to connect the mclassdef to its pairs in the mclassdef_hierarchy
559 # The simpliest way is to attach it to collect_mclassdefs
560 for mclassdef
in mtype
.collect_mclassdefs
(mmodule
) do
561 res
.poset
.add_edge
(self, mclassdef
)
565 # The view of the class definition in `mclassdef_hierarchy`
566 var in_hierarchy
: nullable POSetElement[MClassDef] = null
568 # Is the definition the one that introduced `mclass`?
569 fun is_intro
: Bool do return mclass
.intro
== self
571 # All properties introduced by the classdef
572 var intro_mproperties
: Array[MProperty] = new Array[MProperty]
574 # All property definitions in the class (introductions and redefinitions)
575 var mpropdefs
: Array[MPropDef] = new Array[MPropDef]
578 # A global static type
580 # MType are global to the model; it means that a `MType` is not bound to a
581 # specific `MModule`.
582 # This characteristic helps the reasoning about static types in a program
583 # since a single `MType` object always denote the same type.
585 # However, because a `MType` is global, it does not really have properties
586 # nor have subtypes to a hierarchy since the property and the class hierarchy
587 # depends of a module.
588 # Moreover, virtual types an formal generic parameter types also depends on
589 # a receiver to have sense.
591 # Therefore, most method of the types require a module and an anchor.
592 # The module is used to know what are the classes and the specialization
594 # The anchor is used to know what is the bound of the virtual types and formal
595 # generic parameter types.
597 # MType are not directly usable to get properties. See the `anchor_to` method
598 # and the `MClassType` class.
600 # FIXME: the order of the parameters is not the best. We mus pick on from:
601 # * foo(mmodule, anchor, othertype)
602 # * foo(othertype, anchor, mmodule)
603 # * foo(anchor, mmodule, othertype)
604 # * foo(othertype, mmodule, anchor)
608 redef fun name
do return to_s
610 # Return true if `self` is an subtype of `sup`.
611 # The typing is done using the standard typing policy of Nit.
613 # REQUIRE: `anchor == null implies not self.need_anchor and not sup.need_anchor`
614 # REQUIRE: `anchor != null implies self.can_resolve_for(anchor, null, mmodule) and sup.can_resolve_for(anchor, null, mmodule)`
615 fun is_subtype
(mmodule
: MModule, anchor
: nullable MClassType, sup
: MType): Bool
618 if sub
== sup
then return true
619 if anchor
== null then
620 assert not sub
.need_anchor
621 assert not sup
.need_anchor
623 assert sub
.can_resolve_for
(anchor
, null, mmodule
)
624 assert sup
.can_resolve_for
(anchor
, null, mmodule
)
627 # First, resolve the formal types to a common version in the receiver
628 # The trick here is that fixed formal type will be associed to the bound
629 # And unfixed formal types will be associed to a canonical formal type.
630 if sub
isa MParameterType or sub
isa MVirtualType then
631 assert anchor
!= null
632 sub
= sub
.resolve_for
(anchor
.mclass
.mclass_type
, anchor
, mmodule
, false)
634 if sup
isa MParameterType or sup
isa MVirtualType then
635 assert anchor
!= null
636 sup
= sup
.resolve_for
(anchor
.mclass
.mclass_type
, anchor
, mmodule
, false)
639 # Does `sup` accept null or not?
640 # Discard the nullable marker if it exists
641 var sup_accept_null
= false
642 if sup
isa MNullableType then
643 sup_accept_null
= true
645 else if sup
isa MNullType then
646 sup_accept_null
= true
649 # Can `sub` provide null or not?
650 # Thus we can match with `sup_accept_null`
651 # Also discard the nullable marker if it exists
652 if sub
isa MNullableType then
653 if not sup_accept_null
then return false
655 else if sub
isa MNullType then
656 return sup_accept_null
658 # Now the case of direct null and nullable is over.
660 # A unfixed formal type can only accept itself
661 if sup
isa MParameterType or sup
isa MVirtualType then
665 # If `sub` is a formal type, then it is accepted if its bound is accepted
666 if sub
isa MParameterType or sub
isa MVirtualType then
667 assert anchor
!= null
668 sub
= sub
.anchor_to
(mmodule
, anchor
)
670 # Manage the second layer of null/nullable
671 if sub
isa MNullableType then
672 if not sup_accept_null
then return false
674 else if sub
isa MNullType then
675 return sup_accept_null
679 assert sub
isa MClassType # It is the only remaining type
681 if sup
isa MNullType then
682 # `sup` accepts only null
686 assert sup
isa MClassType # It is the only remaining type
688 # Now both are MClassType, we need to dig
690 if sub
== sup
then return true
692 if anchor
== null then anchor
= sub
# UGLY: any anchor will work
693 var resolved_sub
= sub
.anchor_to
(mmodule
, anchor
)
694 var res
= resolved_sub
.collect_mclasses
(mmodule
).has
(sup
.mclass
)
695 if res
== false then return false
696 if not sup
isa MGenericType then return true
697 var sub2
= sub
.supertype_to
(mmodule
, anchor
, sup
.mclass
)
698 assert sub2
.mclass
== sup
.mclass
699 for i
in [0..sup
.mclass
.arity
[ do
700 var sub_arg
= sub2
.arguments
[i
]
701 var sup_arg
= sup
.arguments
[i
]
702 res
= sub_arg
.is_subtype
(mmodule
, anchor
, sup_arg
)
703 if res
== false then return false
708 # The base class type on which self is based
710 # This base type is used to get property (an internally to perform
711 # unsafe type comparison).
713 # Beware: some types (like null) are not based on a class thus this
716 # Basically, this function transform the virtual types and parameter
717 # types to their bounds.
