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 private var as_nullable_cache
: nullable MType = null
893 # The deph of the type seen as a tree.
900 # Formal types have a depth of 1.
906 # The length of the type seen as a tree.
913 # Formal types have a length of 1.
919 # Compute all the classdefs inherited/imported.
920 # The returned set contains:
921 # * the class definitions from `mmodule` and its imported modules
922 # * the class definitions of this type and its super-types
924 # This function is used mainly internally.
926 # REQUIRE: `not self.need_anchor`
927 fun collect_mclassdefs
(mmodule
: MModule): Set[MClassDef] is abstract
929 # Compute all the super-classes.
930 # This function is used mainly internally.
932 # REQUIRE: `not self.need_anchor`
933 fun collect_mclasses
(mmodule
: MModule): Set[MClass] is abstract
935 # Compute all the declared super-types.
936 # Super-types are returned as declared in the classdefs (verbatim).
937 # This function is used mainly internally.
939 # REQUIRE: `not self.need_anchor`
940 fun collect_mtypes
(mmodule
: MModule): Set[MClassType] is abstract
942 # Is the property in self for a given module
943 # This method does not filter visibility or whatever
945 # REQUIRE: `not self.need_anchor`
946 fun has_mproperty
(mmodule
: MModule, mproperty
: MProperty): Bool
948 assert not self.need_anchor
949 return self.collect_mclassdefs
(mmodule
).has
(mproperty
.intro_mclassdef
)
953 # A type based on a class.
955 # `MClassType` have properties (see `has_mproperty`).
959 # The associated class
962 redef fun model
do return self.mclass
.intro_mmodule
.model
964 private init(mclass
: MClass)
969 # The formal arguments of the type
970 # ENSURE: `result.length == self.mclass.arity`
971 var arguments
: Array[MType] = new Array[MType]
973 redef fun to_s
do return mclass
.to_s
975 redef fun need_anchor
do return false
977 redef fun anchor_to
(mmodule
: MModule, anchor
: MClassType): MClassType
979 return super.as(MClassType)
982 redef fun resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule, cleanup_virtual
: Bool): MClassType do return self
984 redef fun can_resolve_for
(mtype
, anchor
, mmodule
) do return true
986 redef fun collect_mclassdefs
(mmodule
)
988 assert not self.need_anchor
989 var cache
= self.collect_mclassdefs_cache
990 if not cache
.has_key
(mmodule
) then
991 self.collect_things
(mmodule
)
993 return cache
[mmodule
]
996 redef fun collect_mclasses
(mmodule
)
998 assert not self.need_anchor
999 var cache
= self.collect_mclasses_cache
1000 if not cache
.has_key
(mmodule
) then
1001 self.collect_things
(mmodule
)
1003 return cache
[mmodule
]
1006 redef fun collect_mtypes
(mmodule
)
1008 assert not self.need_anchor
1009 var cache
= self.collect_mtypes_cache
1010 if not cache
.has_key
(mmodule
) then
1011 self.collect_things
(mmodule
)
1013 return cache
[mmodule
]
1016 # common implementation for `collect_mclassdefs`, `collect_mclasses`, and `collect_mtypes`.
1017 private fun collect_things
(mmodule
: MModule)
1019 var res
= new HashSet[MClassDef]
1020 var seen
= new HashSet[MClass]
1021 var types
= new HashSet[MClassType]
1022 seen
.add
(self.mclass
)
1023 var todo
= [self.mclass
]
1024 while not todo
.is_empty
do
1025 var mclass
= todo
.pop
1026 #print "process {mclass}"
1027 for mclassdef
in mclass
.mclassdefs
do
1028 if not mmodule
.in_importation
<= mclassdef
.mmodule
then continue
1029 #print " process {mclassdef}"
1031 for supertype
in mclassdef
.supertypes
do
1032 types
.add
(supertype
)
1033 var superclass
= supertype
.mclass
1034 if seen
.has
(superclass
) then continue
1035 #print " add {superclass}"
1036 seen
.add
(superclass
)
1037 todo
.add
(superclass
)
1041 collect_mclassdefs_cache
[mmodule
] = res
1042 collect_mclasses_cache
[mmodule
] = seen
1043 collect_mtypes_cache
[mmodule
] = types
1046 private var collect_mclassdefs_cache
: HashMap[MModule, Set[MClassDef]] = new HashMap[MModule, Set[MClassDef]]
1047 private var collect_mclasses_cache
: HashMap[MModule, Set[MClass]] = new HashMap[MModule, Set[MClass]]
1048 private var collect_mtypes_cache
: HashMap[MModule, Set[MClassType]] = new HashMap[MModule, Set[MClassType]]
1052 # A type based on a generic class.
