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 type `Pointer`, super class to all extern classes
220 fun pointer_type
: MClassType
221 is cached
do return self.get_primitive_class
("Pointer").mclass_type
223 # The primitive type `Bool`
224 fun bool_type
: MClassType
226 var res
= self.bool_type_cache
227 if res
!= null then return res
228 res
= self.get_primitive_class
("Bool").mclass_type
229 self.bool_type_cache
= res
233 private var bool_type_cache
: nullable MClassType
235 # The primitive type `Sys`, the main type of the program, if any
236 fun sys_type
: nullable MClassType
238 var clas
= self.model
.get_mclasses_by_name
("Sys")
239 if clas
== null then return null
240 return get_primitive_class
("Sys").mclass_type
243 fun finalizable_type
: nullable MClassType
245 var clas
= self.model
.get_mclasses_by_name
("Finalizable")
246 if clas
== null then return null
247 return get_primitive_class
("Finalizable").mclass_type
250 # Force to get the primitive class named `name` or abort
251 fun get_primitive_class
(name
: String): MClass
253 var cla
= self.model
.get_mclasses_by_name
(name
)
255 if name
== "Bool" then
256 var c
= new MClass(self, name
, 0, enum_kind
, public_visibility
)
257 var cladef
= new MClassDef(self, c
.mclass_type
, new Location(null, 0,0,0,0), new Array[String])
260 print
("Fatal Error: no primitive class {name}")
263 if cla
.length
!= 1 then
264 var msg
= "Fatal Error: more than one primitive class {name}:"
265 for c
in cla
do msg
+= " {c.full_name}"
272 # Try to get the primitive method named `name` on the type `recv`
273 fun try_get_primitive_method
(name
: String, recv
: MClass): nullable MMethod
275 var props
= self.model
.get_mproperties_by_name
(name
)
276 if props
== null then return null
277 var res
: nullable MMethod = null
278 for mprop
in props
do
279 assert mprop
isa MMethod
280 var intro
= mprop
.intro_mclassdef
281 for mclassdef
in recv
.mclassdefs
do
282 if not self.in_importation
.greaters
.has
(mclassdef
.mmodule
) then continue
283 if not mclassdef
.in_hierarchy
.greaters
.has
(intro
) then continue
286 else if res
!= mprop
then
287 print
("Fatal Error: ambigous property name '{name}'; conflict between {mprop.full_name} and {res.full_name}")
296 private class MClassDefSorter
297 super AbstractSorter[MClassDef]
299 redef fun compare
(a
, b
)
303 if ca
!= cb
then return mmodule
.flatten_mclass_hierarchy
.compare
(ca
, cb
)
304 return mmodule
.model
.mclassdef_hierarchy
.compare
(a
, b
)
308 private class MPropDefSorter
309 super AbstractSorter[MPropDef]
311 redef fun compare
(pa
, pb
)
317 if ca
!= cb
then return mmodule
.flatten_mclass_hierarchy
.compare
(ca
, cb
)
318 return mmodule
.model
.mclassdef_hierarchy
.compare
(a
, b
)
324 # `MClass` are global to the model; it means that a `MClass` is not bound to a
325 # specific `MModule`.
327 # This characteristic helps the reasoning about classes in a program since a
328 # single `MClass` object always denote the same class.
330 # The drawback is that classes (`MClass`) contain almost nothing by themselves.
331 # These do not really have properties nor belong to a hierarchy since the property and the
332 # hierarchy of a class depends of the refinement in the modules.
334 # Most services on classes require the precision of a module, and no one can asks what are
335 # the super-classes of a class nor what are properties of a class without precising what is
336 # the module considered.
338 # For instance, during the typing of a source-file, the module considered is the module of the file.
339 # eg. the question *is the method `foo` exists in the class `Bar`?* must be reformulated into
340 # *is the method `foo` exists in the class `Bar` in the current module?*
342 # During some global analysis, the module considered may be the main module of the program.
346 # The module that introduce the class
347 # While classes are not bound to a specific module,
348 # the introducing module is used for naming an visibility
349 var intro_mmodule
: MModule
351 # The short name of the class
352 # In Nit, the name of a class cannot evolve in refinements
353 redef var name
: String
355 # The canonical name of the class
356 # Example: `"owner::module::MyClass"`
357 fun full_name
: String
359 return "{self.intro_mmodule.full_name}::{name}"
362 # The number of generic formal parameters
363 # 0 if the class is not generic
366 # The kind of the class (interface, abstract class, etc.)
367 # In Nit, the kind of a class cannot evolve in refinements
370 # The visibility of the class
371 # In Nit, the visibility of a class cannot evolve in refinements
372 var visibility
: MVisibility
374 init(intro_mmodule
: MModule, name
: String, arity
: Int, kind
: MClassKind, visibility
: MVisibility)
376 self.intro_mmodule
= intro_mmodule
380 self.visibility
= visibility
381 intro_mmodule
.intro_mclasses
.add
(self)
382 var model
= intro_mmodule
.model
383 model
.mclasses_by_name
.add_one
(name
, self)
384 model
.mclasses
.add
(self)
386 # Create the formal parameter types
388 var mparametertypes
= new Array[MParameterType]
389 for i
in [0..arity
[ do
390 var mparametertype
= new MParameterType(self, i
)
391 mparametertypes
.add
(mparametertype
)
393 var mclass_type
= new MGenericType(self, mparametertypes
)
394 self.mclass_type
= mclass_type
395 self.get_mtype_cache
.add
(mclass_type
)
397 self.mclass_type
= new MClassType(self)
401 redef fun model
do return intro_mmodule
.model
403 # All class definitions (introduction and refinements)
404 var mclassdefs
: Array[MClassDef] = new Array[MClassDef]
407 redef fun to_s
do return self.name
409 # The definition that introduced the class
410 # Warning: the introduction is the first `MClassDef` object associated
411 # to self. If self is just created without having any associated
412 # definition, this method will abort
415 assert has_a_first_definition
: not mclassdefs
.is_empty
416 return mclassdefs
.first
419 # Return the class `self` in the class hierarchy of the module `mmodule`.
421 # SEE: `MModule::flatten_mclass_hierarchy`
422 # REQUIRE: `mmodule.has_mclass(self)`
423 fun in_hierarchy
(mmodule
: MModule): POSetElement[MClass]
425 return mmodule
.flatten_mclass_hierarchy
[self]
428 # The principal static type of the class.
430 # For non-generic class, mclass_type is the only `MClassType` based
433 # For a generic class, the arguments are the formal parameters.
434 # i.e.: for the class Array[E:Object], the `mclass_type` is Array[E].
435 # If you want Array[Object] the see `MClassDef::bound_mtype`
437 # For generic classes, the mclass_type is also the way to get a formal
438 # generic parameter type.
440 # To get other types based on a generic class, see `get_mtype`.
