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 # Object model of the Nit language
19 # This module define the entities of the Nit meta-model like modules,
20 # classes, types and properties
22 # It also provide an API to build and query models.
24 # All model classes starts with the M letter (MModule, MClass, etc.)
28 # TODO: liearization, closures, extern stuff
29 # FIXME: better handling of the types
35 private import more_collections
39 var mclasses
: Array[MClass] = new Array[MClass]
41 # All known properties
42 var mproperties
: Array[MProperty] = new Array[MProperty]
44 # Hierarchy of class definition.
46 # Each classdef is associated with its super-classdefs in regard to
47 # its module of definition.
48 var mclassdef_hierarchy
: POSet[MClassDef] = new POSet[MClassDef]
50 # Class-type hierarchy restricted to the introduction.
52 # The idea is that what is true on introduction is always true whatever
53 # the module considered.
54 # Therefore, this hierarchy is used for a fast positive subtype check.
56 # This poset will evolve in a monotonous way:
57 # * Two non connected nodes will remain unconnected
58 # * New nodes can appear with new edges
59 private var intro_mtype_specialization_hierarchy
: POSet[MClassType] = new POSet[MClassType]
61 # Global overlapped class-type hierarchy.
62 # The hierarchy when all modules are combined.
63 # Therefore, this hierarchy is used for a fast negative subtype check.
65 # This poset will evolve in an anarchic way. Loops can even be created.
67 # FIXME decide what to do on loops
68 private var full_mtype_specialization_hierarchy
: POSet[MClassType] = new POSet[MClassType]
70 # Collections of classes grouped by their short name
71 private var mclasses_by_name
: MultiHashMap[String, MClass] = new MultiHashMap[String, MClass]
73 # Return all class named `name'.
75 # If such a class does not exist, null is returned
76 # (instead of an empty array)
78 # Visibility or modules are not considered
79 fun get_mclasses_by_name
(name
: String): nullable Array[MClass]
81 if mclasses_by_name
.has_key
(name
) then
82 return mclasses_by_name
[name
]
88 # Collections of properties grouped by their short name
89 private var mproperties_by_name
: MultiHashMap[String, MProperty] = new MultiHashMap[String, MProperty]
91 # Return all properties named `name'.
93 # If such a property does not exist, null is returned
94 # (instead of an empty array)
96 # Visibility or modules are not considered
97 fun get_mproperties_by_name
(name
: String): nullable Array[MProperty]
99 if not mproperties_by_name
.has_key
(name
) then
102 return mproperties_by_name
[name
]
107 var null_type
: MNullType = new MNullType(self)
111 # All the classes introduced in the module
112 var intro_mclasses
: Array[MClass] = new Array[MClass]
114 # All the class definitions of the module
115 # (introduction and refinement)
116 var mclassdefs
: Array[MClassDef] = new Array[MClassDef]
118 # Does the current module has a given class `mclass'?
119 # Return true if the mmodule introduces, refines or imports a class.
120 # Visibility is not considered.
121 fun has_mclass
(mclass
: MClass): Bool
123 return self.in_importation
<= mclass
.intro_mmodule
126 # Full hierarchy of introduced ans imported classes.
128 # Create a new hierarchy got by flattening the classes for the module
129 # and its imported modules.
130 # Visibility is not considered.
132 # Note: this function is expensive and is usually used for the main
133 # module of a program only. Do not use it to do you own subtype
135 fun flatten_mclass_hierarchy
: POSet[MClass]
137 var res
= self.flatten_mclass_hierarchy_cache
138 if res
!= null then return res
139 res
= new POSet[MClass]
140 for m
in self.in_importation
.greaters
do
141 for cd
in m
.mclassdefs
do
144 for s
in cd
.supertypes
do
145 res
.add_edge
(c
, s
.mclass
)
149 self.flatten_mclass_hierarchy_cache
= res
153 # Sort a given array of classes using the linerarization order of the module
154 # The most general is first, the most specific is last
155 fun linearize_mclasses
(mclasses
: Array[MClass])
157 self.flatten_mclass_hierarchy
.sort
(mclasses
)
160 # Sort a given array of class definitions using the linerarization order of the module
161 # the refinement link is stronger than the specialisation link
162 # The most general is first, the most specific is last
163 fun linearize_mclassdefs
(mclassdefs
: Array[MClassDef])
165 var sorter
= new MClassDefSorter(self)
166 sorter
.sort
(mclassdefs
)
169 # Sort a given array of property definitions using the linerarization order of the module
170 # the refinement link is stronger than the specialisation link
171 # The most general is first, the most specific is last
172 fun linearize_mpropdefs
(mpropdefs
: Array[MPropDef])
174 var sorter
= new MPropDefSorter(self)
175 sorter
.sort
(mpropdefs
)
178 private var flatten_mclass_hierarchy_cache
: nullable POSet[MClass] = null
180 # The primitive type Object, the root of the class hierarchy
181 fun object_type
: MClassType
183 var res
= self.object_type_cache
184 if res
!= null then return res
185 res
= self.get_primitive_class
("Object").mclass_type
186 self.object_type_cache
= res
190 private var object_type_cache
: nullable MClassType
192 # The primitive type Bool
193 fun bool_type
: MClassType
195 var res
= self.bool_type_cache
196 if res
!= null then return res
197 res
= self.get_primitive_class
("Bool").mclass_type
198 self.bool_type_cache
= res
202 private var bool_type_cache
: nullable MClassType
204 # The primitive type Sys, the main type of the program, if any
205 fun sys_type
: nullable MClassType
207 var clas
= self.model
.get_mclasses_by_name
("Sys")
208 if clas
== null then return null
209 return get_primitive_class
("Sys").mclass_type
212 # Force to get the primitive class named `name' or abort
213 fun get_primitive_class
(name
: String): MClass
215 var cla
= self.model
.get_mclasses_by_name
(name
)
217 if name
== "Bool" then
218 var c
= new MClass(self, name
, 0, enum_kind
, public_visibility
)
219 var cladef
= new MClassDef(self, c
.mclass_type
, new Location(null, 0,0,0,0), new Array[String])
222 print
("Fatal Error: no primitive class {name}")
225 assert cla
.length
== 1 else print cla
.join
(", ")
229 # Try to get the primitive method named `name' on the type `recv'
230 fun try_get_primitive_method
(name
: String, recv
: MType): nullable MMethod
232 var props
= self.model
.get_mproperties_by_name
(name
)
233 if props
== null then return null
234 var res
: nullable MMethod = null
235 for mprop
in props
do
236 assert mprop
isa MMethod
237 if not recv
.has_mproperty
(self, mprop
) then continue
241 print
("Fatal Error: ambigous property name '{name}'; conflict between {mprop.full_name} and {res.full_name}")
249 private class MClassDefSorter
250 super AbstractSorter[MClassDef]
252 redef fun compare
(a
, b
)
256 if ca
!= cb
then return mmodule
.flatten_mclass_hierarchy
.compare
(ca
, cb
)
257 return mmodule
.model
.mclassdef_hierarchy
.compare
(a
, b
)
261 private class MPropDefSorter
262 super AbstractSorter[MPropDef]
264 redef fun compare
(pa
, pb
)
270 if ca
!= cb
then return mmodule
.flatten_mclass_hierarchy
.compare
(ca
, cb
)
271 return mmodule
.model
.mclassdef_hierarchy
.compare
(a
, b
)
277 # MClass are global to the model; it means that a MClass is not bound to a
278 # specific `MModule`.