1053 # A generic type a just a class with additional formal generic arguments.
1057 private init(mclass
: MClass, arguments
: Array[MType])
1060 assert self.mclass
.arity
== arguments
.length
1061 self.arguments
= arguments
1063 self.need_anchor
= false
1064 for t
in arguments
do
1065 if t
.need_anchor
then
1066 self.need_anchor
= true
1071 self.to_s
= "{mclass}[{arguments.join(", ")}]"
1074 # Recursively print the type of the arguments within brackets.
1075 # Example: `"Map[String, List[Int]]"`
1076 redef var to_s
: String
1078 redef var need_anchor
: Bool
1080 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1082 if not need_anchor
then return self
1083 assert can_resolve_for
(mtype
, anchor
, mmodule
)
1084 var types
= new Array[MType]
1085 for t
in arguments
do
1086 types
.add
(t
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
))
1088 return mclass
.get_mtype
(types
)
1091 redef fun can_resolve_for
(mtype
, anchor
, mmodule
)
1093 if not need_anchor
then return true
1094 for t
in arguments
do
1095 if not t
.can_resolve_for
(mtype
, anchor
, mmodule
) then return false
1104 for a
in self.arguments
do
1106 if d
> dmax
then dmax
= d
1114 for a
in self.arguments
do
1121 # A virtual formal type.
1125 # The property associated with the type.
1126 # Its the definitions of this property that determine the bound or the virtual type.
1127 var mproperty
: MProperty
1129 redef fun model
do return self.mproperty
.intro_mclassdef
.mmodule
.model
1131 # Lookup the bound for a given resolved_receiver
1132 # The result may be a other virtual type (or a parameter type)
1134 # The result is returned exactly as declared in the "type" property (verbatim).
1136 # In case of conflict, the method aborts.
1137 fun lookup_bound
(mmodule
: MModule, resolved_receiver
: MType): MType
1139 assert not resolved_receiver
.need_anchor
1140 var props
= self.mproperty
.lookup_definitions
(mmodule
, resolved_receiver
)
1141 if props
.is_empty
then
1143 else if props
.length
== 1 then
1144 return props
.first
.as(MVirtualTypeDef).bound
.as(not null)
1146 var types
= new ArraySet[MType]
1148 types
.add
(p
.as(MVirtualTypeDef).bound
.as(not null))
1150 if types
.length
== 1 then
1156 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1158 assert can_resolve_for
(mtype
, anchor
, mmodule
)
1159 # self is a virtual type declared (or inherited) in mtype
1160 # The point of the function it to get the bound of the virtual type that make sense for mtype
1161 # But because mtype is maybe a virtual/formal type, we need to get a real receiver first
1162 #print "{class_name}: {self}/{mtype}/{anchor}?"
1163 var resolved_reciever
1164 if mtype
.need_anchor
then
1165 assert anchor
!= null
1166 resolved_reciever
= mtype
.resolve_for
(anchor
, null, mmodule
, true)
1168 resolved_reciever
= mtype
1170 # Now, we can get the bound
1171 var verbatim_bound
= lookup_bound
(mmodule
, resolved_reciever
)
1172 # The bound is exactly as declared in the "type" property, so we must resolve it again
1173 var res
= verbatim_bound
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1174 #print "{class_name}: {self}/{mtype}/{anchor} -> {self}/{resolved_reciever}/{anchor} -> {verbatim_bound}/{mtype}/{anchor} -> {res}"
1176 # What to return here? There is a bunch a special cases:
1177 # If 'cleanup_virtual' we must return the resolved type, since we cannot return self
1178 if cleanup_virtual
then return res
1179 # 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
1180 if resolved_reciever
isa MNullableType then resolved_reciever
= resolved_reciever
.mtype
1181 if resolved_reciever
.as(MClassType).mclass
.kind
== enum_kind
then return res
1182 # 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.