721 # class B super A end
723 # class Y super X end
731 # Map[T,U] anchor_to H #-> Map[B,Y]
733 # Explanation of the example:
734 # In H, T is set to B, because "H super G[B]", and U is bound to Y,
735 # because "redef type U: Y". Therefore, Map[T, U] is bound to
738 # ENSURE: `not self.need_anchor implies result == self`
739 # ENSURE: `not result.need_anchor`
740 fun anchor_to
(mmodule
: MModule, anchor
: MClassType): MType
742 if not need_anchor
then return self
743 assert not anchor
.need_anchor
744 # Just resolve to the anchor and clear all the virtual types
745 var res
= self.resolve_for
(anchor
, null, mmodule
, true)
746 assert not res
.need_anchor
750 # Does `self` contain a virtual type or a formal generic parameter type?
751 # In order to remove those types, you usually want to use `anchor_to`.
752 fun need_anchor
: Bool do return true
754 # Return the supertype when adapted to a class.
756 # In Nit, for each super-class of a type, there is a equivalent super-type.
760 # class H[V] super G[V, Bool] end
761 # H[Int] supertype_to G #-> G[Int, Bool]
763 # REQUIRE: `super_mclass` is a super-class of `self`
764 # REQUIRE: `self.need_anchor implies anchor != null and self.can_resolve_for(anchor, null, mmodule)`
765 # ENSURE: `result.mclass = super_mclass`
766 fun supertype_to
(mmodule
: MModule, anchor
: nullable MClassType, super_mclass
: MClass): MClassType
768 if super_mclass
.arity
== 0 then return super_mclass
.mclass_type
769 if self isa MClassType and self.mclass
== super_mclass
then return self
771 if self.need_anchor
then
772 assert anchor
!= null
773 resolved_self
= self.anchor_to
(mmodule
, anchor
)
777 var supertypes
= resolved_self
.collect_mtypes
(mmodule
)
778 for supertype
in supertypes
do
779 if supertype
.mclass
== super_mclass
then
780 # FIXME: Here, we stop on the first goal. Should we check others and detect inconsistencies?
781 return supertype
.resolve_for
(self, anchor
, mmodule
, false)
787 # Replace formals generic types in self with resolved values in `mtype`
788 # If `cleanup_virtual` is true, then virtual types are also replaced
791 # This function returns self if `need_anchor` is false.
796 # class H[F] super G[F] end
799 # * Array[E].resolve_for(H[Int]) #-> Array[Int]
800 # * Array[E].resolve_for(G[Z], X[Int]) #-> Array[Z]
802 # Explanation of the example:
803 # * Array[E].need_anchor is true because there is a formal generic parameter type E
804 # * E makes sense for H[Int] because E is a formal parameter of G and H specialize G
805 # * Since "H[F] super G[F]", E is in fact F for H
806 # * More specifically, in H[Int], E is Int
807 # * So, in H[Int], Array[E] is Array[Int]
809 # This function is mainly used to inherit a signature.
810 # Because, unlike `anchor_to`, we do not want a full resolution of
811 # a type but only an adapted version of it.
816 # fun foo(e:E):E is abstract
818 # class B super A[Int] end
820 # The signature on foo is (e: E): E
821 # If we resolve the signature for B, we get (e:Int):Int
826 # fun foo(e:E) is abstract
830 # fun bar do a.foo(x) # <- x is here
833 # The first question is: is foo available on `a`?
835 # The static type of a is `A[Array[F]]`, that is an open type.
836 # in order to find a method `foo`, whe must look at a resolved type.
838 # A[Array[F]].anchor_to(B[nullable Object]) #-> A[Array[nullable Object]]
840 # the method `foo` exists in `A[Array[nullable Object]]`, therefore `foo` exists for `a`.
842 # The next question is: what is the accepted types for `x`?
844 # the signature of `foo` is `foo(e:E)`, thus we must resolve the type E
846 # E.resolve_for(A[Array[F]],B[nullable Object]) #-> Array[F]
848 # The resolution can be done because `E` make sense for the class A (see `can_resolve_for`)
850 # FIXME: the parameter `cleanup_virtual` is just a bad idea, but having
851 # two function instead of one seems also to be a bad idea.
853 # REQUIRE: `can_resolve_for(mtype, anchor, mmodule)`
854 # ENSURE: `not self.need_anchor implies result == self`
855 fun resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule, cleanup_virtual
: Bool): MType is abstract
857 # Can the type be resolved?
859 # In order to resolve open types, the formal types must make sence.
868 # * E.can_resolve_for(A[Int]) #-> true, E make sense in A
869 # * E.can_resolve_for(B[Int]) #-> false, E does not make sense in B
870 # * B[E].can_resolve_for(A[F], B[Object]) #-> true,
871 # B[E] is a red hearing only the E is important,
874 # REQUIRE: `anchor != null implies not anchor.need_anchor`
875 # REQUIRE: `mtype.need_anchor implies anchor != null and mtype.can_resolve_for(anchor, null, mmodule)`
876 # ENSURE: `not self.need_anchor implies result == true`
877 fun can_resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule): Bool is abstract
879 # Return the nullable version of the type
880 # If the type is already nullable then self is returned
881 fun as_nullable
: MType
883 var res
= self.as_nullable_cache
884 if res
!= null then return res
885 res
= new MNullableType(self)
886 self.as_nullable_cache
= res
890 # Return the not nullable version of the type
891 # Is the type is already not nullable, then self is returned.
893 # Note: this just remove the `nullable` notation, but the result can still contains null.
894 # For instance if `self isa MNullType` or self is a a formal type bounded by a nullable type.
895 fun as_notnullable
: MType
900 private var as_nullable_cache
: nullable MType = null
903 # The deph of the type seen as a tree.