442 # ENSURE: `mclass_type.mclass == self`
443 var mclass_type
: MClassType
445 # Return a generic type based on the class
446 # Is the class is not generic, then the result is `mclass_type`
448 # REQUIRE: `mtype_arguments.length == self.arity`
449 fun get_mtype
(mtype_arguments
: Array[MType]): MClassType
451 assert mtype_arguments
.length
== self.arity
452 if self.arity
== 0 then return self.mclass_type
453 for t
in self.get_mtype_cache
do
454 if t
.arguments
== mtype_arguments
then
458 var res
= new MGenericType(self, mtype_arguments
)
459 self.get_mtype_cache
.add res
463 private var get_mtype_cache
: Array[MGenericType] = new Array[MGenericType]
467 # A definition (an introduction or a refinement) of a class in a module
469 # A `MClassDef` is associated with an explicit (or almost) definition of a
470 # class. Unlike `MClass`, a `MClassDef` is a local definition that belong to
471 # a specific class and a specific module, and contains declarations like super-classes
474 # It is the class definitions that are the backbone of most things in the model:
475 # ClassDefs are defined with regard with other classdefs.
476 # Refinement and specialization are combined to produce a big poset called the `Model::mclassdef_hierarchy`.
478 # Moreover, the extension and the intention of types is defined by looking at the MClassDefs.
482 # The module where the definition is
485 # The associated `MClass`
488 # The bounded type associated to the mclassdef
490 # For a non-generic class, `bound_mtype` and `mclass.mclass_type`
494 # For the classdef Array[E: Object], the bound_mtype is Array[Object].
495 # If you want Array[E], then see `mclass.mclass_type`
497 # ENSURE: `bound_mtype.mclass == self.mclass`
498 var bound_mtype
: MClassType
500 # Name of each formal generic parameter (in order of declaration)
501 var parameter_names
: Array[String]
503 # The origin of the definition
504 var location
: Location
506 # Internal name combining the module and the class
507 # Example: "mymodule#MyClass"
508 redef var to_s
: String
510 init(mmodule
: MModule, bound_mtype
: MClassType, location
: Location, parameter_names
: Array[String])
512 assert bound_mtype
.mclass
.arity
== parameter_names
.length
513 self.bound_mtype
= bound_mtype
514 self.mmodule
= mmodule
515 self.mclass
= bound_mtype
.mclass
516 self.location
= location
517 mmodule
.mclassdefs
.add
(self)
518 mclass
.mclassdefs
.add
(self)
519 self.parameter_names
= parameter_names
520 self.to_s
= "{mmodule}#{mclass}"
523 # Actually the name of the `mclass`
524 redef fun name
do return mclass
.name
526 redef fun model
do return mmodule
.model
528 # All declared super-types
529 # FIXME: quite ugly but not better idea yet
530 var supertypes
: Array[MClassType] = new Array[MClassType]
532 # Register some super-types for the class (ie "super SomeType")
534 # The hierarchy must not already be set
535 # REQUIRE: `self.in_hierarchy == null`
536 fun set_supertypes
(supertypes
: Array[MClassType])
538 assert unique_invocation
: self.in_hierarchy
== null
539 var mmodule
= self.mmodule
540 var model
= mmodule
.model
541 var mtype
= self.bound_mtype
543 for supertype
in supertypes
do
544 self.supertypes
.add
(supertype
)
546 # Register in full_type_specialization_hierarchy
547 model
.full_mtype_specialization_hierarchy
.add_edge
(mtype
, supertype
)
548 # Register in intro_type_specialization_hierarchy
549 if mclass
.intro_mmodule
== mmodule
and supertype
.mclass
.intro_mmodule
== mmodule
then
550 model
.intro_mtype_specialization_hierarchy
.add_edge
(mtype
, supertype
)
556 # Collect the super-types (set by set_supertypes) to build the hierarchy
558 # This function can only invoked once by class
559 # REQUIRE: `self.in_hierarchy == null`
560 # ENSURE: `self.in_hierarchy != null`
563 assert unique_invocation
: self.in_hierarchy
== null
564 var model
= mmodule
.model
565 var res
= model
.mclassdef_hierarchy
.add_node
(self)
566 self.in_hierarchy
= res
567 var mtype
= self.bound_mtype
569 # Here we need to connect the mclassdef to its pairs in the mclassdef_hierarchy
570 # The simpliest way is to attach it to collect_mclassdefs
571 for mclassdef
in mtype
.collect_mclassdefs
(mmodule
) do
572 res
.poset
.add_edge
(self, mclassdef
)
576 # The view of the class definition in `mclassdef_hierarchy`
577 var in_hierarchy
: nullable POSetElement[MClassDef] = null
579 # Is the definition the one that introduced `mclass`?
580 fun is_intro
: Bool do return mclass
.intro
== self
582 # All properties introduced by the classdef
583 var intro_mproperties
: Array[MProperty] = new Array[MProperty]
585 # All property definitions in the class (introductions and redefinitions)
586 var mpropdefs
: Array[MPropDef] = new Array[MPropDef]
589 # A global static type
591 # MType are global to the model; it means that a `MType` is not bound to a
592 # specific `MModule`.
593 # This characteristic helps the reasoning about static types in a program
594 # since a single `MType` object always denote the same type.
596 # However, because a `MType` is global, it does not really have properties
597 # nor have subtypes to a hierarchy since the property and the class hierarchy
598 # depends of a module.
599 # Moreover, virtual types an formal generic parameter types also depends on
600 # a receiver to have sense.
602 # Therefore, most method of the types require a module and an anchor.
603 # The module is used to know what are the classes and the specialization
605 # The anchor is used to know what is the bound of the virtual types and formal
606 # generic parameter types.
608 # MType are not directly usable to get properties. See the `anchor_to` method
609 # and the `MClassType` class.
611 # FIXME: the order of the parameters is not the best. We mus pick on from:
612 # * foo(mmodule, anchor, othertype)
613 # * foo(othertype, anchor, mmodule)
614 # * foo(anchor, mmodule, othertype)
615 # * foo(othertype, mmodule, anchor)
619 redef fun name
do return to_s
621 # Return true if `self` is an subtype of `sup`.
622 # The typing is done using the standard typing policy of Nit.
624 # REQUIRE: `anchor == null implies not self.need_anchor and not sup.need_anchor`
625 # REQUIRE: `anchor != null implies self.can_resolve_for(anchor, null, mmodule) and sup.can_resolve_for(anchor, null, mmodule)`
626 fun is_subtype
(mmodule
: MModule, anchor
: nullable MClassType, sup
: MType): Bool
629 if sub
== sup
then return true
630 if anchor
== null then
631 assert not sub
.need_anchor
632 assert not sup
.need_anchor
634 assert sub
.can_resolve_for
(anchor
, null, mmodule
)
635 assert sup
.can_resolve_for
(anchor
, null, mmodule
)
638 # First, resolve the formal types to a common version in the receiver
639 # The trick here is that fixed formal type will be associed to the bound
640 # And unfixed formal types will be associed to a canonical formal type.
641 if sub
isa MParameterType or sub
isa MVirtualType then
642 assert anchor
!= null
643 sub
= sub
.resolve_for
(anchor
.mclass
.mclass_type
, anchor
, mmodule
, false)
645 if sup
isa MParameterType or sup
isa MVirtualType then
646 assert anchor
!= null
647 sup
= sup
.resolve_for
(anchor
.mclass
.mclass_type
, anchor
, mmodule
, false)
650 # Does `sup` accept null or not?