1183 if res
isa MVirtualType then return res
1184 # 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
1185 if res
isa MClassType and res
.mclass
.kind
== enum_kind
then return res
1186 # TODO: Add 'fixed' virtual type in the specification.
1187 # TODO: What if bound to a MParameterType?
1188 # Note that Nullable types can always be redefined by the non nullable version, so there is no specific case on it.
1190 # If anything apply, then `self' cannot be resolved, so return self
1194 redef fun can_resolve_for
(mtype
, anchor
, mmodule
)
1196 if mtype
.need_anchor
then
1197 assert anchor
!= null
1198 mtype
= mtype
.anchor_to
(mmodule
, anchor
)
1200 return mtype
.has_mproperty
(mmodule
, mproperty
)
1203 redef fun to_s
do return self.mproperty
.to_s
1205 init(mproperty
: MProperty)
1207 self.mproperty
= mproperty
1211 # The type associated the a formal parameter generic type of a class
1213 # Each parameter type is associated to a specific class.
1214 # It's mean that all refinements of a same class "share" the parameter type,
1215 # but that a generic subclass has its on parameter types.
1217 # However, in the sense of the meta-model, a parameter type of a class is
1218 # a valid type in a subclass. The "in the sense of the meta-model" is
1219 # important because, in the Nit language, the programmer cannot refers
1220 # directly to the parameter types of the super-classes.
1224 # fun e: E is abstract
1229 # In the class definition B[F], `F` is a valid type but `E` is not.
1230 # However, `self.e` is a valid method call, and the signature of `e` is
1233 # Note that parameter types are shared among class refinements.
1234 # Therefore parameter only have an internal name (see `to_s` for details).
1235 # TODO: Add a `name_for` to get better messages.
1236 class MParameterType
1239 # The generic class where the parameter belong
1242 redef fun model
do return self.mclass
.intro_mmodule
.model
1244 # The position of the parameter (0 for the first parameter)
1245 # FIXME: is `position` a better name?
1248 # Internal name of the parameter type
1249 # Names of parameter types changes in each class definition
1250 # Therefore, this method return an internal name.
1251 # Example: return "G#1" for the second parameter of the class G
1252 # FIXME: add a way to get the real name in a classdef
1253 redef fun to_s
do return "{mclass}#{rank}"
1255 # Resolve the bound for a given resolved_receiver
1256 # The result may be a other virtual type (or a parameter type)
1257 fun lookup_bound
(mmodule
: MModule, resolved_receiver
: MType): MType
1259 assert not resolved_receiver
.need_anchor
1260 var goalclass
= self.mclass
1261 var supertypes
= resolved_receiver
.collect_mtypes
(mmodule
)
1262 for t
in supertypes
do
1263 if t
.mclass
== goalclass
then
1264 # Yeah! c specialize goalclass with a "super `t'". So the question is what is the argument of f
1265 # FIXME: Here, we stop on the first goal. Should we check others and detect inconsistencies?
1266 var res
= t
.arguments
[self.rank
]
1273 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1275 assert can_resolve_for
(mtype
, anchor
, mmodule
)
1276 #print "{class_name}: {self}/{mtype}/{anchor}?"
1278 if mtype
isa MGenericType and mtype
.mclass
== self.mclass
then
1279 return mtype
.arguments
[self.rank
]
1282 # self is a parameter type of mtype (or of a super-class of mtype)
1283 # The point of the function it to get the bound of the virtual type that make sense for mtype
1284 # But because mtype is maybe a virtual/formal type, we need to get a real receiver first
1285 # FIXME: What happend here is far from clear. Thus this part must be validated and clarified
1286 var resolved_receiver
1287 if mtype
.need_anchor
then
1288 assert anchor
!= null
1289 resolved_receiver
= mtype
.resolve_for
(anchor
.mclass
.mclass_type
, anchor
, mmodule
, true)
1291 resolved_receiver
= mtype
1293 if resolved_receiver
isa MNullableType then resolved_receiver
= resolved_receiver
.mtype
1294 if resolved_receiver
isa MParameterType then
1295 assert resolved_receiver
.mclass
== anchor
.mclass
1296 resolved_receiver
= anchor
.arguments
[resolved_receiver
.rank
]
1297 if resolved_receiver
isa MNullableType then resolved_receiver
= resolved_receiver
.mtype
1299 assert resolved_receiver
isa MClassType
1301 # Eh! The parameter is in the current class.