910 # Formal types have a depth of 1.
916 # The length of the type seen as a tree.
923 # Formal types have a length of 1.
929 # Compute all the classdefs inherited/imported.
930 # The returned set contains:
931 # * the class definitions from `mmodule` and its imported modules
932 # * the class definitions of this type and its super-types
934 # This function is used mainly internally.
936 # REQUIRE: `not self.need_anchor`
937 fun collect_mclassdefs
(mmodule
: MModule): Set[MClassDef] is abstract
939 # Compute all the super-classes.
940 # This function is used mainly internally.
942 # REQUIRE: `not self.need_anchor`
943 fun collect_mclasses
(mmodule
: MModule): Set[MClass] is abstract
945 # Compute all the declared super-types.
946 # Super-types are returned as declared in the classdefs (verbatim).
947 # This function is used mainly internally.
949 # REQUIRE: `not self.need_anchor`
950 fun collect_mtypes
(mmodule
: MModule): Set[MClassType] is abstract
952 # Is the property in self for a given module
953 # This method does not filter visibility or whatever
955 # REQUIRE: `not self.need_anchor`
956 fun has_mproperty
(mmodule
: MModule, mproperty
: MProperty): Bool
958 assert not self.need_anchor
959 return self.collect_mclassdefs
(mmodule
).has
(mproperty
.intro_mclassdef
)
963 # A type based on a class.
965 # `MClassType` have properties (see `has_mproperty`).
969 # The associated class
972 redef fun model
do return self.mclass
.intro_mmodule
.model
974 private init(mclass
: MClass)
979 # The formal arguments of the type
980 # ENSURE: `result.length == self.mclass.arity`
981 var arguments
: Array[MType] = new Array[MType]
983 redef fun to_s
do return mclass
.to_s
985 redef fun need_anchor
do return false
987 redef fun anchor_to
(mmodule
: MModule, anchor
: MClassType): MClassType
989 return super.as(MClassType)
992 redef fun resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule, cleanup_virtual
: Bool): MClassType do return self
994 redef fun can_resolve_for
(mtype
, anchor
, mmodule
) do return true
996 redef fun collect_mclassdefs
(mmodule
)
998 assert not self.need_anchor
999 var cache
= self.collect_mclassdefs_cache
1000 if not cache
.has_key
(mmodule
) then
1001 self.collect_things
(mmodule
)
1003 return cache
[mmodule
]
1006 redef fun collect_mclasses
(mmodule
)
1008 assert not self.need_anchor
1009 var cache
= self.collect_mclasses_cache
1010 if not cache
.has_key
(mmodule
) then
1011 self.collect_things
(mmodule
)
1013 return cache
[mmodule
]
1016 redef fun collect_mtypes
(mmodule
)
1018 assert not self.need_anchor
1019 var cache
= self.collect_mtypes_cache
1020 if not cache
.has_key
(mmodule
) then
1021 self.collect_things
(mmodule
)
1023 return cache
[mmodule
]
1026 # common implementation for `collect_mclassdefs`, `collect_mclasses`, and `collect_mtypes`.
1027 private fun collect_things
(mmodule
: MModule)
1029 var res
= new HashSet[MClassDef]
1030 var seen
= new HashSet[MClass]
1031 var types
= new HashSet[MClassType]
1032 seen
.add
(self.mclass
)
1033 var todo
= [self.mclass
]
1034 while not todo
.is_empty
do
1035 var mclass
= todo
.pop
1036 #print "process {mclass}"
1037 for mclassdef
in mclass
.mclassdefs
do
1038 if not mmodule
.in_importation
<= mclassdef
.mmodule
then continue
1039 #print " process {mclassdef}"
1041 for supertype
in mclassdef
.supertypes
do
1042 types
.add
(supertype
)
1043 var superclass
= supertype
.mclass
1044 if seen
.has
(superclass
) then continue
1045 #print " add {superclass}"
1046 seen
.add
(superclass
)
1047 todo
.add
(superclass
)
1051 collect_mclassdefs_cache
[mmodule
] = res
1052 collect_mclasses_cache
[mmodule
] = seen
1053 collect_mtypes_cache
[mmodule
] = types
1056 private var collect_mclassdefs_cache
: HashMap[MModule, Set[MClassDef]] = new HashMap[MModule, Set[MClassDef]]
1057 private var collect_mclasses_cache
: HashMap[MModule, Set[MClass]] = new HashMap[MModule, Set[MClass]]
1058 private var collect_mtypes_cache
: HashMap[MModule, Set[MClassType]] = new HashMap[MModule, Set[MClassType]]
1062 # A type based on a generic class.
1063 # A generic type a just a class with additional formal generic arguments.
1067 private init(mclass
: MClass, arguments
: Array[MType])
1070 assert self.mclass
.arity
== arguments
.length
1071 self.arguments
= arguments
1073 self.need_anchor
= false
1074 for t
in arguments
do
1075 if t
.need_anchor
then
1076 self.need_anchor
= true
1081 self.to_s
= "{mclass}[{arguments.join(", ")}]"
1084 # Recursively print the type of the arguments within brackets.
1085 # Example: `"Map[String, List[Int]]"`
1086 redef var to_s
: String
1088 redef var need_anchor
: Bool
1090 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1092 if not need_anchor
then return self
1093 assert can_resolve_for
(mtype
, anchor
, mmodule
)
1094 var types
= new Array[MType]
1095 for t
in arguments
do
1096 types
.add
(t
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
))
1098 return mclass
.get_mtype
(types
)
1101 redef fun can_resolve_for
(mtype
, anchor
, mmodule
)
1103 if not need_anchor
then return true
1104 for t
in arguments
do
1105 if not t
.can_resolve_for
(mtype
, anchor
, mmodule
) then return false
1114 for a
in self.arguments
do
1116 if d
> dmax
then dmax
= d
1124 for a
in self.arguments
do
1131 # A virtual formal type.