651 # Discard the nullable marker if it exists
652 var sup_accept_null
= false
653 if sup
isa MNullableType then
654 sup_accept_null
= true
656 else if sup
isa MNullType then
657 sup_accept_null
= true
660 # Can `sub` provide null or not?
661 # Thus we can match with `sup_accept_null`
662 # Also discard the nullable marker if it exists
663 if sub
isa MNullableType then
664 if not sup_accept_null
then return false
666 else if sub
isa MNullType then
667 return sup_accept_null
669 # Now the case of direct null and nullable is over.
671 # A unfixed formal type can only accept itself
672 if sup
isa MParameterType or sup
isa MVirtualType then
676 # If `sub` is a formal type, then it is accepted if its bound is accepted
677 if sub
isa MParameterType or sub
isa MVirtualType then
678 assert anchor
!= null
679 sub
= sub
.anchor_to
(mmodule
, anchor
)
681 # Manage the second layer of null/nullable
682 if sub
isa MNullableType then
683 if not sup_accept_null
then return false
685 else if sub
isa MNullType then
686 return sup_accept_null
690 assert sub
isa MClassType # It is the only remaining type
692 if sup
isa MNullType then
693 # `sup` accepts only null
697 assert sup
isa MClassType # It is the only remaining type
699 # Now both are MClassType, we need to dig
701 if sub
== sup
then return true
703 if anchor
== null then anchor
= sub
# UGLY: any anchor will work
704 var resolved_sub
= sub
.anchor_to
(mmodule
, anchor
)
705 var res
= resolved_sub
.collect_mclasses
(mmodule
).has
(sup
.mclass
)
706 if res
== false then return false
707 if not sup
isa MGenericType then return true
708 var sub2
= sub
.supertype_to
(mmodule
, anchor
, sup
.mclass
)
709 assert sub2
.mclass
== sup
.mclass
710 for i
in [0..sup
.mclass
.arity
[ do
711 var sub_arg
= sub2
.arguments
[i
]
712 var sup_arg
= sup
.arguments
[i
]
713 res
= sub_arg
.is_subtype
(mmodule
, anchor
, sup_arg
)
714 if res
== false then return false
719 # The base class type on which self is based
721 # This base type is used to get property (an internally to perform
722 # unsafe type comparison).
724 # Beware: some types (like null) are not based on a class thus this
727 # Basically, this function transform the virtual types and parameter
728 # types to their bounds.
732 # class B super A end
734 # class Y super X end
742 # Map[T,U] anchor_to H #-> Map[B,Y]
744 # Explanation of the example:
745 # In H, T is set to B, because "H super G[B]", and U is bound to Y,
746 # because "redef type U: Y". Therefore, Map[T, U] is bound to
749 # ENSURE: `not self.need_anchor implies result == self`
750 # ENSURE: `not result.need_anchor`
751 fun anchor_to
(mmodule
: MModule, anchor
: MClassType): MType
753 if not need_anchor
then return self
754 assert not anchor
.need_anchor
755 # Just resolve to the anchor and clear all the virtual types
756 var res
= self.resolve_for
(anchor
, null, mmodule
, true)
757 assert not res
.need_anchor
761 # Does `self` contain a virtual type or a formal generic parameter type?
762 # In order to remove those types, you usually want to use `anchor_to`.
763 fun need_anchor
: Bool do return true
765 # Return the supertype when adapted to a class.
767 # In Nit, for each super-class of a type, there is a equivalent super-type.
771 # class H[V] super G[V, Bool] end
772 # H[Int] supertype_to G #-> G[Int, Bool]
774 # REQUIRE: `super_mclass` is a super-class of `self`
775 # REQUIRE: `self.need_anchor implies anchor != null and self.can_resolve_for(anchor, null, mmodule)`
776 # ENSURE: `result.mclass = super_mclass`
777 fun supertype_to
(mmodule
: MModule, anchor
: nullable MClassType, super_mclass
: MClass): MClassType
779 if super_mclass
.arity
== 0 then return super_mclass
.mclass_type
780 if self isa MClassType and self.mclass
== super_mclass
then return self
782 if self.need_anchor
then
783 assert anchor
!= null
784 resolved_self
= self.anchor_to
(mmodule
, anchor
)
788 var supertypes
= resolved_self
.collect_mtypes
(mmodule
)
789 for supertype
in supertypes
do
790 if supertype
.mclass
== super_mclass
then
791 # FIXME: Here, we stop on the first goal. Should we check others and detect inconsistencies?
792 return supertype
.resolve_for
(self, anchor
, mmodule
, false)
798 # Replace formals generic types in self with resolved values in `mtype`
799 # If `cleanup_virtual` is true, then virtual types are also replaced
802 # This function returns self if `need_anchor` is false.
807 # class H[F] super G[F] end
810 # * Array[E].resolve_for(H[Int]) #-> Array[Int]
811 # * Array[E].resolve_for(G[Z], X[Int]) #-> Array[Z]
813 # Explanation of the example:
814 # * Array[E].need_anchor is true because there is a formal generic parameter type E
815 # * E makes sense for H[Int] because E is a formal parameter of G and H specialize G
816 # * Since "H[F] super G[F]", E is in fact F for H
817 # * More specifically, in H[Int], E is Int
818 # * So, in H[Int], Array[E] is Array[Int]
820 # This function is mainly used to inherit a signature.
821 # Because, unlike `anchor_to`, we do not want a full resolution of
822 # a type but only an adapted version of it.
827 # fun foo(e:E):E is abstract
829 # class B super A[Int] end
831 # The signature on foo is (e: E): E
832 # If we resolve the signature for B, we get (e:Int):Int
837 # fun foo(e:E) is abstract
841 # fun bar do a.foo(x) # <- x is here
844 # The first question is: is foo available on `a`?
846 # The static type of a is `A[Array[F]]`, that is an open type.
847 # in order to find a method `foo`, whe must look at a resolved type.
849 # A[Array[F]].anchor_to(B[nullable Object]) #-> A[Array[nullable Object]]
851 # the method `foo` exists in `A[Array[nullable Object]]`, therefore `foo` exists for `a`.
853 # The next question is: what is the accepted types for `x`?
855 # the signature of `foo` is `foo(e:E)`, thus we must resolve the type E
857 # E.resolve_for(A[Array[F]],B[nullable Object]) #-> Array[F]
859 # The resolution can be done because `E` make sense for the class A (see `can_resolve_for`)
861 # FIXME: the parameter `cleanup_virtual` is just a bad idea, but having
862 # two function instead of one seems also to be a bad idea.
864 # REQUIRE: `can_resolve_for(mtype, anchor, mmodule)`
865 # ENSURE: `not self.need_anchor implies result == self`
866 fun resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule, cleanup_virtual
: Bool): MType is abstract
868 # Can the type be resolved?
870 # In order to resolve open types, the formal types must make sence.