1302 # So we return the corresponding argument, no mater what!
1303 if resolved_receiver
.mclass
== self.mclass
then
1304 var res
= resolved_receiver
.arguments
[self.rank
]
1305 #print "{class_name}: {self}/{mtype}/{anchor} -> direct {res}"
1309 if resolved_receiver
.need_anchor
then
1310 assert anchor
!= null
1311 resolved_receiver
= resolved_receiver
.resolve_for
(anchor
, null, mmodule
, false)
1313 # Now, we can get the bound
1314 var verbatim_bound
= lookup_bound
(mmodule
, resolved_receiver
)
1315 # The bound is exactly as declared in the "type" property, so we must resolve it again
1316 var res
= verbatim_bound
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1318 #print "{class_name}: {self}/{mtype}/{anchor} -> indirect {res}"
1323 redef fun can_resolve_for
(mtype
, anchor
, mmodule
)
1325 if mtype
.need_anchor
then
1326 assert anchor
!= null
1327 mtype
= mtype
.anchor_to
(mmodule
, anchor
)
1329 return mtype
.collect_mclassdefs
(mmodule
).has
(mclass
.intro
)
1332 init(mclass
: MClass, rank
: Int)
1334 self.mclass
= mclass
1339 # A type prefixed with "nullable"
1343 # The base type of the nullable type
1346 redef fun model
do return self.mtype
.model
1351 self.to_s
= "nullable {mtype}"
1354 redef var to_s
: String
1356 redef fun need_anchor
do return mtype
.need_anchor
1357 redef fun as_nullable
do return self
1358 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1360 var res
= self.mtype
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1361 return res
.as_nullable
1364 redef fun can_resolve_for
(mtype
, anchor
, mmodule
)
1366 return self.mtype
.can_resolve_for
(mtype
, anchor
, mmodule
)
1369 redef fun depth
do return self.mtype
.depth
1371 redef fun length
do return self.mtype
.length
1373 redef fun collect_mclassdefs
(mmodule
)
1375 assert not self.need_anchor
1376 return self.mtype
.collect_mclassdefs
(mmodule
)
1379 redef fun collect_mclasses
(mmodule
)
1381 assert not self.need_anchor
1382 return self.mtype
.collect_mclasses
(mmodule
)
1385 redef fun collect_mtypes
(mmodule
)
1387 assert not self.need_anchor
1388 return self.mtype
.collect_mtypes
(mmodule
)
1392 # The type of the only value null
1394 # The is only one null type per model, see `MModel::null_type`.
1397 redef var model
: Model
1398 protected init(model
: Model)
1402 redef fun to_s
do return "null"
1403 redef fun as_nullable
do return self
1404 redef fun need_anchor
do return false
1405 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
) do return self
1406 redef fun can_resolve_for
(mtype
, anchor
, mmodule
) do return true
1408 redef fun collect_mclassdefs
(mmodule
) do return new HashSet[MClassDef]
1410 redef fun collect_mclasses
(mmodule
) do return new HashSet[MClass]
1412 redef fun collect_mtypes
(mmodule
) do return new HashSet[MClassType]
1415 # A signature of a method
1419 # The each parameter (in order)
1420 var mparameters
: Array[MParameter]
1422 # The return type (null for a procedure)
1423 var return_mtype
: nullable MType
1428 var t
= self.return_mtype
1429 if t
!= null then dmax
= t
.depth
1430 for p
in mparameters
do
1431 var d
= p
.mtype
.depth
1432 if d
> dmax
then dmax
= d
1440 var t
= self.return_mtype
1441 if t
!= null then res
+= t
.length
1442 for p
in mparameters
do
1443 res
+= p
.mtype
.length
1448 # REQUIRE: 1 <= mparameters.count p -> p.is_vararg
1449 init(mparameters
: Array[MParameter], return_mtype
: nullable MType)
1451 var vararg_rank
= -1
1452 for i
in [0..mparameters
.length
[ do
1453 var parameter
= mparameters
[i
]
1454 if parameter
.is_vararg
then
1455 assert vararg_rank
== -1
1459 self.mparameters
= mparameters
1460 self.return_mtype
= return_mtype
1461 self.vararg_rank
= vararg_rank
1464 # The rank of the ellipsis (`...`) for vararg (starting from 0).