1135 # The property associated with the type.
1136 # Its the definitions of this property that determine the bound or the virtual type.
1137 var mproperty
: MProperty
1139 redef fun model
do return self.mproperty
.intro_mclassdef
.mmodule
.model
1141 # Lookup the bound for a given resolved_receiver
1142 # The result may be a other virtual type (or a parameter type)
1144 # The result is returned exactly as declared in the "type" property (verbatim).
1146 # In case of conflict, the method aborts.
1147 fun lookup_bound
(mmodule
: MModule, resolved_receiver
: MType): MType
1149 assert not resolved_receiver
.need_anchor
1150 var props
= self.mproperty
.lookup_definitions
(mmodule
, resolved_receiver
)
1151 if props
.is_empty
then
1153 else if props
.length
== 1 then
1154 return props
.first
.as(MVirtualTypeDef).bound
.as(not null)
1156 var types
= new ArraySet[MType]
1158 types
.add
(p
.as(MVirtualTypeDef).bound
.as(not null))
1160 if types
.length
== 1 then
1166 # Is the virtual type fixed for a given resolved_receiver?
1167 fun is_fixed
(mmodule
: MModule, resolved_receiver
: MType): Bool
1169 assert not resolved_receiver
.need_anchor
1170 var props
= self.mproperty
.lookup_definitions
(mmodule
, resolved_receiver
)
1171 if props
.is_empty
then
1175 if p
.as(MVirtualTypeDef).is_fixed
then return true
1180 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1182 assert can_resolve_for
(mtype
, anchor
, mmodule
)
1183 # self is a virtual type declared (or inherited) in mtype
1184 # The point of the function it to get the bound of the virtual type that make sense for mtype
1185 # But because mtype is maybe a virtual/formal type, we need to get a real receiver first
1186 #print "{class_name}: {self}/{mtype}/{anchor}?"
1187 var resolved_reciever
1188 if mtype
.need_anchor
then
1189 assert anchor
!= null
1190 resolved_reciever
= mtype
.resolve_for
(anchor
, null, mmodule
, true)
1192 resolved_reciever
= mtype
1194 # Now, we can get the bound
1195 var verbatim_bound
= lookup_bound
(mmodule
, resolved_reciever
)
1196 # The bound is exactly as declared in the "type" property, so we must resolve it again
1197 var res
= verbatim_bound
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1198 #print "{class_name}: {self}/{mtype}/{anchor} -> {self}/{resolved_reciever}/{anchor} -> {verbatim_bound}/{mtype}/{anchor} -> {res}"
1200 # What to return here? There is a bunch a special cases:
1201 # If 'cleanup_virtual' we must return the resolved type, since we cannot return self
1202 if cleanup_virtual
then return res
1203 # If the reciever is a intern class, then the virtual type cannot be redefined since there is no possible subclass. self is just fixed. so simply return the resolution
1204 if resolved_reciever
isa MNullableType then resolved_reciever
= resolved_reciever
.mtype
1205 if resolved_reciever
.as(MClassType).mclass
.kind
== enum_kind
then return res
1206 # If the resolved type isa MVirtualType, it means that self was bound to it, and cannot be unbound. self is just fixed. so return the resolution.
1207 if res
isa MVirtualType then return res
1208 # If we are final, just return the resolution
1209 if is_fixed
(mmodule
, resolved_reciever
) then return res
1210 # It the resolved type isa intern class, then there is no possible valid redefinition is any potentiel subclass. self is just fixed. so simply return the resolution
1211 if res
isa MClassType and res
.mclass
.kind
== enum_kind
then return res
1212 # TODO: Add 'fixed' virtual type in the specification.
1213 # TODO: What if bound to a MParameterType?
1214 # Note that Nullable types can always be redefined by the non nullable version, so there is no specific case on it.
1216 # If anything apply, then `self' cannot be resolved, so return self
1220 redef fun can_resolve_for
(mtype
, anchor
, mmodule
)
1222 if mtype
.need_anchor
then
1223 assert anchor
!= null
1224 mtype
= mtype
.anchor_to
(mmodule
, anchor
)
1226 return mtype
.has_mproperty
(mmodule
, mproperty
)
1229 redef fun to_s
do return self.mproperty
.to_s
1231 init(mproperty
: MProperty)
1233 self.mproperty
= mproperty
1237 # The type associated the a formal parameter generic type of a class
1239 # Each parameter type is associated to a specific class.
1240 # It's mean that all refinements of a same class "share" the parameter type,
1241 # but that a generic subclass has its on parameter types.
1243 # However, in the sense of the meta-model, a parameter type of a class is
1244 # a valid type in a subclass. The "in the sense of the meta-model" is
1245 # important because, in the Nit language, the programmer cannot refers
1246 # directly to the parameter types of the super-classes.
1250 # fun e: E is abstract
1255 # In the class definition B[F], `F` is a valid type but `E` is not.
1256 # However, `self.e` is a valid method call, and the signature of `e` is
1259 # Note that parameter types are shared among class refinements.
1260 # Therefore parameter only have an internal name (see `to_s` for details).
1261 # TODO: Add a `name_for` to get better messages.
1262 class MParameterType
1265 # The generic class where the parameter belong
1268 redef fun model
do return self.mclass
.intro_mmodule
.model
1270 # The position of the parameter (0 for the first parameter)
1271 # FIXME: is `position` a better name?
1274 # Internal name of the parameter type
1275 # Names of parameter types changes in each class definition
1276 # Therefore, this method return an internal name.