280 # This characteristic helps the reasoning about classes in a program since a
281 # single MClass object always denote the same class.
282 # However, because a MClass is global, it does not really have properties nor
283 # belong to a hierarchy since the property and the
284 # hierarchy of a class depends of a module.
286 # The module that introduce the class
287 # While classes are not bound to a specific module,
288 # the introducing module is used for naming an visibility
289 var intro_mmodule
: MModule
291 # The short name of the class
292 # In Nit, the name of a class cannot evolve in refinements
295 # The canonical name of the class
296 # Example: "owner::module::MyClass"
297 fun full_name
: String
299 return "{self.intro_mmodule.full_name}::{name}"
302 # The number of generic formal parameters
303 # 0 if the class is not generic
306 # The kind of the class (interface, abstract class, etc.)
307 # In Nit, the kind of a class cannot evolve in refinements
310 # The visibility of the class
311 # In Nit, the visibility of a class cannot evolve in refinements
312 var visibility
: MVisibility
314 init(intro_mmodule
: MModule, name
: String, arity
: Int, kind
: MClassKind, visibility
: MVisibility)
316 self.intro_mmodule
= intro_mmodule
320 self.visibility
= visibility
321 intro_mmodule
.intro_mclasses
.add
(self)
322 var model
= intro_mmodule
.model
323 model
.mclasses_by_name
.add_one
(name
, self)
324 model
.mclasses
.add
(self)
326 # Create the formal parameter types
328 var mparametertypes
= new Array[MParameterType]
329 for i
in [0..arity
[ do
330 var mparametertype
= new MParameterType(self, i
)
331 mparametertypes
.add
(mparametertype
)
333 var mclass_type
= new MGenericType(self, mparametertypes
)
334 self.mclass_type
= mclass_type
335 self.get_mtype_cache
.add
(mclass_type
)
337 self.mclass_type
= new MClassType(self)
341 # All class definitions (introduction and refinements)
342 var mclassdefs
: Array[MClassDef] = new Array[MClassDef]
345 redef fun to_s
do return self.name
347 # The definition that introduced the class
348 # Warning: the introduction is the first `MClassDef' object associated
349 # to self. If self is just created without having any associated
350 # definition, this method will abort
353 assert has_a_first_definition
: not mclassdefs
.is_empty
354 return mclassdefs
.first
357 # Return the class `self' in the class hierarchy of the module `mmodule'.
359 # SEE: MModule::flatten_mclass_hierarchy
360 # REQUIRE: mmodule.has_mclass(self)
361 fun in_hierarchy
(mmodule
: MModule): POSetElement[MClass]
363 return mmodule
.flatten_mclass_hierarchy
[self]
366 # The principal static type of the class.
368 # For non-generic class, mclass_type is the only MClassType based
371 # For a generic class, the arguments are the formal parameters.
372 # i.e.: for the class `Array[E:Object]', the mtype is Array[E].
373 # If you want `Array[Object]' the see `MClassDef::bound_mtype'
375 # For generic classes, the mclass_type is also the way to get a formal
376 # generic parameter type.
378 # To get other types based on a generic class, see `get_mtype'.
380 # ENSURE: mclass_type.mclass == self
381 var mclass_type
: MClassType
383 # Return a generic type based on the class
384 # Is the class is not generic, then the result is `mclass_type'
386 # REQUIRE: type_arguments.length == self.arity
387 fun get_mtype
(mtype_arguments
: Array[MType]): MClassType
389 assert mtype_arguments
.length
== self.arity
390 if self.arity
== 0 then return self.mclass_type
391 for t
in self.get_mtype_cache
do
392 if t
.arguments
== mtype_arguments
then
396 var res
= new MGenericType(self, mtype_arguments
)
397 self.get_mtype_cache
.add res
401 private var get_mtype_cache
: Array[MGenericType] = new Array[MGenericType]
405 # A definition (an introduction or a refinement) of a class in a module
407 # A MClassDef is associated with an explicit (or almost) definition of a
408 # class. Unlike MClass, a MClassDef is a local definition that belong to
411 # The module where the definition is
414 # The associated MClass
417 # The bounded type associated to the mclassdef
419 # For a non-generic class, `bound_mtype' and `mclass.mclass_type'
423 # For the classdef Array[E: Object], the bound_mtype is Array[Object].
424 # If you want Array[E], then see `mclass.mclass_type'
426 # ENSURE: bound_mtype.mclass = self.mclass
427 var bound_mtype
: MClassType
429 # Name of each formal generic parameter (in order of declaration)
430 var parameter_names
: Array[String]
432 # The origin of the definition
433 var location
: Location
435 # Internal name combining the module and the class
436 # Example: "mymodule#MyClass"
437 redef var to_s
: String
439 init(mmodule
: MModule, bound_mtype
: MClassType, location
: Location, parameter_names
: Array[String])
441 assert bound_mtype
.mclass
.arity
== parameter_names
.length
442 self.bound_mtype
= bound_mtype
443 self.mmodule
= mmodule
444 self.mclass
= bound_mtype
.mclass
445 self.location
= location
446 mmodule
.mclassdefs
.add
(self)
447 mclass
.mclassdefs
.add
(self)
448 self.parameter_names
= parameter_names
449 self.to_s
= "{mmodule}#{mclass}"
452 # All declared super-types
453 # FIXME: quite ugly but not better idea yet
454 var supertypes
: Array[MClassType] = new Array[MClassType]
456 # Register some super-types for the class (ie "super SomeType")
458 # The hierarchy must not already be set
459 # REQUIRE: self.in_hierarchy == null
460 fun set_supertypes
(supertypes
: Array[MClassType])
462 assert unique_invocation
: self.in_hierarchy
== null
463 var mmodule
= self.mmodule
464 var model
= mmodule
.model
465 var mtype
= self.bound_mtype
467 for supertype
in supertypes
do
468 self.supertypes
.add
(supertype
)
470 # Register in full_type_specialization_hierarchy
471 model
.full_mtype_specialization_hierarchy
.add_edge
(mtype
, supertype
)
472 # Register in intro_type_specialization_hierarchy
473 if mclass
.intro_mmodule
== mmodule
and supertype
.mclass
.intro_mmodule
== mmodule
then
474 model
.intro_mtype_specialization_hierarchy
.add_edge
(mtype
, supertype
)
480 # Collect the super-types (set by set_supertypes) to build the hierarchy
482 # This function can only invoked once by class
483 # REQUIRE: self.in_hierarchy == null
484 # ENSURE: self.in_hierarchy != null
487 assert unique_invocation
: self.in_hierarchy
== null
488 var model
= mmodule
.model
489 var res
= model
.mclassdef_hierarchy
.add_node
(self)
490 self.in_hierarchy
= res
491 var mtype
= self.bound_mtype
493 # Here we need to connect the mclassdef to its pairs in the mclassdef_hierarchy
494 # The simpliest way is to attach it to collect_mclassdefs
495 for mclassdef
in mtype
.collect_mclassdefs
(mmodule
) do
496 res
.poset
.add_edge
(self, mclassdef
)
500 # The view of the class definition in `mclassdef_hierarchy'
501 var in_hierarchy
: nullable POSetElement[MClassDef] = null
503 # Is the definition the one that introduced `mclass`?