1465 # value is -1 if there is no vararg.
1466 # Example: for "(a: Int, b: Bool..., c: Char)" #-> vararg_rank=1
1467 var vararg_rank
: Int
1469 # The number or parameters
1470 fun arity
: Int do return mparameters
.length
1474 var b
= new FlatBuffer
1475 if not mparameters
.is_empty
then
1477 for i
in [0..mparameters
.length
[ do
1478 var mparameter
= mparameters
[i
]
1479 if i
> 0 then b
.append
(", ")
1480 b
.append
(mparameter
.name
)
1482 b
.append
(mparameter
.mtype
.to_s
)
1483 if mparameter
.is_vararg
then
1489 var ret
= self.return_mtype
1497 redef fun resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule, cleanup_virtual
: Bool): MSignature
1499 var params
= new Array[MParameter]
1500 for p
in self.mparameters
do
1501 params
.add
(p
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
))
1503 var ret
= self.return_mtype
1505 ret
= ret
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1507 var res
= new MSignature(params
, ret
)
1512 # A parameter in a signature
1516 # The name of the parameter
1517 redef var name
: String
1519 # The static type of the parameter
1522 # Is the parameter a vararg?
1525 init(name
: String, mtype
: MType, is_vararg
: Bool) do
1528 self.is_vararg
= is_vararg
1534 return "{name}: {mtype}..."
1536 return "{name}: {mtype}"
1540 fun resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule, cleanup_virtual
: Bool): MParameter
1542 if not self.mtype
.need_anchor
then return self
1543 var newtype
= self.mtype
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1544 var res
= new MParameter(self.name
, newtype
, self.is_vararg
)
1548 redef fun model
do return mtype
.model
1551 # A service (global property) that generalize method, attribute, etc.
1553 # `MProperty` are global to the model; it means that a `MProperty` is not bound
1554 # to a specific `MModule` nor a specific `MClass`.
1556 # A MProperty gather definitions (see `mpropdefs`) ; one for the introduction
1557 # and the other in subclasses and in refinements.
1559 # A `MProperty` is used to denotes services in polymorphic way (ie. independent
1560 # of any dynamic type).
1561 # For instance, a call site "x.foo" is associated to a `MProperty`.
1562 abstract class MProperty
1565 # The associated MPropDef subclass.
1566 # The two specialization hierarchy are symmetric.
1567 type MPROPDEF: MPropDef
1569 # The classdef that introduce the property
1570 # While a property is not bound to a specific module, or class,
1571 # the introducing mclassdef is used for naming and visibility
1572 var intro_mclassdef
: MClassDef
1574 # The (short) name of the property
1575 redef var name
: String
1577 # The canonical name of the property
1578 # Example: "owner::my_module::MyClass::my_method"
1579 fun full_name
: String
1581 return "{self.intro_mclassdef.mmodule.full_name}::{self.intro_mclassdef.mclass.name}::{name}"
1584 # The visibility of the property
1585 var visibility
: MVisibility
1587 init(intro_mclassdef
: MClassDef, name
: String, visibility
: MVisibility)
1589 self.intro_mclassdef
= intro_mclassdef
1591 self.visibility
= visibility
1592 intro_mclassdef
.intro_mproperties
.add
(self)
1593 var model
= intro_mclassdef
.mmodule
.model
1594 model
.mproperties_by_name
.add_one
(name
, self)
1595 model
.mproperties
.add
(self)
1598 # All definitions of the property.
1599 # The first is the introduction,
1600 # The other are redefinitions (in refinements and in subclasses)
1601 var mpropdefs
: Array[MPROPDEF] = new Array[MPROPDEF]
1603 # The definition that introduced the property
1604 # Warning: the introduction is the first `MPropDef` object
1605 # associated to self. If self is just created without having any
1606 # associated definition, this method will abort
1607 fun intro
: MPROPDEF do return mpropdefs
.first
1609 redef fun model
do return intro
.model
1612 redef fun to_s
do return name
1614 # Return the most specific property definitions defined or inherited by a type.