1277 # Example: return "G#1" for the second parameter of the class G
1278 # FIXME: add a way to get the real name in a classdef
1279 redef fun to_s
do return "{mclass}#{rank}"
1281 # Resolve the bound for a given resolved_receiver
1282 # The result may be a other virtual type (or a parameter type)
1283 fun lookup_bound
(mmodule
: MModule, resolved_receiver
: MType): MType
1285 assert not resolved_receiver
.need_anchor
1286 var goalclass
= self.mclass
1287 var supertypes
= resolved_receiver
.collect_mtypes
(mmodule
)
1288 for t
in supertypes
do
1289 if t
.mclass
== goalclass
then
1290 # Yeah! c specialize goalclass with a "super `t'". So the question is what is the argument of f
1291 # FIXME: Here, we stop on the first goal. Should we check others and detect inconsistencies?
1292 var res
= t
.arguments
[self.rank
]
1299 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1301 assert can_resolve_for
(mtype
, anchor
, mmodule
)
1302 #print "{class_name}: {self}/{mtype}/{anchor}?"
1304 if mtype
isa MGenericType and mtype
.mclass
== self.mclass
then
1305 return mtype
.arguments
[self.rank
]
1308 # self is a parameter type of mtype (or of a super-class of mtype)
1309 # The point of the function it to get the bound of the virtual type that make sense for mtype
1310 # But because mtype is maybe a virtual/formal type, we need to get a real receiver first
1311 # FIXME: What happend here is far from clear. Thus this part must be validated and clarified
1312 var resolved_receiver
1313 if mtype
.need_anchor
then
1314 assert anchor
!= null
1315 resolved_receiver
= mtype
.resolve_for
(anchor
.mclass
.mclass_type
, anchor
, mmodule
, true)
1317 resolved_receiver
= mtype
1319 if resolved_receiver
isa MNullableType then resolved_receiver
= resolved_receiver
.mtype
1320 if resolved_receiver
isa MParameterType then
1321 assert resolved_receiver
.mclass
== anchor
.mclass
1322 resolved_receiver
= anchor
.arguments
[resolved_receiver
.rank
]
1323 if resolved_receiver
isa MNullableType then resolved_receiver
= resolved_receiver
.mtype
1325 assert resolved_receiver
isa MClassType
1327 # Eh! The parameter is in the current class.
1328 # So we return the corresponding argument, no mater what!
1329 if resolved_receiver
.mclass
== self.mclass
then
1330 var res
= resolved_receiver
.arguments
[self.rank
]
1331 #print "{class_name}: {self}/{mtype}/{anchor} -> direct {res}"
1335 if resolved_receiver
.need_anchor
then
1336 assert anchor
!= null
1337 resolved_receiver
= resolved_receiver
.resolve_for
(anchor
, null, mmodule
, false)
1339 # Now, we can get the bound
1340 var verbatim_bound
= lookup_bound
(mmodule
, resolved_receiver
)
1341 # The bound is exactly as declared in the "type" property, so we must resolve it again
1342 var res
= verbatim_bound
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1344 #print "{class_name}: {self}/{mtype}/{anchor} -> indirect {res}"
1349 redef fun can_resolve_for
(mtype
, anchor
, mmodule
)
1351 if mtype
.need_anchor
then
1352 assert anchor
!= null
1353 mtype
= mtype
.anchor_to
(mmodule
, anchor
)
1355 return mtype
.collect_mclassdefs
(mmodule
).has
(mclass
.intro
)
1358 init(mclass
: MClass, rank
: Int)
1360 self.mclass
= mclass
1365 # A type prefixed with "nullable"
1369 # The base type of the nullable type
1372 redef fun model
do return self.mtype
.model
1377 self.to_s
= "nullable {mtype}"
1380 redef var to_s
: String
1382 redef fun need_anchor
do return mtype
.need_anchor
1383 redef fun as_nullable
do return self
1384 redef fun as_notnullable
do return mtype
1385 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1387 var res
= self.mtype
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1388 return res
.as_nullable
1391 redef fun can_resolve_for
(mtype
, anchor
, mmodule
)
1393 return self.mtype
.can_resolve_for
(mtype
, anchor
, mmodule
)
1396 redef fun depth
do return self.mtype
.depth
1398 redef fun length
do return self.mtype
.length
1400 redef fun collect_mclassdefs
(mmodule
)
1402 assert not self.need_anchor
1403 return self.mtype
.collect_mclassdefs
(mmodule
)
1406 redef fun collect_mclasses
(mmodule
)
1408 assert not self.need_anchor
1409 return self.mtype
.collect_mclasses
(mmodule
)
1412 redef fun collect_mtypes
(mmodule
)
1414 assert not self.need_anchor
1415 return self.mtype
.collect_mtypes
(mmodule
)
1419 # The type of the only value null
1421 # The is only one null type per model, see `MModel::null_type`.
1424 redef var model
: Model
1425 protected init(model
: Model)
1429 redef fun to_s
do return "null"
1430 redef fun as_nullable
do return self
1431 redef fun need_anchor
do return false
1432 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
) do return self
1433 redef fun can_resolve_for
(mtype
, anchor
, mmodule
) do return true
1435 redef fun collect_mclassdefs
(mmodule
) do return new HashSet[MClassDef]
1437 redef fun collect_mclasses
(mmodule
) do return new HashSet[MClass]
1439 redef fun collect_mtypes
(mmodule
) do return new HashSet[MClassType]
1442 # A signature of a method
1446 # The each parameter (in order)
1447 var mparameters
: Array[MParameter]
1449 # The return type (null for a procedure)
1450 var return_mtype
: nullable MType
1455 var t
= self.return_mtype
1456 if t
!= null then dmax
= t
.depth
1457 for p
in mparameters
do
1458 var d
= p
.mtype
.depth
1459 if d
> dmax
then dmax
= d
1467 var t
= self.return_mtype
1468 if t
!= null then res
+= t
.length
1469 for p
in mparameters
do
1470 res
+= p
.mtype
.length
1475 # REQUIRE: 1 <= mparameters.count p -> p.is_vararg
1476 init(mparameters
: Array[MParameter], return_mtype
: nullable MType)
1478 var vararg_rank
= -1
1479 for i
in [0..mparameters
.length
[ do
1480 var parameter
= mparameters
[i
]
1481 if parameter
.is_vararg
then
1482 assert vararg_rank
== -1
1486 self.mparameters
= mparameters
1487 self.return_mtype
= return_mtype
1488 self.vararg_rank
= vararg_rank
1491 # The rank of the ellipsis (`...`) for vararg (starting from 0).