879 # * E.can_resolve_for(A[Int]) #-> true, E make sense in A
880 # * E.can_resolve_for(B[Int]) #-> false, E does not make sense in B
881 # * B[E].can_resolve_for(A[F], B[Object]) #-> true,
882 # B[E] is a red hearing only the E is important,
885 # REQUIRE: `anchor != null implies not anchor.need_anchor`
886 # REQUIRE: `mtype.need_anchor implies anchor != null and mtype.can_resolve_for(anchor, null, mmodule)`
887 # ENSURE: `not self.need_anchor implies result == true`
888 fun can_resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule): Bool is abstract
890 # Return the nullable version of the type
891 # If the type is already nullable then self is returned
892 fun as_nullable
: MType
894 var res
= self.as_nullable_cache
895 if res
!= null then return res
896 res
= new MNullableType(self)
897 self.as_nullable_cache
= res
901 # Return the not nullable version of the type
902 # Is the type is already not nullable, then self is returned.
904 # Note: this just remove the `nullable` notation, but the result can still contains null.
905 # For instance if `self isa MNullType` or self is a a formal type bounded by a nullable type.
906 fun as_notnullable
: MType
911 private var as_nullable_cache
: nullable MType = null
914 # The deph of the type seen as a tree.
921 # Formal types have a depth of 1.
927 # The length of the type seen as a tree.
934 # Formal types have a length of 1.
940 # Compute all the classdefs inherited/imported.
941 # The returned set contains:
942 # * the class definitions from `mmodule` and its imported modules
943 # * the class definitions of this type and its super-types
945 # This function is used mainly internally.
947 # REQUIRE: `not self.need_anchor`
948 fun collect_mclassdefs
(mmodule
: MModule): Set[MClassDef] is abstract
950 # Compute all the super-classes.
951 # This function is used mainly internally.
953 # REQUIRE: `not self.need_anchor`
954 fun collect_mclasses
(mmodule
: MModule): Set[MClass] is abstract
956 # Compute all the declared super-types.
957 # Super-types are returned as declared in the classdefs (verbatim).
958 # This function is used mainly internally.
960 # REQUIRE: `not self.need_anchor`
961 fun collect_mtypes
(mmodule
: MModule): Set[MClassType] is abstract
963 # Is the property in self for a given module
964 # This method does not filter visibility or whatever
966 # REQUIRE: `not self.need_anchor`
967 fun has_mproperty
(mmodule
: MModule, mproperty
: MProperty): Bool
969 assert not self.need_anchor
970 return self.collect_mclassdefs
(mmodule
).has
(mproperty
.intro_mclassdef
)
974 # A type based on a class.
976 # `MClassType` have properties (see `has_mproperty`).
980 # The associated class
983 redef fun model
do return self.mclass
.intro_mmodule
.model
985 private init(mclass
: MClass)
990 # The formal arguments of the type
991 # ENSURE: `result.length == self.mclass.arity`
992 var arguments
: Array[MType] = new Array[MType]
994 redef fun to_s
do return mclass
.to_s
996 redef fun need_anchor
do return false
998 redef fun anchor_to
(mmodule
: MModule, anchor
: MClassType): MClassType
1000 return super.as(MClassType)
1003 redef fun resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule, cleanup_virtual
: Bool): MClassType do return self
1005 redef fun can_resolve_for
(mtype
, anchor
, mmodule
) do return true
1007 redef fun collect_mclassdefs
(mmodule
)
1009 assert not self.need_anchor
1010 var cache
= self.collect_mclassdefs_cache
1011 if not cache
.has_key
(mmodule
) then
1012 self.collect_things
(mmodule
)
1014 return cache
[mmodule
]
1017 redef fun collect_mclasses
(mmodule
)
1019 assert not self.need_anchor
1020 var cache
= self.collect_mclasses_cache
1021 if not cache
.has_key
(mmodule
) then
1022 self.collect_things
(mmodule
)
1024 return cache
[mmodule
]
1027 redef fun collect_mtypes
(mmodule
)
1029 assert not self.need_anchor
1030 var cache
= self.collect_mtypes_cache
1031 if not cache
.has_key
(mmodule
) then
1032 self.collect_things
(mmodule
)
1034 return cache
[mmodule
]
1037 # common implementation for `collect_mclassdefs`, `collect_mclasses`, and `collect_mtypes`.
1038 private fun collect_things
(mmodule
: MModule)
1040 var res
= new HashSet[MClassDef]
1041 var seen
= new HashSet[MClass]
1042 var types
= new HashSet[MClassType]
1043 seen
.add
(self.mclass
)
1044 var todo
= [self.mclass
]
1045 while not todo
.is_empty
do
1046 var mclass
= todo
.pop
1047 #print "process {mclass}"
1048 for mclassdef
in mclass
.mclassdefs
do
1049 if not mmodule
.in_importation
<= mclassdef
.mmodule
then continue
1050 #print " process {mclassdef}"
1052 for supertype
in mclassdef
.supertypes
do
1053 types
.add
(supertype
)
1054 var superclass
= supertype
.mclass
1055 if seen
.has
(superclass
) then continue
1056 #print " add {superclass}"
1057 seen
.add
(superclass
)
1058 todo
.add
(superclass
)
1062 collect_mclassdefs_cache
[mmodule
] = res
1063 collect_mclasses_cache
[mmodule
] = seen
1064 collect_mtypes_cache
[mmodule
] = types
1067 private var collect_mclassdefs_cache
: HashMap[MModule, Set[MClassDef]] = new HashMap[MModule, Set[MClassDef]]
1068 private var collect_mclasses_cache
: HashMap[MModule, Set[MClass]] = new HashMap[MModule, Set[MClass]]
1069 private var collect_mtypes_cache
: HashMap[MModule, Set[MClassType]] = new HashMap[MModule, Set[MClassType]]
1073 # A type based on a generic class.
1074 # A generic type a just a class with additional formal generic arguments.
1078 private init(mclass
: MClass, arguments
: Array[MType])
1081 assert self.mclass
.arity
== arguments
.length
1082 self.arguments
= arguments
1084 self.need_anchor
= false
1085 for t
in arguments
do
1086 if t
.need_anchor
then
1087 self.need_anchor
= true
1092 self.to_s
= "{mclass}[{arguments.join(", ")}]"
1095 # Recursively print the type of the arguments within brackets.
1096 # Example: `"Map[String, List[Int]]"`
1097 redef var to_s
: String
1099 redef var need_anchor
: Bool
1101 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1103 if not need_anchor
then return self
1104 assert can_resolve_for
(mtype
, anchor
, mmodule
)
1105 var types
= new Array[MType]
1106 for t
in arguments
do
1107 types
.add
(t
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
))
1109 return mclass
.get_mtype
(types
)
1112 redef fun can_resolve_for
(mtype
, anchor
, mmodule
)
1114 if not need_anchor
then return true
1115 for t
in arguments
do
1116 if not t
.can_resolve_for
(mtype
, anchor
, mmodule
) then return false
1125 for a
in self.arguments
do
1127 if d
> dmax
then dmax
= d
1135 for a
in self.arguments
do
1142 # A virtual formal type.
1146 # The property associated with the type.
1147 # Its the definitions of this property that determine the bound or the virtual type.