1615 # The selection knows that refinement is stronger than specialization;
1616 # however, in case of conflict more than one property are returned.
1617 # If mtype does not know mproperty then an empty array is returned.
1619 # If you want the really most specific property, then look at `lookup_first_definition`
1620 fun lookup_definitions
(mmodule
: MModule, mtype
: MType): Array[MPROPDEF]
1622 assert not mtype
.need_anchor
1623 if mtype
isa MNullableType then mtype
= mtype
.mtype
1625 var cache
= self.lookup_definitions_cache
[mmodule
, mtype
]
1626 if cache
!= null then return cache
1628 #print "select prop {mproperty} for {mtype} in {self}"
1629 # First, select all candidates
1630 var candidates
= new Array[MPROPDEF]
1631 for mpropdef
in self.mpropdefs
do
1632 # If the definition is not imported by the module, then skip
1633 if not mmodule
.in_importation
<= mpropdef
.mclassdef
.mmodule
then continue
1634 # If the definition is not inherited by the type, then skip
1635 if not mtype
.is_subtype
(mmodule
, null, mpropdef
.mclassdef
.bound_mtype
) then continue
1637 candidates
.add
(mpropdef
)
1639 # Fast track for only one candidate
1640 if candidates
.length
<= 1 then
1641 self.lookup_definitions_cache
[mmodule
, mtype
] = candidates
1645 # Second, filter the most specific ones
1646 return select_most_specific
(mmodule
, candidates
)
1649 private var lookup_definitions_cache
: HashMap2[MModule, MType, Array[MPROPDEF]] = new HashMap2[MModule, MType, Array[MPROPDEF]]
1651 # Return the most specific property definitions inherited by a type.
1652 # The selection knows that refinement is stronger than specialization;
1653 # however, in case of conflict more than one property are returned.
1654 # If mtype does not know mproperty then an empty array is returned.
1656 # If you want the really most specific property, then look at `lookup_next_definition`
1658 # FIXME: Move to `MPropDef`?
1659 fun lookup_super_definitions
(mmodule
: MModule, mtype
: MType): Array[MPROPDEF]
1661 assert not mtype
.need_anchor
1662 if mtype
isa MNullableType then mtype
= mtype
.mtype
1664 # First, select all candidates
1665 var candidates
= new Array[MPROPDEF]
1666 for mpropdef
in self.mpropdefs
do
1667 # If the definition is not imported by the module, then skip
1668 if not mmodule
.in_importation
<= mpropdef
.mclassdef
.mmodule
then continue
1669 # If the definition is not inherited by the type, then skip
1670 if not mtype
.is_subtype
(mmodule
, null, mpropdef
.mclassdef
.bound_mtype
) then continue
1671 # If the definition is defined by the type, then skip (we want the super, so e skip the current)
1672 if mtype
== mpropdef
.mclassdef
.bound_mtype
and mmodule
== mpropdef
.mclassdef
.mmodule
then continue
1674 candidates
.add
(mpropdef
)
1676 # Fast track for only one candidate
1677 if candidates
.length
<= 1 then return candidates
1679 # Second, filter the most specific ones
1680 return select_most_specific
(mmodule
, candidates
)
1683 # Return an array containing olny the most specific property definitions
1684 # This is an helper function for `lookup_definitions` and `lookup_super_definitions`
1685 private fun select_most_specific
(mmodule
: MModule, candidates
: Array[MPROPDEF]): Array[MPROPDEF]
1687 var res
= new Array[MPROPDEF]
1688 for pd1
in candidates
do
1689 var cd1
= pd1
.mclassdef
1692 for pd2
in candidates
do
1693 if pd2
== pd1
then continue # do not compare with self!