504 fun is_intro
: Bool do return mclass
.intro
== self
506 # All properties introduced by the classdef
507 var intro_mproperties
: Array[MProperty] = new Array[MProperty]
509 # All property definitions in the class (introductions and redefinitions)
510 var mpropdefs
: Array[MPropDef] = new Array[MPropDef]
513 # A global static type
515 # MType are global to the model; it means that a MType is not bound to a
516 # specific `MModule`.
517 # This characteristic helps the reasoning about static types in a program
518 # since a single MType object always denote the same type.
520 # However, because a MType is global, it does not really have properties
521 # nor have subtypes to a hierarchy since the property and the class hierarchy
522 # depends of a module.
523 # Moreover, virtual types an formal generic parameter types also depends on
524 # a receiver to have sense.
526 # Therefore, most method of the types require a module and an anchor.
527 # The module is used to know what are the classes and the specialization
529 # The anchor is used to know what is the bound of the virtual types and formal
530 # generic parameter types.
532 # MType are not directly usable to get properties. See the `anchor_to' method
533 # and the `MClassType' class.
535 # FIXME: the order of the parameters is not the best. We mus pick on from:
536 # * foo(mmodule, anchor, othertype)
537 # * foo(othertype, anchor, mmodule)
538 # * foo(anchor, mmodule, othertype)
539 # * foo(othertype, mmodule, anchor)
542 # The model of the type
543 fun model
: Model is abstract
545 # Return true if `self' is an subtype of `sup'.
546 # The typing is done using the standard typing policy of Nit.
548 # REQUIRE: anchor == null implies not self.need_anchor and not sup.need_anchor
549 # REQUIRE: anchor != null implies self.can_resolve_for(anchor, null, mmodule) and sup.can_resolve_for(anchor, null, mmodule)
550 fun is_subtype
(mmodule
: MModule, anchor
: nullable MClassType, sup
: MType): Bool
553 if sub
== sup
then return true
554 if anchor
== null then
555 assert not sub
.need_anchor
556 assert not sup
.need_anchor
558 assert sub
.can_resolve_for
(anchor
, null, mmodule
)
559 assert sup
.can_resolve_for
(anchor
, null, mmodule
)
562 # First, resolve the formal types to a common version in the receiver
563 # The trick here is that fixed formal type will be associed to the bound
564 # And unfixed formal types will be associed to a canonical formal type.
565 if sub
isa MParameterType or sub
isa MVirtualType then
566 assert anchor
!= null
567 sub
= sub
.resolve_for
(anchor
.mclass
.mclass_type
, anchor
, mmodule
, false)
569 if sup
isa MParameterType or sup
isa MVirtualType then
570 assert anchor
!= null
571 sup
= sup
.resolve_for
(anchor
.mclass
.mclass_type
, anchor
, mmodule
, false)
574 # Does `sup` accept null or not?
575 # Discard the nullable marker if it exists
576 var sup_accept_null
= false
577 if sup
isa MNullableType then
578 sup_accept_null
= true
580 else if sup
isa MNullType then
581 sup_accept_null
= true
584 # Can `sub` provide null or not?
585 # Thus we can match with `sup_accept_null`
586 # Also discard the nullable marker if it exists
587 if sub
isa MNullableType then
588 if not sup_accept_null
then return false
590 else if sub
isa MNullType then
591 return sup_accept_null
593 # Now the case of direct null and nullable is over.
595 # A unfixed formal type can only accept itself
596 if sup
isa MParameterType or sup
isa MVirtualType then
600 # If `sub` is a formal type, then it is accepted if its bound is accepted
601 if sub
isa MParameterType or sub
isa MVirtualType then
602 assert anchor
!= null
603 sub
= sub
.anchor_to
(mmodule
, anchor
)
605 # Manage the second layer of null/nullable
606 if sub
isa MNullableType then
607 if not sup_accept_null
then return false
609 else if sub
isa MNullType then
610 return sup_accept_null
614 assert sub
isa MClassType # It is the only remaining type
616 if sup
isa MNullType then
617 # `sup` accepts only null
621 assert sup
isa MClassType # It is the only remaining type
623 # Now both are MClassType, we need to dig
625 if sub
== sup
then return true
627 if anchor
== null then anchor
= sub
# UGLY: any anchor will work
628 var resolved_sub
= sub
.anchor_to
(mmodule
, anchor
)
629 var res
= resolved_sub
.collect_mclasses
(mmodule
).has
(sup
.mclass
)
630 if res
== false then return false
631 if not sup
isa MGenericType then return true
632 var sub2
= sub
.supertype_to
(mmodule
, anchor
, sup
.mclass
)
633 assert sub2
.mclass
== sup
.mclass
634 for i
in [0..sup
.mclass
.arity
[ do
635 var sub_arg
= sub2
.arguments
[i
]
636 var sup_arg
= sup
.arguments
[i
]
637 res
= sub_arg
.is_subtype
(mmodule
, anchor
, sup_arg
)
638 if res
== false then return false
643 # The base class type on which self is based
645 # This base type is used to get property (an internally to perform
646 # unsafe type comparison).
648 # Beware: some types (like null) are not based on a class thus this
651 # Basically, this function transform the virtual types and parameter
652 # types to their bounds.
662 # Map[T,U] anchor_to H #-> Map[C,Y]
664 # Explanation of the example:
665 # In H, T is set to C, because "H super G[C]", and U is bound to Y,
666 # because "redef type U: Y". Therefore, Map[T, U] is bound to
669 # ENSURE: not self.need_anchor implies return == self
670 # ENSURE: not return.need_anchor
671 fun anchor_to
(mmodule
: MModule, anchor
: MClassType): MType
673 if not need_anchor
then return self
674 assert not anchor
.need_anchor
675 # Just resolve to the anchor and clear all the virtual types
676 var res
= self.resolve_for
(anchor
, null, mmodule
, true)
677 assert not res
.need_anchor
681 # Does `self' contain a virtual type or a formal generic parameter type?
682 # In order to remove those types, you usually want to use `anchor_to'.
683 fun need_anchor
: Bool do return true
685 # Return the supertype when adapted to a class.
687 # In Nit, for each super-class of a type, there is a equivalent super-type.
691 # class H[V] super G[V, Bool]
692 # H[Int] supertype_to G #-> G[Int, Bool]
694 # REQUIRE: `super_mclass' is a super-class of `self'
695 # REQUIRE: self.need_anchor implies anchor != null and self.can_resolve_for(anchor, null, mmodule)
696 # ENSURE: return.mclass = mclass
697 fun supertype_to
(mmodule
: MModule, anchor
: nullable MClassType, super_mclass
: MClass): MClassType
699 if super_mclass
.arity
== 0 then return super_mclass
.mclass_type
700 if self isa MClassType and self.mclass
== super_mclass
then return self
702 if self.need_anchor
then
703 assert anchor
!= null
704 resolved_self
= self.anchor_to
(mmodule
, anchor
)
708 var supertypes
= resolved_self
.collect_mtypes
(mmodule
)
709 for supertype
in supertypes
do
710 if supertype
.mclass
== super_mclass
then
711 # FIXME: Here, we stop on the first goal. Should we check others and detect inconsistencies?