1148 var mproperty
: MProperty
1150 redef fun model
do return self.mproperty
.intro_mclassdef
.mmodule
.model
1152 # Lookup the bound for a given resolved_receiver
1153 # The result may be a other virtual type (or a parameter type)
1155 # The result is returned exactly as declared in the "type" property (verbatim).
1157 # In case of conflict, the method aborts.
1158 fun lookup_bound
(mmodule
: MModule, resolved_receiver
: MType): MType
1160 assert not resolved_receiver
.need_anchor
1161 var props
= self.mproperty
.lookup_definitions
(mmodule
, resolved_receiver
)
1162 if props
.is_empty
then
1164 else if props
.length
== 1 then
1165 return props
.first
.as(MVirtualTypeDef).bound
.as(not null)
1167 var types
= new ArraySet[MType]
1169 types
.add
(p
.as(MVirtualTypeDef).bound
.as(not null))
1171 if types
.length
== 1 then
1177 # Is the virtual type fixed for a given resolved_receiver?
1178 fun is_fixed
(mmodule
: MModule, resolved_receiver
: MType): Bool
1180 assert not resolved_receiver
.need_anchor
1181 var props
= self.mproperty
.lookup_definitions
(mmodule
, resolved_receiver
)
1182 if props
.is_empty
then
1186 if p
.as(MVirtualTypeDef).is_fixed
then return true
1191 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1193 assert can_resolve_for
(mtype
, anchor
, mmodule
)
1194 # self is a virtual type declared (or inherited) in mtype
1195 # The point of the function it to get the bound of the virtual type that make sense for mtype
1196 # But because mtype is maybe a virtual/formal type, we need to get a real receiver first
1197 #print "{class_name}: {self}/{mtype}/{anchor}?"
1198 var resolved_reciever
1199 if mtype
.need_anchor
then
1200 assert anchor
!= null
1201 resolved_reciever
= mtype
.resolve_for
(anchor
, null, mmodule
, true)
1203 resolved_reciever
= mtype
1205 # Now, we can get the bound
1206 var verbatim_bound
= lookup_bound
(mmodule
, resolved_reciever
)
1207 # The bound is exactly as declared in the "type" property, so we must resolve it again
1208 var res
= verbatim_bound
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1209 #print "{class_name}: {self}/{mtype}/{anchor} -> {self}/{resolved_reciever}/{anchor} -> {verbatim_bound}/{mtype}/{anchor} -> {res}"
1211 # What to return here? There is a bunch a special cases:
1212 # If 'cleanup_virtual' we must return the resolved type, since we cannot return self
1213 if cleanup_virtual
then return res
1214 # 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
1215 if resolved_reciever
isa MNullableType then resolved_reciever
= resolved_reciever
.mtype
1216 if resolved_reciever
.as(MClassType).mclass
.kind
== enum_kind
then return res
1217 # 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.
1218 if res
isa MVirtualType then return res
1219 # If we are final, just return the resolution
1220 if is_fixed
(mmodule
, resolved_reciever
) then return res
1221 # 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
1222 if res
isa MClassType and res
.mclass
.kind
== enum_kind
then return res
1223 # TODO: Add 'fixed' virtual type in the specification.
1224 # TODO: What if bound to a MParameterType?
1225 # Note that Nullable types can always be redefined by the non nullable version, so there is no specific case on it.
1227 # If anything apply, then `self' cannot be resolved, so return self
1231 redef fun can_resolve_for
(mtype
, anchor
, mmodule
)
1233 if mtype
.need_anchor
then
1234 assert anchor
!= null
1235 mtype
= mtype
.anchor_to
(mmodule
, anchor
)
1237 return mtype
.has_mproperty
(mmodule
, mproperty
)
1240 redef fun to_s
do return self.mproperty
.to_s
1242 init(mproperty
: MProperty)
1244 self.mproperty
= mproperty
1248 # The type associated the a formal parameter generic type of a class
1250 # Each parameter type is associated to a specific class.
1251 # It's mean that all refinements of a same class "share" the parameter type,
1252 # but that a generic subclass has its on parameter types.
1254 # However, in the sense of the meta-model, a parameter type of a class is
1255 # a valid type in a subclass. The "in the sense of the meta-model" is
1256 # important because, in the Nit language, the programmer cannot refers
1257 # directly to the parameter types of the super-classes.
1261 # fun e: E is abstract
1266 # In the class definition B[F], `F` is a valid type but `E` is not.
1267 # However, `self.e` is a valid method call, and the signature of `e` is
1270 # Note that parameter types are shared among class refinements.
1271 # Therefore parameter only have an internal name (see `to_s` for details).
1272 # TODO: Add a `name_for` to get better messages.
1273 class MParameterType
1276 # The generic class where the parameter belong
1279 redef fun model
do return self.mclass
.intro_mmodule
.model
1281 # The position of the parameter (0 for the first parameter)
1282 # FIXME: is `position` a better name?
1285 # Internal name of the parameter type
1286 # Names of parameter types changes in each class definition
1287 # Therefore, this method return an internal name.
1288 # Example: return "G#1" for the second parameter of the class G
1289 # FIXME: add a way to get the real name in a classdef
1290 redef fun to_s
do return "{mclass}#{rank}"
1292 # Resolve the bound for a given resolved_receiver
1293 # The result may be a other virtual type (or a parameter type)
1294 fun lookup_bound
(mmodule
: MModule, resolved_receiver
: MType): MType
1296 assert not resolved_receiver
.need_anchor
1297 var goalclass
= self.mclass
1298 var supertypes
= resolved_receiver
.collect_mtypes
(mmodule
)
1299 for t
in supertypes
do
1300 if t
.mclass
== goalclass
then
1301 # Yeah! c specialize goalclass with a "super `t'". So the question is what is the argument of f
1302 # FIXME: Here, we stop on the first goal. Should we check others and detect inconsistencies?
1303 var res
= t
.arguments
[self.rank
]
1310 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1312 assert can_resolve_for
(mtype
, anchor
, mmodule
)
1313 #print "{class_name}: {self}/{mtype}/{anchor}?"
1315 if mtype
isa MGenericType and mtype
.mclass
== self.mclass
then
1316 var res
= mtype
.arguments
[self.rank
]
1317 if anchor
!= null and res
.need_anchor
then
1318 # Maybe the result can be resolved more if are bound to a final class
1319 var r2
= res
.anchor_to
(mmodule
, anchor
)
1320 if r2
isa MClassType and r2
.mclass
.kind
== enum_kind
then return r2
1325 # self is a parameter type of mtype (or of a super-class of mtype)
1326 # The point of the function it to get the bound of the virtual type that make sense for mtype
1327 # But because mtype is maybe a virtual/formal type, we need to get a real receiver first
1328 # FIXME: What happend here is far from clear. Thus this part must be validated and clarified
1329 var resolved_receiver
1330 if mtype
.need_anchor
then
1331 assert anchor
!= null
1332 resolved_receiver
= mtype
.resolve_for
(anchor
.mclass
.mclass_type
, anchor
, mmodule
, true)
1334 resolved_receiver
= mtype
1336 if resolved_receiver
isa MNullableType then resolved_receiver
= resolved_receiver
.mtype
1337 if resolved_receiver
isa MParameterType then
1338 assert resolved_receiver
.mclass
== anchor
.mclass
1339 resolved_receiver
= anchor
.arguments
[resolved_receiver
.rank
]
1340 if resolved_receiver
isa MNullableType then resolved_receiver
= resolved_receiver
.mtype
1342 assert resolved_receiver
isa MClassType
1344 # Eh! The parameter is in the current class.