1694 var cd2
= pd2
.mclassdef
1696 if c2
.mclass_type
== c1
.mclass_type
then
1697 if cd2
.mmodule
.in_importation
< cd1
.mmodule
then
1698 # cd2 refines cd1; therefore we skip pd1
1702 else if cd2
.bound_mtype
.is_subtype
(mmodule
, null, cd1
.bound_mtype
) and cd2
.bound_mtype
!= cd1
.bound_mtype
then
1703 # cd2 < cd1; therefore we skip pd1
1712 if res
.is_empty
then
1713 print
"All lost! {candidates.join(", ")}"
1714 # FIXME: should be abort!
1719 # Return the most specific definition in the linearization of `mtype`.
1721 # If you want to know the next properties in the linearization,
1722 # look at `MPropDef::lookup_next_definition`.
1724 # FIXME: the linearisation is still unspecified
1726 # REQUIRE: `not mtype.need_anchor`
1727 # REQUIRE: `mtype.has_mproperty(mmodule, self)`
1728 fun lookup_first_definition
(mmodule
: MModule, mtype
: MType): MPROPDEF
1730 assert mtype
.has_mproperty
(mmodule
, self)
1731 return lookup_all_definitions
(mmodule
, mtype
).first
1734 # Return all definitions in a linearisation order
1735 # Most speficic first, most general last
1736 fun lookup_all_definitions
(mmodule
: MModule, mtype
: MType): Array[MPROPDEF]
1738 assert not mtype
.need_anchor
1739 if mtype
isa MNullableType then mtype
= mtype
.mtype
1741 var cache
= self.lookup_all_definitions_cache
[mmodule
, mtype
]
1742 if cache
!= null then return cache
1744 #print "select prop {mproperty} for {mtype} in {self}"
1745 # First, select all candidates
1746 var candidates
= new Array[MPROPDEF]
1747 for mpropdef
in self.mpropdefs
do
1748 # If the definition is not imported by the module, then skip
1749 if not mmodule
.in_importation
<= mpropdef
.mclassdef
.mmodule
then continue
1750 # If the definition is not inherited by the type, then skip
1751 if not mtype
.is_subtype
(mmodule
, null, mpropdef
.mclassdef
.bound_mtype
) then continue
1753 candidates
.add
(mpropdef
)
1755 # Fast track for only one candidate
1756 if candidates
.length
<= 1 then
1757 self.lookup_all_definitions_cache
[mmodule
, mtype
] = candidates
1761 mmodule
.linearize_mpropdefs
(candidates
)
1762 candidates
= candidates
.reversed
1763 self.lookup_all_definitions_cache
[mmodule
, mtype
] = candidates
1767 private var lookup_all_definitions_cache
: HashMap2[MModule, MType, Array[MPROPDEF]] = new HashMap2[MModule, MType, Array[MPROPDEF]]
1774 redef type MPROPDEF: MMethodDef
1776 init(intro_mclassdef
: MClassDef, name
: String, visibility
: MVisibility)
1781 # Is the property defined at the top_level of the module?
1782 # Currently such a property are stored in `Object`
1783 var is_toplevel
: Bool writable = false
1785 # Is the property a constructor?
1786 # Warning, this property can be inherited by subclasses with or without being a constructor
1787 # therefore, you should use `is_init_for` the verify if the property is a legal constructor for a given class
1788 var is_init
: Bool writable = false
1790 # The the property a 'new' contructor?
1791 var is_new
: Bool writable = false
1793 # Is the property a legal constructor for a given class?
1794 # As usual, visibility is not considered.
1795 # FIXME not implemented
1796 fun is_init_for
(mclass
: MClass): Bool
1802 # A global attribute
1806 redef type MPROPDEF: MAttributeDef
1808 init(intro_mclassdef
: MClassDef, name
: String, visibility
: MVisibility)
1814 # A global virtual type
1815 class MVirtualTypeProp
1818 redef type MPROPDEF: MVirtualTypeDef
1820 init(intro_mclassdef
: MClassDef, name
: String, visibility
: MVisibility)
1825 # The formal type associated to the virtual type property
1826 var mvirtualtype
: MVirtualType = new MVirtualType(self)
1829 # A definition of a property (local property)
1831 # Unlike `MProperty`, a `MPropDef` is a local definition that belong to a
1832 # specific class definition (which belong to a specific module)
1833 abstract class MPropDef
1836 # The associated `MProperty` subclass.