712 return supertype
.resolve_for
(self, anchor
, mmodule
, false)
718 # Replace formals generic types in self with resolved values in `mtype'
719 # If `cleanup_virtual' is true, then virtual types are also replaced
722 # This function returns self if `need_anchor' is false.
727 # class H[F] super G[F]
730 # Array[E].resolve_for(H[Int]) #-> Array[Int]
731 # Array[E].resolve_for(G[Z], X[Int]) #-> Array[Z]
733 # Explanation of the example:
734 # * Array[E].need_anchor is true because there is a formal generic
736 # * E makes sense for H[Int] because E is a formal parameter of G
738 # * Since "H[F] super G[F]", E is in fact F for H
739 # * More specifically, in H[Int], E is Int
740 # * So, in H[Int], Array[E] is Array[Int]
742 # This function is mainly used to inherit a signature.
743 # Because, unlike `anchor_to', we do not want a full resolution of
744 # a type but only an adapted version of it.
751 # class B super A[Int] end
753 # The signature on foo is (e: E): E
754 # If we resolve the signature for B, we get (e:Int):Int
759 # fun foo(e:E) is abstract
763 # fun bar do a.foo(x) # <- x is here
766 # The first question is: is foo available on `a`?
768 # The static type of a is `A[Array[F]]`, that is an open type.
769 # in order to find a method `foo`, whe must look at a resolved type.
771 # A[Array[F]].anchor_to(B[nullable Object]) #-> A[Array[nullable Object]]
773 # the method `foo` exists in `A[Array[nullable Object]]`, therefore `foo` exists for `a`.
775 # The next question is: what is the accepted types for `x'?
777 # the signature of `foo` is `foo(e:E)`, thus we must resolve the type E
779 # E.resolve_for(A[Array[F]],B[nullable Object]) #-> Array[F]
781 # The resolution can be done because `E` make sense for the class A (see `can_resolve_for`)
783 # TODO: Explain the cleanup_virtual
785 # FIXME: the parameter `cleanup_virtual' is just a bad idea, but having
786 # two function instead of one seems also to be a bad idea.
788 # REQUIRE: can_resolve_for(mtype, anchor, mmodule)
789 # ENSURE: not self.need_anchor implies return == self
790 fun resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule, cleanup_virtual
: Bool): MType is abstract
792 # Can the type be resolved?
794 # In order to resolve open types, the formal types must make sence.
803 # E.can_resolve_for(A[Int]) #-> true, E make sense in A
804 # E.can_resolve_for(B[Int]) #-> false, E does not make sense in B
805 # B[E].can_resolve_for(A[F], B[Object]) #-> true,
806 # B[E] is a red hearing only the E is important,
809 # REQUIRE: anchor != null implies not anchor.need_anchor
810 # REQUIRE: mtype.need_anchor implies anchor != null and mtype.can_resolve_for(anchor, null, mmodule)
811 # ENSURE: not self.need_anchor implies return == true
812 fun can_resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule): Bool is abstract
814 # Return the nullable version of the type
815 # If the type is already nullable then self is returned
816 fun as_nullable
: MType
818 var res
= self.as_nullable_cache
819 if res
!= null then return res
820 res
= new MNullableType(self)
821 self.as_nullable_cache
= res
825 private var as_nullable_cache
: nullable MType = null
828 # The deph of the type seen as a tree.
835 # Formal types have a depth of 1.
841 # The length of the type seen as a tree.
848 # Formal types have a length of 1.
854 # Compute all the classdefs inherited/imported.
855 # The returned set contains:
856 # * the class definitions from `mmodule` and its imported modules
857 # * the class definitions of this type and its super-types
859 # This function is used mainly internally.
861 # REQUIRE: not self.need_anchor
862 fun collect_mclassdefs
(mmodule
: MModule): Set[MClassDef] is abstract
864 # Compute all the super-classes.
865 # This function is used mainly internally.
867 # REQUIRE: not self.need_anchor
868 fun collect_mclasses
(mmodule
: MModule): Set[MClass] is abstract
870 # Compute all the declared super-types.
871 # Super-types are returned as declared in the classdefs (verbatim).
872 # This function is used mainly internally.
874 # REQUIRE: not self.need_anchor
875 fun collect_mtypes
(mmodule
: MModule): Set[MClassType] is abstract
877 # Is the property in self for a given module
878 # This method does not filter visibility or whatever
880 # REQUIRE: not self.need_anchor
881 fun has_mproperty
(mmodule
: MModule, mproperty
: MProperty): Bool
883 assert not self.need_anchor
884 return self.collect_mclassdefs
(mmodule
).has
(mproperty
.intro_mclassdef
)
888 # A type based on a class.
890 # MClassType have properties (see `has_property').
894 # The associated class
897 redef fun model
do return self.mclass
.intro_mmodule
.model
899 private init(mclass
: MClass)
904 # The formal arguments of the type
905 # ENSURE: return.length == self.mclass.arity
906 var arguments
: Array[MType] = new Array[MType]
908 redef fun to_s
do return mclass
.to_s
910 redef fun need_anchor
do return false
912 redef fun anchor_to
(mmodule
: MModule, anchor
: MClassType): MClassType
914 return super.as(MClassType)
917 redef fun resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule, cleanup_virtual
: Bool): MClassType do return self
919 redef fun can_resolve_for
(mtype
, anchor
, mmodule
) do return true
921 redef fun collect_mclassdefs
(mmodule
)
923 assert not self.need_anchor
924 var cache
= self.collect_mclassdefs_cache
925 if not cache
.has_key
(mmodule
) then
926 self.collect_things
(mmodule
)
928 return cache
[mmodule
]
931 redef fun collect_mclasses
(mmodule
)
933 assert not self.need_anchor
934 var cache
= self.collect_mclasses_cache
935 if not cache
.has_key
(mmodule
) then
936 self.collect_things
(mmodule
)
938 return cache
[mmodule
]
941 redef fun collect_mtypes
(mmodule
)
943 assert not self.need_anchor
944 var cache
= self.collect_mtypes_cache
945 if not cache
.has_key
(mmodule
) then
946 self.collect_things
(mmodule
)
948 return cache
[mmodule
]
951 # common implementation for `collect_mclassdefs', `collect_mclasses', and `collect_mtypes'.