1345 # So we return the corresponding argument, no mater what!
1346 if resolved_receiver
.mclass
== self.mclass
then
1347 var res
= resolved_receiver
.arguments
[self.rank
]
1348 #print "{class_name}: {self}/{mtype}/{anchor} -> direct {res}"
1352 if resolved_receiver
.need_anchor
then
1353 assert anchor
!= null
1354 resolved_receiver
= resolved_receiver
.resolve_for
(anchor
, null, mmodule
, false)
1356 # Now, we can get the bound
1357 var verbatim_bound
= lookup_bound
(mmodule
, resolved_receiver
)
1358 # The bound is exactly as declared in the "type" property, so we must resolve it again
1359 var res
= verbatim_bound
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1361 #print "{class_name}: {self}/{mtype}/{anchor} -> indirect {res}"
1366 redef fun can_resolve_for
(mtype
, anchor
, mmodule
)
1368 if mtype
.need_anchor
then
1369 assert anchor
!= null
1370 mtype
= mtype
.anchor_to
(mmodule
, anchor
)
1372 return mtype
.collect_mclassdefs
(mmodule
).has
(mclass
.intro
)
1375 init(mclass
: MClass, rank
: Int)
1377 self.mclass
= mclass
1382 # A type prefixed with "nullable"
1386 # The base type of the nullable type
1389 redef fun model
do return self.mtype
.model
1394 self.to_s
= "nullable {mtype}"
1397 redef var to_s
: String
1399 redef fun need_anchor
do return mtype
.need_anchor
1400 redef fun as_nullable
do return self
1401 redef fun as_notnullable
do return mtype
1402 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1404 var res
= self.mtype
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1405 return res
.as_nullable
1408 redef fun can_resolve_for
(mtype
, anchor
, mmodule
)
1410 return self.mtype
.can_resolve_for
(mtype
, anchor
, mmodule
)
1413 redef fun depth
do return self.mtype
.depth
1415 redef fun length
do return self.mtype
.length
1417 redef fun collect_mclassdefs
(mmodule
)
1419 assert not self.need_anchor
1420 return self.mtype
.collect_mclassdefs
(mmodule
)
1423 redef fun collect_mclasses
(mmodule
)
1425 assert not self.need_anchor
1426 return self.mtype
.collect_mclasses
(mmodule
)
1429 redef fun collect_mtypes
(mmodule
)
1431 assert not self.need_anchor
1432 return self.mtype
.collect_mtypes
(mmodule
)
1436 # The type of the only value null
1438 # The is only one null type per model, see `MModel::null_type`.
1441 redef var model
: Model
1442 protected init(model
: Model)
1446 redef fun to_s
do return "null"
1447 redef fun as_nullable
do return self
1448 redef fun need_anchor
do return false
1449 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
) do return self
1450 redef fun can_resolve_for
(mtype
, anchor
, mmodule
) do return true
1452 redef fun collect_mclassdefs
(mmodule
) do return new HashSet[MClassDef]
1454 redef fun collect_mclasses
(mmodule
) do return new HashSet[MClass]
1456 redef fun collect_mtypes
(mmodule
) do return new HashSet[MClassType]
1459 # A signature of a method
1463 # The each parameter (in order)
1464 var mparameters
: Array[MParameter]
1466 # The return type (null for a procedure)
1467 var return_mtype
: nullable MType
1472 var t
= self.return_mtype
1473 if t
!= null then dmax
= t
.depth
1474 for p
in mparameters
do
1475 var d
= p
.mtype
.depth
1476 if d
> dmax
then dmax
= d
1484 var t
= self.return_mtype
1485 if t
!= null then res
+= t
.length
1486 for p
in mparameters
do
1487 res
+= p
.mtype
.length
1492 # REQUIRE: 1 <= mparameters.count p -> p.is_vararg
1493 init(mparameters
: Array[MParameter], return_mtype
: nullable MType)
1495 var vararg_rank
= -1
1496 for i
in [0..mparameters
.length
[ do
1497 var parameter
= mparameters
[i
]
1498 if parameter
.is_vararg
then
1499 assert vararg_rank
== -1
1503 self.mparameters
= mparameters
1504 self.return_mtype
= return_mtype
1505 self.vararg_rank
= vararg_rank
1508 # The rank of the ellipsis (`...`) for vararg (starting from 0).
1509 # value is -1 if there is no vararg.
1510 # Example: for "(a: Int, b: Bool..., c: Char)" #-> vararg_rank=1
1511 var vararg_rank
: Int
1513 # The number or parameters
1514 fun arity
: Int do return mparameters
.length
1518 var b
= new FlatBuffer
1519 if not mparameters
.is_empty
then
1521 for i
in [0..mparameters
.length
[ do
1522 var mparameter
= mparameters
[i
]
1523 if i
> 0 then b
.append
(", ")
1524 b
.append
(mparameter
.name
)
1526 b
.append
(mparameter
.mtype
.to_s
)
1527 if mparameter
.is_vararg
then
1533 var ret
= self.return_mtype
1541 redef fun resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule, cleanup_virtual
: Bool): MSignature
1543 var params
= new Array[MParameter]
1544 for p
in self.mparameters
do
1545 params
.add
(p
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
))
1547 var ret
= self.return_mtype
1549 ret
= ret
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1551 var res
= new MSignature(params
, ret
)
1556 # A parameter in a signature
1560 # The name of the parameter
1561 redef var name
: String
1563 # The static type of the parameter
1566 # Is the parameter a vararg?
1569 init(name
: String, mtype
: MType, is_vararg
: Bool) do
1572 self.is_vararg
= is_vararg
1578 return "{name}: {mtype}..."
1580 return "{name}: {mtype}"
1584 fun resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule, cleanup_virtual
: Bool): MParameter
1586 if not self.mtype
.need_anchor
then return self
1587 var newtype
= self.mtype
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1588 var res
= new MParameter(self.name
, newtype
, self.is_vararg
)
1592 redef fun model
do return mtype
.model
1595 # A service (global property) that generalize method, attribute, etc.
1597 # `MProperty` are global to the model; it means that a `MProperty` is not bound
1598 # to a specific `MModule` nor a specific `MClass`.
1600 # A MProperty gather definitions (see `mpropdefs`) ; one for the introduction
1601 # and the other in subclasses and in refinements.
1603 # A `MProperty` is used to denotes services in polymorphic way (ie. independent
1604 # of any dynamic type).
1605 # For instance, a call site "x.foo" is associated to a `MProperty`.
1606 abstract class MProperty
1609 # The associated MPropDef subclass.
1610 # The two specialization hierarchy are symmetric.