1492 # value is -1 if there is no vararg.
1493 # Example: for "(a: Int, b: Bool..., c: Char)" #-> vararg_rank=1
1494 var vararg_rank
: Int
1496 # The number or parameters
1497 fun arity
: Int do return mparameters
.length
1501 var b
= new FlatBuffer
1502 if not mparameters
.is_empty
then
1504 for i
in [0..mparameters
.length
[ do
1505 var mparameter
= mparameters
[i
]
1506 if i
> 0 then b
.append
(", ")
1507 b
.append
(mparameter
.name
)
1509 b
.append
(mparameter
.mtype
.to_s
)
1510 if mparameter
.is_vararg
then
1516 var ret
= self.return_mtype
1524 redef fun resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule, cleanup_virtual
: Bool): MSignature
1526 var params
= new Array[MParameter]
1527 for p
in self.mparameters
do
1528 params
.add
(p
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
))
1530 var ret
= self.return_mtype
1532 ret
= ret
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1534 var res
= new MSignature(params
, ret
)
1539 # A parameter in a signature
1543 # The name of the parameter
1544 redef var name
: String
1546 # The static type of the parameter
1549 # Is the parameter a vararg?
1552 init(name
: String, mtype
: MType, is_vararg
: Bool) do
1555 self.is_vararg
= is_vararg
1561 return "{name}: {mtype}..."
1563 return "{name}: {mtype}"
1567 fun resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule, cleanup_virtual
: Bool): MParameter
1569 if not self.mtype
.need_anchor
then return self
1570 var newtype
= self.mtype
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1571 var res
= new MParameter(self.name
, newtype
, self.is_vararg
)
1575 redef fun model
do return mtype
.model
1578 # A service (global property) that generalize method, attribute, etc.
1580 # `MProperty` are global to the model; it means that a `MProperty` is not bound
1581 # to a specific `MModule` nor a specific `MClass`.
1583 # A MProperty gather definitions (see `mpropdefs`) ; one for the introduction
1584 # and the other in subclasses and in refinements.
1586 # A `MProperty` is used to denotes services in polymorphic way (ie. independent
1587 # of any dynamic type).
1588 # For instance, a call site "x.foo" is associated to a `MProperty`.
1589 abstract class MProperty
1592 # The associated MPropDef subclass.
1593 # The two specialization hierarchy are symmetric.
1594 type MPROPDEF: MPropDef
1596 # The classdef that introduce the property
1597 # While a property is not bound to a specific module, or class,
1598 # the introducing mclassdef is used for naming and visibility
1599 var intro_mclassdef
: MClassDef
1601 # The (short) name of the property
1602 redef var name
: String
1604 # The canonical name of the property
1605 # Example: "owner::my_module::MyClass::my_method"
1606 fun full_name
: String
1608 return "{self.intro_mclassdef.mmodule.full_name}::{self.intro_mclassdef.mclass.name}::{name}"
1611 # The visibility of the property
1612 var visibility
: MVisibility
1614 init(intro_mclassdef
: MClassDef, name
: String, visibility
: MVisibility)
1616 self.intro_mclassdef
= intro_mclassdef
1618 self.visibility
= visibility
1619 intro_mclassdef
.intro_mproperties
.add
(self)
1620 var model
= intro_mclassdef
.mmodule
.model
1621 model
.mproperties_by_name
.add_one
(name
, self)
1622 model
.mproperties
.add
(self)
1625 # All definitions of the property.
1626 # The first is the introduction,
1627 # The other are redefinitions (in refinements and in subclasses)
1628 var mpropdefs
: Array[MPROPDEF] = new Array[MPROPDEF]
1630 # The definition that introduced the property
1631 # Warning: the introduction is the first `MPropDef` object
1632 # associated to self. If self is just created without having any
1633 # associated definition, this method will abort
1634 fun intro
: MPROPDEF do return mpropdefs
.first
1636 redef fun model
do return intro
.model
1639 redef fun to_s
do return name
1641 # Return the most specific property definitions defined or inherited by a type.
1642 # The selection knows that refinement is stronger than specialization;
1643 # however, in case of conflict more than one property are returned.
1644 # If mtype does not know mproperty then an empty array is returned.
1646 # If you want the really most specific property, then look at `lookup_first_definition`
1647 fun lookup_definitions
(mmodule
: MModule, mtype
: MType): Array[MPROPDEF]
1649 assert not mtype
.need_anchor
1650 if mtype
isa MNullableType then mtype
= mtype
.mtype
1652 var cache
= self.lookup_definitions_cache
[mmodule
, mtype
]
1653 if cache
!= null then return cache
1655 #print "select prop {mproperty} for {mtype} in {self}"
1656 # First, select all candidates
1657 var candidates
= new Array[MPROPDEF]
1658 for mpropdef
in self.mpropdefs
do
1659 # If the definition is not imported by the module, then skip
1660 if not mmodule
.in_importation
<= mpropdef
.mclassdef
.mmodule
then continue
1661 # If the definition is not inherited by the type, then skip
1662 if not mtype
.is_subtype
(mmodule
, null, mpropdef
.mclassdef
.bound_mtype
) then continue
1664 candidates
.add
(mpropdef
)
1666 # Fast track for only one candidate
1667 if candidates
.length
<= 1 then
1668 self.lookup_definitions_cache
[mmodule
, mtype
] = candidates
1672 # Second, filter the most specific ones
1673 return select_most_specific
(mmodule
, candidates
)
1676 private var lookup_definitions_cache
: HashMap2[MModule, MType, Array[MPROPDEF]] = new HashMap2[MModule, MType, Array[MPROPDEF]]
1678 # Return the most specific property definitions inherited by a type.