952 private fun collect_things
(mmodule
: MModule)
954 var res
= new HashSet[MClassDef]
955 var seen
= new HashSet[MClass]
956 var types
= new HashSet[MClassType]
957 seen
.add
(self.mclass
)
958 var todo
= [self.mclass
]
959 while not todo
.is_empty
do
960 var mclass
= todo
.pop
961 #print "process {mclass}"
962 for mclassdef
in mclass
.mclassdefs
do
963 if not mmodule
.in_importation
<= mclassdef
.mmodule
then continue
964 #print " process {mclassdef}"
966 for supertype
in mclassdef
.supertypes
do
968 var superclass
= supertype
.mclass
969 if seen
.has
(superclass
) then continue
970 #print " add {superclass}"
976 collect_mclassdefs_cache
[mmodule
] = res
977 collect_mclasses_cache
[mmodule
] = seen
978 collect_mtypes_cache
[mmodule
] = types
981 private var collect_mclassdefs_cache
: HashMap[MModule, Set[MClassDef]] = new HashMap[MModule, Set[MClassDef]]
982 private var collect_mclasses_cache
: HashMap[MModule, Set[MClass]] = new HashMap[MModule, Set[MClass]]
983 private var collect_mtypes_cache
: HashMap[MModule, Set[MClassType]] = new HashMap[MModule, Set[MClassType]]
987 # A type based on a generic class.
988 # A generic type a just a class with additional formal generic arguments.
992 private init(mclass
: MClass, arguments
: Array[MType])
995 assert self.mclass
.arity
== arguments
.length
996 self.arguments
= arguments
998 self.need_anchor
= false
999 for t
in arguments
do
1000 if t
.need_anchor
then
1001 self.need_anchor
= true
1006 self.to_s
= "{mclass}[{arguments.join(", ")}]"
1009 # Recursively print the type of the arguments within brackets.
1010 # Example: "Map[String, List[Int]]"
1011 redef var to_s
: String
1013 redef var need_anchor
: Bool
1015 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1017 if not need_anchor
then return self
1018 assert can_resolve_for
(mtype
, anchor
, mmodule
)
1019 var types
= new Array[MType]
1020 for t
in arguments
do
1021 types
.add
(t
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
))
1023 return mclass
.get_mtype
(types
)
1026 redef fun can_resolve_for
(mtype
, anchor
, mmodule
)
1028 if not need_anchor
then return true
1029 for t
in arguments
do
1030 if not t
.can_resolve_for
(mtype
, anchor
, mmodule
) then return false
1039 for a
in self.arguments
do
1041 if d
> dmax
then dmax
= d
1049 for a
in self.arguments
do
1056 # A virtual formal type.
1060 # The property associated with the type.
1061 # Its the definitions of this property that determine the bound or the virtual type.
1062 var mproperty
: MProperty
1064 redef fun model
do return self.mproperty
.intro_mclassdef
.mmodule
.model
1066 # Lookup the bound for a given resolved_receiver
1067 # The result may be a other virtual type (or a parameter type)
1069 # The result is returned exactly as declared in the "type" property (verbatim).
1071 # In case of conflict, the method aborts.
1072 fun lookup_bound
(mmodule
: MModule, resolved_receiver
: MType): MType
1074 assert not resolved_receiver
.need_anchor
1075 var props
= self.mproperty
.lookup_definitions
(mmodule
, resolved_receiver
)
1076 if props
.is_empty
then
1078 else if props
.length
== 1 then
1079 return props
.first
.as(MVirtualTypeDef).bound
.as(not null)
1081 var types
= new ArraySet[MType]
1083 types
.add
(p
.as(MVirtualTypeDef).bound
.as(not null))
1085 if types
.length
== 1 then
1091 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1093 assert can_resolve_for
(mtype
, anchor
, mmodule
)
1094 # self is a virtual type declared (or inherited) in mtype
1095 # The point of the function it to get the bound of the virtual type that make sense for mtype
1096 # But because mtype is maybe a virtual/formal type, we need to get a real receiver first
1097 #print "{class_name}: {self}/{mtype}/{anchor}?"
1098 var resolved_reciever
1099 if mtype
.need_anchor
then
1100 assert anchor
!= null
1101 resolved_reciever
= mtype
.resolve_for
(anchor
, null, mmodule
, true)
1103 resolved_reciever
= mtype
1105 # Now, we can get the bound
1106 var verbatim_bound
= lookup_bound
(mmodule
, resolved_reciever
)
1107 # The bound is exactly as declared in the "type" property, so we must resolve it again
1108 var res
= verbatim_bound
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1109 #print "{class_name}: {self}/{mtype}/{anchor} -> {self}/{resolved_reciever}/{anchor} -> {verbatim_bound}/{mtype}/{anchor} -> {res}"
1111 # What to return here? There is a bunch a special cases:
1112 # If 'cleanup_virtual' we must return the resolved type, since we cannot return self
1113 if cleanup_virtual
then return res
1114 # 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
1115 if resolved_reciever
isa MNullableType then resolved_reciever
= resolved_reciever
.mtype
1116 if resolved_reciever
.as(MClassType).mclass
.kind
== enum_kind
then return res
1117 # 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.
1118 if res
isa MVirtualType then return res
1119 # 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
1120 if res
isa MClassType and res
.mclass
.kind
== enum_kind
then return res
1121 # TODO: Add 'fixed' virtual type in the specification.
1122 # TODO: What if bound to a MParameterType?
1123 # Note that Nullable types can always be redefined by the non nullable version, so there is no specific case on it.
1125 # If anything apply, then `self' cannot be resolved, so return self
1129 redef fun can_resolve_for
(mtype
, anchor
, mmodule
)
1131 if mtype
.need_anchor
then
1132 assert anchor
!= null
1133 mtype
= mtype
.anchor_to
(mmodule
, anchor
)
1135 return mtype
.has_mproperty
(mmodule
, mproperty
)
1138 redef fun to_s
do return self.mproperty
.to_s
1140 init(mproperty
: MProperty)
1142 self.mproperty
= mproperty
1146 # The type associated the a formal parameter generic type of a class
1148 # Each parameter type is associated to a specific class.
1149 # It's mean that all refinements of a same class "share" the parameter type,
1150 # but that a generic subclass has its on parameter types.
1152 # However, in the sense of the meta-model, the a parameter type of a class is
1153 # a valid types in a subclass. The "in the sense of the meta-model" is
1154 # important because, in the Nit language, the programmer cannot refers
1155 # directly to the parameter types of the super-classes.
1159 # fun e: E is abstract
1164 # In the class definition B[F], `F' is a valid type but `E' is not.
1165 # However, `self.e' is a valid method call, and the signature of `e' is
1168 # Note that parameter types are shared among class refinements.
1169 # Therefore parameter only have an internal name (see `to_s' for details).
1170 # TODO: Add a 'name_for' to get better messages.
1171 class MParameterType
1174 # The generic class where the parameter belong
1177 redef fun model
do return self.mclass
.intro_mmodule
.model
1179 # The position of the parameter (0 for the first parameter)
1180 # FIXME: is `position' a better name?
1183 # Internal name of the parameter type
1184 # Names of parameter types changes in each class definition
1185 # Therefore, this method return an internal name.
1186 # Example: return "G#1" for the second parameter of the class G
1187 # FIXME: add a way to get the real name in a classdef
1188 redef fun to_s
do return "{mclass}#{rank}"
1190 # Resolve the bound for a given resolved_receiver
1191 # The result may be a other virtual type (or a parameter type)
1192 fun lookup_bound
(mmodule
: MModule, resolved_receiver
: MType): MType
1194 assert not resolved_receiver
.need_anchor
1195 var goalclass
= self.mclass
1196 var supertypes
= resolved_receiver
.collect_mtypes
(mmodule
)
1197 for t
in supertypes
do
1198 if t
.mclass
== goalclass
then
1199 # Yeah! c specialize goalclass with a "super `t'". So the question is what is the argument of f
1200 # FIXME: Here, we stop on the first goal. Should we check others and detect inconsistencies?