1611 type MPROPDEF: MPropDef
1613 # The classdef that introduce the property
1614 # While a property is not bound to a specific module, or class,
1615 # the introducing mclassdef is used for naming and visibility
1616 var intro_mclassdef
: MClassDef
1618 # The (short) name of the property
1619 redef var name
: String
1621 # The canonical name of the property
1622 # Example: "owner::my_module::MyClass::my_method"
1623 fun full_name
: String
1625 return "{self.intro_mclassdef.mmodule.full_name}::{self.intro_mclassdef.mclass.name}::{name}"
1628 # The visibility of the property
1629 var visibility
: MVisibility
1631 init(intro_mclassdef
: MClassDef, name
: String, visibility
: MVisibility)
1633 self.intro_mclassdef
= intro_mclassdef
1635 self.visibility
= visibility
1636 intro_mclassdef
.intro_mproperties
.add
(self)
1637 var model
= intro_mclassdef
.mmodule
.model
1638 model
.mproperties_by_name
.add_one
(name
, self)
1639 model
.mproperties
.add
(self)
1642 # All definitions of the property.
1643 # The first is the introduction,
1644 # The other are redefinitions (in refinements and in subclasses)
1645 var mpropdefs
: Array[MPROPDEF] = new Array[MPROPDEF]
1647 # The definition that introduced the property
1648 # Warning: the introduction is the first `MPropDef` object
1649 # associated to self. If self is just created without having any
1650 # associated definition, this method will abort
1651 fun intro
: MPROPDEF do return mpropdefs
.first
1653 redef fun model
do return intro
.model
1656 redef fun to_s
do return name
1658 # Return the most specific property definitions defined or inherited by a type.
1659 # The selection knows that refinement is stronger than specialization;
1660 # however, in case of conflict more than one property are returned.
1661 # If mtype does not know mproperty then an empty array is returned.
1663 # If you want the really most specific property, then look at `lookup_first_definition`
1664 fun lookup_definitions
(mmodule
: MModule, mtype
: MType): Array[MPROPDEF]
1666 assert not mtype
.need_anchor
1667 mtype
= mtype
.as_notnullable
1669 var cache
= self.lookup_definitions_cache
[mmodule
, mtype
]
1670 if cache
!= null then return cache
1672 #print "select prop {mproperty} for {mtype} in {self}"
1673 # First, select all candidates
1674 var candidates
= new Array[MPROPDEF]
1675 for mpropdef
in self.mpropdefs
do
1676 # If the definition is not imported by the module, then skip
1677 if not mmodule
.in_importation
<= mpropdef
.mclassdef
.mmodule
then continue
1678 # If the definition is not inherited by the type, then skip
1679 if not mtype
.is_subtype
(mmodule
, null, mpropdef
.mclassdef
.bound_mtype
) then continue
1681 candidates
.add
(mpropdef
)
1683 # Fast track for only one candidate
1684 if candidates
.length
<= 1 then
1685 self.lookup_definitions_cache
[mmodule
, mtype
] = candidates
1689 # Second, filter the most specific ones
1690 return select_most_specific
(mmodule
, candidates
)
1693 private var lookup_definitions_cache
: HashMap2[MModule, MType, Array[MPROPDEF]] = new HashMap2[MModule, MType, Array[MPROPDEF]]
1695 # Return the most specific property definitions inherited by a type.
1696 # The selection knows that refinement is stronger than specialization;
1697 # however, in case of conflict more than one property are returned.
1698 # If mtype does not know mproperty then an empty array is returned.
1700 # If you want the really most specific property, then look at `lookup_next_definition`
1702 # FIXME: Move to `MPropDef`?
1703 fun lookup_super_definitions
(mmodule
: MModule, mtype
: MType): Array[MPROPDEF]
1705 assert not mtype
.need_anchor
1706 mtype
= mtype
.as_notnullable
1708 # First, select all candidates
1709 var candidates
= new Array[MPROPDEF]
1710 for mpropdef
in self.mpropdefs
do
1711 # If the definition is not imported by the module, then skip
1712 if not mmodule
.in_importation
<= mpropdef
.mclassdef
.mmodule
then continue
1713 # If the definition is not inherited by the type, then skip
1714 if not mtype
.is_subtype
(mmodule
, null, mpropdef
.mclassdef
.bound_mtype
) then continue
1715 # If the definition is defined by the type, then skip (we want the super, so e skip the current)
1716 if mtype
== mpropdef
.mclassdef
.bound_mtype
and mmodule
== mpropdef
.mclassdef
.mmodule
then continue
1718 candidates
.add
(mpropdef
)
1720 # Fast track for only one candidate
1721 if candidates
.length
<= 1 then return candidates
1723 # Second, filter the most specific ones
1724 return select_most_specific
(mmodule
, candidates
)
1727 # Return an array containing olny the most specific property definitions
1728 # This is an helper function for `lookup_definitions` and `lookup_super_definitions`
1729 private fun select_most_specific
(mmodule
: MModule, candidates
: Array[MPROPDEF]): Array[MPROPDEF]
1731 var res
= new Array[MPROPDEF]
1732 for pd1
in candidates
do
1733 var cd1
= pd1
.mclassdef
1736 for pd2
in candidates
do
1737 if pd2
== pd1
then continue # do not compare with self!
1738 var cd2
= pd2
.mclassdef
1740 if c2
.mclass_type
== c1
.mclass_type
then
1741 if cd2
.mmodule
.in_importation
< cd1
.mmodule
then
1742 # cd2 refines cd1; therefore we skip pd1
1746 else if cd2
.bound_mtype
.is_subtype
(mmodule
, null, cd1
.bound_mtype
) and cd2
.bound_mtype
!= cd1
.bound_mtype
then
1747 # cd2 < cd1; therefore we skip pd1
1756 if res
.is_empty
then
1757 print
"All lost! {candidates.join(", ")}"
1758 # FIXME: should be abort!
1763 # Return the most specific definition in the linearization of `mtype`.
1765 # If you want to know the next properties in the linearization,
1766 # look at `MPropDef::lookup_next_definition`.
1768 # FIXME: the linearisation is still unspecified
1770 # REQUIRE: `not mtype.need_anchor`
1771 # REQUIRE: `mtype.has_mproperty(mmodule, self)`
1772 fun lookup_first_definition
(mmodule
: MModule, mtype
: MType): MPROPDEF
1774 assert mtype
.has_mproperty
(mmodule
, self)
1775 return lookup_all_definitions
(mmodule
, mtype
).first
1778 # Return all definitions in a linearisation order
1779 # Most speficic first, most general last
1780 fun lookup_all_definitions
(mmodule
: MModule, mtype
: MType): Array[MPROPDEF]
1782 assert not mtype
.need_anchor
1783 mtype
= mtype
.as_notnullable
1785 var cache
= self.lookup_all_definitions_cache
[mmodule
, mtype
]
1786 if cache
!= null then return cache
1788 #print "select prop {mproperty} for {mtype} in {self}"
1789 # First, select all candidates
1790 var candidates
= new Array[MPROPDEF]
1791 for mpropdef
in self.mpropdefs
do
1792 # If the definition is not imported by the module, then skip
1793 if not mmodule
.in_importation
<= mpropdef
.mclassdef
.mmodule
then continue
1794 # If the definition is not inherited by the type, then skip
1795 if not mtype
.is_subtype
(mmodule
, null, mpropdef
.mclassdef
.bound_mtype
) then continue
1797 candidates
.add
(mpropdef
)
1799 # Fast track for only one candidate
1800 if candidates
.length
<= 1 then
1801 self.lookup_all_definitions_cache
[mmodule
, mtype
] = candidates
1805 mmodule
.linearize_mpropdefs
(candidates
)
1806 candidates
= candidates
.reversed
1807 self.lookup_all_definitions_cache
[mmodule
, mtype
] = candidates
1811 private var lookup_all_definitions_cache
: HashMap2[MModule, MType, Array[MPROPDEF]] = new HashMap2[MModule, MType, Array[MPROPDEF]]
1818 redef type MPROPDEF: MMethodDef
1820 init(intro_mclassdef
: MClassDef, name
: String, visibility
: MVisibility)
1825 # Is the property defined at the top_level of the module?