1679 # The selection knows that refinement is stronger than specialization;
1680 # however, in case of conflict more than one property are returned.
1681 # If mtype does not know mproperty then an empty array is returned.
1683 # If you want the really most specific property, then look at `lookup_next_definition`
1685 # FIXME: Move to `MPropDef`?
1686 fun lookup_super_definitions
(mmodule
: MModule, mtype
: MType): Array[MPROPDEF]
1688 assert not mtype
.need_anchor
1689 if mtype
isa MNullableType then mtype
= mtype
.mtype
1691 # First, select all candidates
1692 var candidates
= new Array[MPROPDEF]
1693 for mpropdef
in self.mpropdefs
do
1694 # If the definition is not imported by the module, then skip
1695 if not mmodule
.in_importation
<= mpropdef
.mclassdef
.mmodule
then continue
1696 # If the definition is not inherited by the type, then skip
1697 if not mtype
.is_subtype
(mmodule
, null, mpropdef
.mclassdef
.bound_mtype
) then continue
1698 # If the definition is defined by the type, then skip (we want the super, so e skip the current)
1699 if mtype
== mpropdef
.mclassdef
.bound_mtype
and mmodule
== mpropdef
.mclassdef
.mmodule
then continue
1701 candidates
.add
(mpropdef
)
1703 # Fast track for only one candidate
1704 if candidates
.length
<= 1 then return candidates
1706 # Second, filter the most specific ones
1707 return select_most_specific
(mmodule
, candidates
)
1710 # Return an array containing olny the most specific property definitions
1711 # This is an helper function for `lookup_definitions` and `lookup_super_definitions`
1712 private fun select_most_specific
(mmodule
: MModule, candidates
: Array[MPROPDEF]): Array[MPROPDEF]
1714 var res
= new Array[MPROPDEF]
1715 for pd1
in candidates
do
1716 var cd1
= pd1
.mclassdef
1719 for pd2
in candidates
do
1720 if pd2
== pd1
then continue # do not compare with self!
1721 var cd2
= pd2
.mclassdef
1723 if c2
.mclass_type
== c1
.mclass_type
then
1724 if cd2
.mmodule
.in_importation
< cd1
.mmodule
then
1725 # cd2 refines cd1; therefore we skip pd1
1729 else if cd2
.bound_mtype
.is_subtype
(mmodule
, null, cd1
.bound_mtype
) and cd2
.bound_mtype
!= cd1
.bound_mtype
then
1730 # cd2 < cd1; therefore we skip pd1
1739 if res
.is_empty
then
1740 print
"All lost! {candidates.join(", ")}"
1741 # FIXME: should be abort!
1746 # Return the most specific definition in the linearization of `mtype`.
1748 # If you want to know the next properties in the linearization,
1749 # look at `MPropDef::lookup_next_definition`.
1751 # FIXME: the linearisation is still unspecified
1753 # REQUIRE: `not mtype.need_anchor`
1754 # REQUIRE: `mtype.has_mproperty(mmodule, self)`
1755 fun lookup_first_definition
(mmodule
: MModule, mtype
: MType): MPROPDEF
1757 assert mtype
.has_mproperty
(mmodule
, self)
1758 return lookup_all_definitions
(mmodule
, mtype
).first
1761 # Return all definitions in a linearisation order
1762 # Most speficic first, most general last
1763 fun lookup_all_definitions
(mmodule
: MModule, mtype
: MType): Array[MPROPDEF]
1765 assert not mtype
.need_anchor
1766 if mtype
isa MNullableType then mtype
= mtype
.mtype
1768 var cache
= self.lookup_all_definitions_cache
[mmodule
, mtype
]
1769 if cache
!= null then return cache
1771 #print "select prop {mproperty} for {mtype} in {self}"
1772 # First, select all candidates
1773 var candidates
= new Array[MPROPDEF]
1774 for mpropdef
in self.mpropdefs
do
1775 # If the definition is not imported by the module, then skip
1776 if not mmodule
.in_importation
<= mpropdef
.mclassdef
.mmodule
then continue
1777 # If the definition is not inherited by the type, then skip
1778 if not mtype
.is_subtype
(mmodule
, null, mpropdef
.mclassdef
.bound_mtype
) then continue
1780 candidates
.add
(mpropdef
)
1782 # Fast track for only one candidate
1783 if candidates
.length
<= 1 then
1784 self.lookup_all_definitions_cache
[mmodule
, mtype
] = candidates
1788 mmodule
.linearize_mpropdefs
(candidates
)
1789 candidates
= candidates
.reversed
1790 self.lookup_all_definitions_cache
[mmodule
, mtype
] = candidates
1794 private var lookup_all_definitions_cache
: HashMap2[MModule, MType, Array[MPROPDEF]] = new HashMap2[MModule, MType, Array[MPROPDEF]]
1801 redef type MPROPDEF: MMethodDef
1803 init(intro_mclassdef
: MClassDef, name
: String, visibility
: MVisibility)
1808 # Is the property defined at the top_level of the module?