1201 var res
= t
.arguments
[self.rank
]
1208 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1210 assert can_resolve_for
(mtype
, anchor
, mmodule
)
1211 #print "{class_name}: {self}/{mtype}/{anchor}?"
1213 if mtype
isa MGenericType and mtype
.mclass
== self.mclass
then
1214 return mtype
.arguments
[self.rank
]
1217 # self is a parameter type of mtype (or of a super-class of mtype)
1218 # The point of the function it to get the bound of the virtual type that make sense for mtype
1219 # But because mtype is maybe a virtual/formal type, we need to get a real receiver first
1220 # FIXME: What happend here is far from clear. Thus this part must be validated and clarified
1221 var resolved_receiver
1222 if mtype
.need_anchor
then
1223 assert anchor
!= null
1224 resolved_receiver
= mtype
.resolve_for
(anchor
.mclass
.mclass_type
, anchor
, mmodule
, true)
1226 resolved_receiver
= mtype
1228 if resolved_receiver
isa MNullableType then resolved_receiver
= resolved_receiver
.mtype
1229 if resolved_receiver
isa MParameterType then
1230 assert resolved_receiver
.mclass
== anchor
.mclass
1231 resolved_receiver
= anchor
.arguments
[resolved_receiver
.rank
]
1232 if resolved_receiver
isa MNullableType then resolved_receiver
= resolved_receiver
.mtype
1234 assert resolved_receiver
isa MClassType
1236 # Eh! The parameter is in the current class.
1237 # So we return the corresponding argument, no mater what!
1238 if resolved_receiver
.mclass
== self.mclass
then
1239 var res
= resolved_receiver
.arguments
[self.rank
]
1240 #print "{class_name}: {self}/{mtype}/{anchor} -> direct {res}"
1244 if resolved_receiver
.need_anchor
then
1245 assert anchor
!= null
1246 resolved_receiver
= resolved_receiver
.resolve_for
(anchor
, null, mmodule
, false)
1248 # Now, we can get the bound
1249 var verbatim_bound
= lookup_bound
(mmodule
, resolved_receiver
)
1250 # The bound is exactly as declared in the "type" property, so we must resolve it again
1251 var res
= verbatim_bound
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1253 #print "{class_name}: {self}/{mtype}/{anchor} -> indirect {res}"
1258 redef fun can_resolve_for
(mtype
, anchor
, mmodule
)
1260 if mtype
.need_anchor
then
1261 assert anchor
!= null
1262 mtype
= mtype
.anchor_to
(mmodule
, anchor
)
1264 return mtype
.collect_mclassdefs
(mmodule
).has
(mclass
.intro
)
1267 init(mclass
: MClass, rank
: Int)
1269 self.mclass
= mclass
1274 # A type prefixed with "nullable"
1278 # The base type of the nullable type
1281 redef fun model
do return self.mtype
.model
1286 self.to_s
= "nullable {mtype}"
1289 redef var to_s
: String
1291 redef fun need_anchor
do return mtype
.need_anchor
1292 redef fun as_nullable
do return self
1293 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1295 var res
= self.mtype
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1296 return res
.as_nullable
1299 redef fun can_resolve_for
(mtype
, anchor
, mmodule
)
1301 return self.mtype
.can_resolve_for
(mtype
, anchor
, mmodule
)
1304 redef fun depth
do return self.mtype
.depth
1306 redef fun length
do return self.mtype
.length
1308 redef fun collect_mclassdefs
(mmodule
)
1310 assert not self.need_anchor
1311 return self.mtype
.collect_mclassdefs
(mmodule
)
1314 redef fun collect_mclasses
(mmodule
)
1316 assert not self.need_anchor
1317 return self.mtype
.collect_mclasses
(mmodule
)
1320 redef fun collect_mtypes
(mmodule
)
1322 assert not self.need_anchor
1323 return self.mtype
.collect_mtypes
(mmodule
)
1327 # The type of the only value null
1329 # The is only one null type per model, see `MModel::null_type'.
1332 redef var model
: Model
1333 protected init(model
: Model)
1337 redef fun to_s
do return "null"
1338 redef fun as_nullable
do return self
1339 redef fun need_anchor
do return false
1340 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
) do return self
1341 redef fun can_resolve_for
(mtype
, anchor
, mmodule
) do return true
1343 redef fun collect_mclassdefs
(mmodule
) do return new HashSet[MClassDef]
1345 redef fun collect_mclasses
(mmodule
) do return new HashSet[MClass]
1347 redef fun collect_mtypes
(mmodule
) do return new HashSet[MClassType]
1350 # A signature of a method (or a closure)
1354 # The each parameter (in order)
1355 var mparameters
: Array[MParameter]
1357 var mclosures
= new Array[MParameter]
1359 # The return type (null for a procedure)
1360 var return_mtype
: nullable MType
1365 var t
= self.return_mtype
1366 if t
!= null then dmax
= t
.depth
1367 for p
in mparameters
do
1368 var d
= p
.mtype
.depth
1369 if d
> dmax
then dmax
= d
1371 for p
in mclosures
do
1372 var d
= p
.mtype
.depth
1373 if d
> dmax
then dmax
= d
1381 var t
= self.return_mtype
1382 if t
!= null then res
+= t
.length
1383 for p
in mparameters
do
1384 res
+= p
.mtype
.length
1386 for p
in mclosures
do
1387 res
+= p
.mtype
.length
1392 # REQUIRE: 1 <= mparameters.count p -> p.is_vararg
1393 init(mparameters
: Array[MParameter], return_mtype
: nullable MType)
1395 var vararg_rank
= -1
1396 for i
in [0..mparameters
.length
[ do
1397 var parameter
= mparameters
[i
]
1398 if parameter
.is_vararg
then
1399 assert vararg_rank
== -1
1403 self.mparameters
= mparameters
1404 self.return_mtype
= return_mtype
1405 self.vararg_rank
= vararg_rank
1408 # The rank of the ellipsis (...) for vararg (starting from 0).
1409 # value is -1 if there is no vararg.
1410 # Example: for "(a: Int, b: Bool..., c: Char)" #-> vararg_rank=1
1411 var vararg_rank
: Int
1413 # The number or parameters
1414 fun arity
: Int do return mparameters
.length
1419 if not mparameters
.is_empty
then
1421 for i
in [0..mparameters
.length
[ do
1422 var mparameter
= mparameters
[i
]
1423 if i
> 0 then b
.append
(", ")
1424 b
.append
(mparameter
.name
)
1426 b
.append
(mparameter
.mtype
.to_s
)
1427 if mparameter
.is_vararg
then
1433 var ret
= self.return_mtype
1441 redef fun resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule, cleanup_virtual
: Bool): MSignature
1443 var params
= new Array[MParameter]
1444 for p
in self.mparameters
do
1445 params
.add
(p
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
))
1447 var ret
= self.return_mtype
1449 ret
= ret
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1451 var res
= new MSignature(params
, ret
)
1452 for p
in self.mclosures
do
1453 res
.mclosures
.add
(p
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
))
1459 # A parameter in a signature
1461 # The name of the parameter
1464 # The static type of the parameter
1467 # Is the parameter a vararg?