1826 # Currently such a property are stored in `Object`
1827 var is_toplevel
: Bool writable = false
1829 # Is the property a constructor?
1830 # Warning, this property can be inherited by subclasses with or without being a constructor
1831 # therefore, you should use `is_init_for` the verify if the property is a legal constructor for a given class
1832 var is_init
: Bool writable = false
1834 # The constructor is a (the) root init with empty signature but a set of initializers
1835 var is_root_init
: Bool writable = false
1837 # The the property a 'new' contructor?
1838 var is_new
: Bool writable = false
1840 # Is the property a legal constructor for a given class?
1841 # As usual, visibility is not considered.
1842 # FIXME not implemented
1843 fun is_init_for
(mclass
: MClass): Bool
1849 # A global attribute
1853 redef type MPROPDEF: MAttributeDef
1855 init(intro_mclassdef
: MClassDef, name
: String, visibility
: MVisibility)
1861 # A global virtual type
1862 class MVirtualTypeProp
1865 redef type MPROPDEF: MVirtualTypeDef
1867 init(intro_mclassdef
: MClassDef, name
: String, visibility
: MVisibility)
1872 # The formal type associated to the virtual type property
1873 var mvirtualtype
: MVirtualType = new MVirtualType(self)
1876 # A definition of a property (local property)
1878 # Unlike `MProperty`, a `MPropDef` is a local definition that belong to a
1879 # specific class definition (which belong to a specific module)
1880 abstract class MPropDef
1883 # The associated `MProperty` subclass.
1884 # the two specialization hierarchy are symmetric
1885 type MPROPERTY: MProperty
1888 type MPROPDEF: MPropDef
1890 # The origin of the definition
1891 var location
: Location
1893 # The class definition where the property definition is
1894 var mclassdef
: MClassDef
1896 # The associated global property
1897 var mproperty
: MPROPERTY
1899 init(mclassdef
: MClassDef, mproperty
: MPROPERTY, location
: Location)
1901 self.mclassdef
= mclassdef
1902 self.mproperty
= mproperty
1903 self.location
= location
1904 mclassdef
.mpropdefs
.add
(self)
1905 mproperty
.mpropdefs
.add
(self)
1906 self.to_s
= "{mclassdef}#{mproperty}"
1909 # Actually the name of the `mproperty`
1910 redef fun name
do return mproperty
.name
1912 redef fun model
do return mclassdef
.model
1914 # Internal name combining the module, the class and the property
1915 # Example: "mymodule#MyClass#mymethod"
1916 redef var to_s
: String
1918 # Is self the definition that introduce the property?
1919 fun is_intro
: Bool do return mproperty
.intro
== self
1921 # Return the next definition in linearization of `mtype`.
1923 # This method is used to determine what method is called by a super.
1925 # REQUIRE: `not mtype.need_anchor`
1926 fun lookup_next_definition
(mmodule
: MModule, mtype
: MType): MPROPDEF
1928 assert not mtype
.need_anchor
1930 var mpropdefs
= self.mproperty
.lookup_all_definitions
(mmodule
, mtype
)
1931 var i
= mpropdefs
.iterator
1932 while i
.is_ok
and i
.item
!= self do i
.next
1933 assert has_property
: i
.is_ok
1935 assert has_next_property
: i
.is_ok
1940 # A local definition of a method
1944 redef type MPROPERTY: MMethod
1945 redef type MPROPDEF: MMethodDef
1947 init(mclassdef
: MClassDef, mproperty
: MPROPERTY, location
: Location)
1952 # The signature attached to the property definition
1953 var msignature
: nullable MSignature writable = null
1955 # The signature attached to the `new` call on a root-init
1956 # This is a concatenation of the signatures of the initializers
1958 # REQUIRE `mproperty.is_root_init == (new_msignature != null)`
1959 var new_msignature
: nullable MSignature writable = null
1961 # List of initialisers to call in root-inits
1963 # They could be setters or attributes
1965 # REQUIRE `mproperty.is_root_init == (new_msignature != null)`
1966 var initializers
= new Array[MProperty]
1968 # Is the method definition abstract?
1969 var is_abstract
: Bool writable = false
1971 # Is the method definition intern?
1972 var is_intern
writable = false
1974 # Is the method definition extern?
1975 var is_extern
writable = false
1978 # A local definition of an attribute
1982 redef type MPROPERTY: MAttribute
1983 redef type MPROPDEF: MAttributeDef
1985 init(mclassdef
: MClassDef, mproperty
: MPROPERTY, location
: Location)
1990 # The static type of the attribute
1991 var static_mtype
: nullable MType writable = null
1994 # A local definition of a virtual type
1995 class MVirtualTypeDef
1998 redef type MPROPERTY: MVirtualTypeProp
1999 redef type MPROPDEF: MVirtualTypeDef
2001 init(mclassdef
: MClassDef, mproperty
: MPROPERTY, location
: Location)
2006 # The bound of the virtual type
2007 var bound
: nullable MType writable = null
2009 # Is the bound fixed?
2010 var is_fixed
writable = false
2017 # * `interface_kind`
2021 # Note this class is basically an enum.
2022 # FIXME: use a real enum once user-defined enums are available
2024 redef var to_s
: String
2026 # Is a constructor required?
2028 private init(s
: String, need_init
: Bool)
2031 self.need_init
= need_init
2034 # Can a class of kind `self` specializes a class of kine `other`?
2035 fun can_specialize
(other
: MClassKind): Bool
2037 if other
== interface_kind
then return true # everybody can specialize interfaces
2038 if self == interface_kind
or self == enum_kind
then
2039 # no other case for interfaces
2041 else if self == extern_kind
then
2042 # only compatible with themselve
2043 return self == other
2044 else if other
== enum_kind
or other
== extern_kind
then
2045 # abstract_kind and concrete_kind are incompatible
2048 # remain only abstract_kind and concrete_kind
2053 fun abstract_kind
: MClassKind do return once
new MClassKind("abstract class", true)
2054 fun concrete_kind
: MClassKind do return once
new MClassKind("class", true)
2055 fun interface_kind
: MClassKind do return once
new MClassKind("interface", false)
2056 fun enum_kind
: MClassKind do return once
new MClassKind("enum", false)
2057 fun extern_kind
: MClassKind do return once
new MClassKind("extern class", false)