1809 # Currently such a property are stored in `Object`
1810 var is_toplevel
: Bool writable = false
1812 # Is the property a constructor?
1813 # Warning, this property can be inherited by subclasses with or without being a constructor
1814 # therefore, you should use `is_init_for` the verify if the property is a legal constructor for a given class
1815 var is_init
: Bool writable = false
1817 # The the property a 'new' contructor?
1818 var is_new
: Bool writable = false
1820 # Is the property a legal constructor for a given class?
1821 # As usual, visibility is not considered.
1822 # FIXME not implemented
1823 fun is_init_for
(mclass
: MClass): Bool
1829 # A global attribute
1833 redef type MPROPDEF: MAttributeDef
1835 init(intro_mclassdef
: MClassDef, name
: String, visibility
: MVisibility)
1841 # A global virtual type
1842 class MVirtualTypeProp
1845 redef type MPROPDEF: MVirtualTypeDef
1847 init(intro_mclassdef
: MClassDef, name
: String, visibility
: MVisibility)
1852 # The formal type associated to the virtual type property
1853 var mvirtualtype
: MVirtualType = new MVirtualType(self)
1856 # A definition of a property (local property)
1858 # Unlike `MProperty`, a `MPropDef` is a local definition that belong to a
1859 # specific class definition (which belong to a specific module)
1860 abstract class MPropDef
1863 # The associated `MProperty` subclass.
1864 # the two specialization hierarchy are symmetric
1865 type MPROPERTY: MProperty
1868 type MPROPDEF: MPropDef
1870 # The origin of the definition
1871 var location
: Location
1873 # The class definition where the property definition is
1874 var mclassdef
: MClassDef
1876 # The associated global property
1877 var mproperty
: MPROPERTY
1879 init(mclassdef
: MClassDef, mproperty
: MPROPERTY, location
: Location)
1881 self.mclassdef
= mclassdef
1882 self.mproperty
= mproperty
1883 self.location
= location
1884 mclassdef
.mpropdefs
.add
(self)
1885 mproperty
.mpropdefs
.add
(self)
1886 self.to_s
= "{mclassdef}#{mproperty}"
1889 # Actually the name of the `mproperty`
1890 redef fun name
do return mproperty
.name
1892 redef fun model
do return mclassdef
.model
1894 # Internal name combining the module, the class and the property
1895 # Example: "mymodule#MyClass#mymethod"
1896 redef var to_s
: String
1898 # Is self the definition that introduce the property?
1899 fun is_intro
: Bool do return mproperty
.intro
== self
1901 # Return the next definition in linearization of `mtype`.
1903 # This method is used to determine what method is called by a super.
1905 # REQUIRE: `not mtype.need_anchor`
1906 fun lookup_next_definition
(mmodule
: MModule, mtype
: MType): MPROPDEF
1908 assert not mtype
.need_anchor
1910 var mpropdefs
= self.mproperty
.lookup_all_definitions
(mmodule
, mtype
)
1911 var i
= mpropdefs
.iterator
1912 while i
.is_ok
and i
.item
!= self do i
.next
1913 assert has_property
: i
.is_ok
1915 assert has_next_property
: i
.is_ok
1920 # A local definition of a method
1924 redef type MPROPERTY: MMethod
1925 redef type MPROPDEF: MMethodDef
1927 init(mclassdef
: MClassDef, mproperty
: MPROPERTY, location
: Location)
1932 # The signature attached to the property definition
1933 var msignature
: nullable MSignature writable = null
1935 # Is the method definition abstract?
1936 var is_abstract
: Bool writable = false
1938 # Is the method definition intern?
1939 var is_intern
writable = false
1941 # Is the method definition extern?
1942 var is_extern
writable = false
1945 # A local definition of an attribute
1949 redef type MPROPERTY: MAttribute
1950 redef type MPROPDEF: MAttributeDef
1952 init(mclassdef
: MClassDef, mproperty
: MPROPERTY, location
: Location)
1957 # The static type of the attribute
1958 var static_mtype
: nullable MType writable = null
1961 # A local definition of a virtual type
1962 class MVirtualTypeDef
1965 redef type MPROPERTY: MVirtualTypeProp
1966 redef type MPROPDEF: MVirtualTypeDef
1968 init(mclassdef
: MClassDef, mproperty
: MPROPERTY, location
: Location)
1973 # The bound of the virtual type
1974 var bound
: nullable MType writable = null
1976 # Is the bound fixed?
1977 var is_fixed
writable = false
1984 # * `interface_kind`
1988 # Note this class is basically an enum.
1989 # FIXME: use a real enum once user-defined enums are available
1991 redef var to_s
: String
1993 # Is a constructor required?
1995 private init(s
: String, need_init
: Bool)
1998 self.need_init
= need_init
2001 # Can a class of kind `self` specializes a class of kine `other`?
2002 fun can_specialize
(other
: MClassKind): Bool
2004 if other
== interface_kind
then return true # everybody can specialize interfaces
2005 if self == interface_kind
or self == enum_kind
then
2006 # no other case for interfaces
2008 else if self == extern_kind
then
2009 # only compatible with themselve
2010 return self == other
2011 else if other
== enum_kind
or other
== extern_kind
then
2012 # abstract_kind and concrete_kind are incompatible
2015 # remain only abstract_kind and concrete_kind
2020 fun abstract_kind
: MClassKind do return once
new MClassKind("abstract class", true)
2021 fun concrete_kind
: MClassKind do return once
new MClassKind("class", true)
2022 fun interface_kind
: MClassKind do return once
new MClassKind("interface", false)
2023 fun enum_kind
: MClassKind do return once
new MClassKind("enum", false)
2024 fun extern_kind
: MClassKind do return once
new MClassKind("extern class", false)