1470 fun resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule, cleanup_virtual
: Bool): MParameter
1472 if not self.mtype
.need_anchor
then return self
1473 var newtype
= self.mtype
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1474 var res
= new MParameter(self.name
, newtype
, self.is_vararg
)
1479 # A service (global property) that generalize method, attribute, etc.
1481 # MProperty are global to the model; it means that a MProperty is not bound
1482 # to a specific `MModule` nor a specific `MClass`.
1484 # A MProperty gather definitions (see `mpropdefs') ; one for the introduction
1485 # and the other in subclasses and in refinements.
1487 # A MProperty is used to denotes services in polymorphic way (ie. independent
1488 # of any dynamic type).
1489 # For instance, a call site "x.foo" is associated to a MProperty.
1490 abstract class MProperty
1491 # The associated MPropDef subclass.
1492 # The two specialization hierarchy are symmetric.
1493 type MPROPDEF: MPropDef
1495 # The classdef that introduce the property
1496 # While a property is not bound to a specific module, or class,
1497 # the introducing mclassdef is used for naming and visibility
1498 var intro_mclassdef
: MClassDef
1500 # The (short) name of the property
1503 # The canonical name of the property
1504 # Example: "owner::my_module::MyClass::my_method"
1505 fun full_name
: String
1507 return "{self.intro_mclassdef.mmodule.full_name}::{self.intro_mclassdef.mclass.name}::{name}"
1510 # The visibility of the property
1511 var visibility
: MVisibility
1513 init(intro_mclassdef
: MClassDef, name
: String, visibility
: MVisibility)
1515 self.intro_mclassdef
= intro_mclassdef
1517 self.visibility
= visibility
1518 intro_mclassdef
.intro_mproperties
.add
(self)
1519 var model
= intro_mclassdef
.mmodule
.model
1520 model
.mproperties_by_name
.add_one
(name
, self)
1521 model
.mproperties
.add
(self)
1524 # All definitions of the property.
1525 # The first is the introduction,
1526 # The other are redefinitions (in refinements and in subclasses)
1527 var mpropdefs
: Array[MPROPDEF] = new Array[MPROPDEF]
1529 # The definition that introduced the property
1530 # Warning: the introduction is the first `MPropDef' object
1531 # associated to self. If self is just created without having any
1532 # associated definition, this method will abort
1533 fun intro
: MPROPDEF do return mpropdefs
.first
1536 redef fun to_s
do return name
1538 # Return the most specific property definitions defined or inherited by a type.
1539 # The selection knows that refinement is stronger than specialization;
1540 # however, in case of conflict more than one property are returned.
1541 # If mtype does not know mproperty then an empty array is returned.
1543 # If you want the really most specific property, then look at `lookup_first_definition`
1544 fun lookup_definitions
(mmodule
: MModule, mtype
: MType): Array[MPROPDEF]
1546 assert not mtype
.need_anchor
1547 if mtype
isa MNullableType then mtype
= mtype
.mtype
1549 var cache
= self.lookup_definitions_cache
[mmodule
, mtype
]
1550 if cache
!= null then return cache
1552 #print "select prop {mproperty} for {mtype} in {self}"
1553 # First, select all candidates
1554 var candidates
= new Array[MPROPDEF]
1555 for mpropdef
in self.mpropdefs
do
1556 # If the definition is not imported by the module, then skip
1557 if not mmodule
.in_importation
<= mpropdef
.mclassdef
.mmodule
then continue
1558 # If the definition is not inherited by the type, then skip
1559 if not mtype
.is_subtype
(mmodule
, null, mpropdef
.mclassdef
.bound_mtype
) then continue
1561 candidates
.add
(mpropdef
)
1563 # Fast track for only one candidate
1564 if candidates
.length
<= 1 then
1565 self.lookup_definitions_cache
[mmodule
, mtype
] = candidates
1569 # Second, filter the most specific ones
1570 var res
= new Array[MPROPDEF]
1571 for pd1
in candidates
do
1572 var cd1
= pd1
.mclassdef
1575 for pd2
in candidates
do
1576 if pd2
== pd1
then continue # do not compare with self!
1577 var cd2
= pd2
.mclassdef
1579 if c2
.mclass_type
== c1
.mclass_type
then
1580 if cd2
.mmodule
.in_importation
<= cd1
.mmodule
then
1581 # cd2 refines cd1; therefore we skip pd1
1585 else if cd2
.bound_mtype
.is_subtype
(mmodule
, null, cd1
.bound_mtype
) then
1586 # cd2 < cd1; therefore we skip pd1
1595 if res
.is_empty
then
1596 print
"All lost! {candidates.join(", ")}"
1597 # FIXME: should be abort!
1599 self.lookup_definitions_cache
[mmodule
, mtype
] = res
1603 private var lookup_definitions_cache
: HashMap2[MModule, MType, Array[MPROPDEF]] = new HashMap2[MModule, MType, Array[MPROPDEF]]
1605 # Return the most specific property definitions inherited by a type.
1606 # The selection knows that refinement is stronger than specialization;
1607 # however, in case of conflict more than one property are returned.
1608 # If mtype does not know mproperty then an empty array is returned.
1610 # If you want the really most specific property, then look at `lookup_next_definition`
1612 # FIXME: Move to MPropDef?
1613 fun lookup_super_definitions
(mmodule
: MModule, mtype
: MType): Array[MPropDef]
1615 assert not mtype
.need_anchor
1616 if mtype
isa MNullableType then mtype
= mtype
.mtype
1618 # First, select all candidates
1619 var candidates
= new Array[MPropDef]
1620 for mpropdef
in self.mpropdefs
do
1621 # If the definition is not imported by the module, then skip
1622 if not mmodule
.in_importation
<= mpropdef
.mclassdef
.mmodule
then continue
1623 # If the definition is not inherited by the type, then skip
1624 if not mtype
.is_subtype
(mmodule
, null, mpropdef
.mclassdef
.bound_mtype
) then continue
1625 # If the definition is defined by the type, then skip (we want the super, so e skip the current)
1626 if mtype
== mpropdef
.mclassdef
.bound_mtype
and mmodule
== mpropdef
.mclassdef
.mmodule
then continue
1628 candidates
.add
(mpropdef
)
1630 # Fast track for only one candidate
1631 if candidates
.length
<= 1 then return candidates
1633 # Second, filter the most specific ones
1634 var res
= new Array[MPropDef]
1635 for pd1
in candidates
do
1636 var cd1
= pd1
.mclassdef
1639 for pd2
in candidates
do
1640 if pd2
== pd1
then continue # do not compare with self!