1837 # the two specialization hierarchy are symmetric
1838 type MPROPERTY: MProperty
1841 type MPROPDEF: MPropDef
1843 # The origin of the definition
1844 var location
: Location
1846 # The class definition where the property definition is
1847 var mclassdef
: MClassDef
1849 # The associated global property
1850 var mproperty
: MPROPERTY
1852 init(mclassdef
: MClassDef, mproperty
: MPROPERTY, location
: Location)
1854 self.mclassdef
= mclassdef
1855 self.mproperty
= mproperty
1856 self.location
= location
1857 mclassdef
.mpropdefs
.add
(self)
1858 mproperty
.mpropdefs
.add
(self)
1859 self.to_s
= "{mclassdef}#{mproperty}"
1862 # Actually the name of the `mproperty`
1863 redef fun name
do return mproperty
.name
1865 redef fun model
do return mclassdef
.model
1867 # Internal name combining the module, the class and the property
1868 # Example: "mymodule#MyClass#mymethod"
1869 redef var to_s
: String
1871 # Is self the definition that introduce the property?
1872 fun is_intro
: Bool do return mproperty
.intro
== self
1874 # Return the next definition in linearization of `mtype`.
1876 # This method is used to determine what method is called by a super.
1878 # REQUIRE: `not mtype.need_anchor`
1879 fun lookup_next_definition
(mmodule
: MModule, mtype
: MType): MPROPDEF
1881 assert not mtype
.need_anchor
1883 var mpropdefs
= self.mproperty
.lookup_all_definitions
(mmodule
, mtype
)
1884 var i
= mpropdefs
.iterator
1885 while i
.is_ok
and i
.item
!= self do i
.next
1886 assert has_property
: i
.is_ok
1888 assert has_next_property
: i
.is_ok
1893 # A local definition of a method
1897 redef type MPROPERTY: MMethod
1898 redef type MPROPDEF: MMethodDef
1900 init(mclassdef
: MClassDef, mproperty
: MPROPERTY, location
: Location)
1905 # The signature attached to the property definition
1906 var msignature
: nullable MSignature writable = null
1908 # Is the method definition abstract?
1909 var is_abstract
: Bool writable = false
1911 # Is the method definition intern?
1912 var is_intern
writable = false
1914 # Is the method definition extern?
1915 var is_extern
writable = false
1918 # A local definition of an attribute
1922 redef type MPROPERTY: MAttribute
1923 redef type MPROPDEF: MAttributeDef
1925 init(mclassdef
: MClassDef, mproperty
: MPROPERTY, location
: Location)
1930 # The static type of the attribute
1931 var static_mtype
: nullable MType writable = null
1934 # A local definition of a virtual type
1935 class MVirtualTypeDef
1938 redef type MPROPERTY: MVirtualTypeProp
1939 redef type MPROPDEF: MVirtualTypeDef
1941 init(mclassdef
: MClassDef, mproperty
: MPROPERTY, location
: Location)
1946 # The bound of the virtual type
1947 var bound
: nullable MType writable = null
1954 # * `interface_kind`
1958 # Note this class is basically an enum.
1959 # FIXME: use a real enum once user-defined enums are available
1961 redef var to_s
: String
1963 # Is a constructor required?
1965 private init(s
: String, need_init
: Bool)
1968 self.need_init
= need_init
1971 # Can a class of kind `self` specializes a class of kine `other`?
1972 fun can_specialize
(other
: MClassKind): Bool
1974 if other
== interface_kind
then return true # everybody can specialize interfaces
1975 if self == interface_kind
or self == enum_kind
then
1976 # no other case for interfaces
1978 else if self == extern_kind
then
1979 # only compatible with themselve
1980 return self == other
1981 else if other
== enum_kind
or other
== extern_kind
then
1982 # abstract_kind and concrete_kind are incompatible
1985 # remain only abstract_kind and concrete_kind
1990 fun abstract_kind
: MClassKind do return once
new MClassKind("abstract class", true)
1991 fun concrete_kind
: MClassKind do return once
new MClassKind("class", true)
1992 fun interface_kind
: MClassKind do return once
new MClassKind("interface", false)
1993 fun enum_kind
: MClassKind do return once
new MClassKind("enum", false)
1994 fun extern_kind
: MClassKind do return once
new MClassKind("extern class", false)