1641 var cd2
= pd2
.mclassdef
1643 if c2
.mclass_type
== c1
.mclass_type
then
1644 if cd2
.mmodule
.in_importation
<= cd1
.mmodule
then
1645 # cd2 refines cd1; therefore we skip pd1
1649 else if cd2
.bound_mtype
.is_subtype
(mmodule
, null, cd1
.bound_mtype
) then
1650 # cd2 < cd1; therefore we skip pd1
1659 if res
.is_empty
then
1660 print
"All lost! {candidates.join(", ")}"
1661 # FIXME: should be abort!
1666 # Return the most specific definition in the linearization of `mtype`.
1668 # If you want to know the next properties in the linearization,
1669 # look at `MPropDef::lookup_next_definition`.
1671 # FIXME: the linearisation is still unspecified
1673 # REQUIRE: not mtype.need_anchor
1674 # REQUIRE: mtype.has_mproperty(mmodule, self)
1675 fun lookup_first_definition
(mmodule
: MModule, mtype
: MType): MPROPDEF
1677 return lookup_all_definitions
(mmodule
, mtype
).first
1680 # Return all definitions in a linearisation order
1681 # Most speficic first, most general last
1682 fun lookup_all_definitions
(mmodule
: MModule, mtype
: MType): Array[MPROPDEF]
1684 assert not mtype
.need_anchor
1685 if mtype
isa MNullableType then mtype
= mtype
.mtype
1687 var cache
= self.lookup_all_definitions_cache
[mmodule
, mtype
]
1688 if cache
!= null then return cache
1690 #print "select prop {mproperty} for {mtype} in {self}"
1691 # First, select all candidates
1692 var candidates
= new Array[MPROPDEF]
1693 for mpropdef
in self.mpropdefs
do
1694 # If the definition is not imported by the module, then skip
1695 if not mmodule
.in_importation
<= mpropdef
.mclassdef
.mmodule
then continue
1696 # If the definition is not inherited by the type, then skip
1697 if not mtype
.is_subtype
(mmodule
, null, mpropdef
.mclassdef
.bound_mtype
) then continue
1699 candidates
.add
(mpropdef
)
1701 # Fast track for only one candidate
1702 if candidates
.length
<= 1 then
1703 self.lookup_all_definitions_cache
[mmodule
, mtype
] = candidates
1707 mmodule
.linearize_mpropdefs
(candidates
)
1708 candidates
= candidates
.reversed
1709 self.lookup_all_definitions_cache
[mmodule
, mtype
] = candidates
1713 private var lookup_all_definitions_cache
: HashMap2[MModule, MType, Array[MPROPDEF]] = new HashMap2[MModule, MType, Array[MPROPDEF]]
1720 redef type MPROPDEF: MMethodDef
1722 init(intro_mclassdef
: MClassDef, name
: String, visibility
: MVisibility)
1727 # Is the property a constructor?
1728 # Warning, this property can be inherited by subclasses with or without being a constructor
1729 # therefore, you should use `is_init_for' the verify if the property is a legal constructor for a given class
1730 var is_init
: Bool writable = false
1732 # The the property a 'new' contructor?
1733 var is_new
: Bool writable = false
1735 # Is the property a legal constructor for a given class?
1736 # As usual, visibility is not considered.
1737 # FIXME not implemented
1738 fun is_init_for
(mclass
: MClass): Bool
1744 # A global attribute
1748 redef type MPROPDEF: MAttributeDef
1750 init(intro_mclassdef
: MClassDef, name
: String, visibility
: MVisibility)
1756 # A global virtual type
1757 class MVirtualTypeProp
1760 redef type MPROPDEF: MVirtualTypeDef
1762 init(intro_mclassdef
: MClassDef, name
: String, visibility
: MVisibility)
1767 # The formal type associated to the virtual type property
1768 var mvirtualtype
: MVirtualType = new MVirtualType(self)
1771 # A definition of a property (local property)
1773 # Unlike MProperty, a MPropDef is a local definition that belong to a
1774 # specific class definition (which belong to a specific module)
1775 abstract class MPropDef
1777 # The associated MProperty subclass.
1778 # the two specialization hierarchy are symmetric
1779 type MPROPERTY: MProperty
1782 type MPROPDEF: MPropDef
1784 # The origin of the definition
1785 var location
: Location
1787 # The class definition where the property definition is
1788 var mclassdef
: MClassDef
1790 # The associated global property
1791 var mproperty
: MPROPERTY
1793 init(mclassdef
: MClassDef, mproperty
: MPROPERTY, location
: Location)
1795 self.mclassdef
= mclassdef
1796 self.mproperty
= mproperty
1797 self.location
= location
1798 mclassdef
.mpropdefs
.add
(self)
1799 mproperty
.mpropdefs
.add
(self)
1800 self.to_s
= "{mclassdef}#{mproperty}"
1803 # Internal name combining the module, the class and the property
1804 # Example: "mymodule#MyClass#mymethod"
1805 redef var to_s
: String
1807 # Is self the definition that introduce the property?
1808 fun is_intro
: Bool do return mproperty
.intro
== self
1810 # Return the next definition in linearization of `mtype`.
1812 # This method is used to determine what method is called by a super.
1814 # REQUIRE: not mtype.need_anchor
1815 fun lookup_next_definition
(mmodule
: MModule, mtype
: MType): MPROPDEF
1817 assert not mtype
.need_anchor
1819 var mpropdefs
= self.mproperty
.lookup_all_definitions
(mmodule
, mtype
)
1820 var i
= mpropdefs
.iterator
1821 while i
.is_ok
and i
.item
!= self do i
.next
1822 assert has_property
: i
.is_ok
1824 assert has_next_property
: i
.is_ok
1829 # A local definition of a method
1833 redef type MPROPERTY: MMethod
1834 redef type MPROPDEF: MMethodDef
1836 init(mclassdef
: MClassDef, mproperty
: MPROPERTY, location
: Location)
1841 # The signature attached to the property definition
1842 var msignature
: nullable MSignature writable = null
1844 # The the method definition abstract?
1845 var is_abstract
: Bool writable = false
1848 # A local definition of an attribute
1852 redef type MPROPERTY: MAttribute
1853 redef type MPROPDEF: MAttributeDef
1855 init(mclassdef
: MClassDef, mproperty
: MPROPERTY, location
: Location)
1860 # The static type of the attribute
1861 var static_mtype
: nullable MType writable = null
1864 # A local definition of a virtual type
1865 class MVirtualTypeDef
1868 redef type MPROPERTY: MVirtualTypeProp
1869 redef type MPROPDEF: MVirtualTypeDef
1871 init(mclassdef
: MClassDef, mproperty
: MPROPERTY, location
: Location)
1876 # The bound of the virtual type
1877 var bound
: nullable MType writable = null
1888 # Note this class is basically an enum.
1889 # FIXME: use a real enum once user-defined enums are available
1891 redef var to_s
: String
1893 # Is a constructor required?
1895 private init(s
: String, need_init
: Bool)
1898 self.need_init
= need_init
1902 fun abstract_kind
: MClassKind do return once
new MClassKind("abstract class", true)
1903 fun concrete_kind
: MClassKind do return once
new MClassKind("class", true)
1904 fun interface_kind
: MClassKind do return once
new MClassKind("interface", false)
1905 fun enum_kind
: MClassKind do return once
new MClassKind("enum", false)
1906 fun extern_kind
: MClassKind do return once
new MClassKind("extern", false)