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
31 private import more_collections
35 var mclasses
: Array[MClass] = new Array[MClass]
37 # All known properties
38 var mproperties
: Array[MProperty] = new Array[MProperty]
40 # Hierarchy of class definition.
42 # Each classdef is associated with its super-classdefs in regard to
43 # its module of definition.
44 var mclassdef_hierarchy
: POSet[MClassDef] = new POSet[MClassDef]
46 # Class-type hierarchy restricted to the introduction.
48 # The idea is that what is true on introduction is always true whatever
49 # the module considered.
50 # Therefore, this hierarchy is used for a fast positive subtype check.
52 # This poset will evolve in a monotonous way:
53 # * Two non connected nodes will remain unconnected
54 # * New nodes can appear with new edges
55 private var intro_mtype_specialization_hierarchy
: POSet[MClassType] = new POSet[MClassType]
57 # Global overlapped class-type hierarchy.
58 # The hierarchy when all modules are combined.
59 # Therefore, this hierarchy is used for a fast negative subtype check.
61 # This poset will evolve in an anarchic way. Loops can even be created.
63 # FIXME decide what to do on loops
64 private var full_mtype_specialization_hierarchy
: POSet[MClassType] = new POSet[MClassType]
66 # Collections of classes grouped by their short name
67 private var mclasses_by_name
: MultiHashMap[String, MClass] = new MultiHashMap[String, MClass]
69 # Return all class named `name`.
71 # If such a class does not exist, null is returned
72 # (instead of an empty array)
74 # Visibility or modules are not considered
75 fun get_mclasses_by_name
(name
: String): nullable Array[MClass]
77 if mclasses_by_name
.has_key
(name
) then
78 return mclasses_by_name
[name
]
84 # Collections of properties grouped by their short name
85 private var mproperties_by_name
: MultiHashMap[String, MProperty] = new MultiHashMap[String, MProperty]
87 # Return all properties named `name`.
89 # If such a property does not exist, null is returned
90 # (instead of an empty array)
92 # Visibility or modules are not considered
93 fun get_mproperties_by_name
(name
: String): nullable Array[MProperty]
95 if not mproperties_by_name
.has_key
(name
) then
98 return mproperties_by_name
[name
]
103 var null_type
: MNullType = new MNullType(self)
105 # Build an ordered tree with from `concerns`
106 fun concerns_tree
(mconcerns
: Collection[MConcern]): ConcernsTree do
107 var seen
= new HashSet[MConcern]
108 var res
= new ConcernsTree
110 var todo
= new Array[MConcern]
111 todo
.add_all mconcerns
113 while not todo
.is_empty
do
115 if seen
.has
(c
) then continue
116 var pc
= c
.parent_concern
130 # An OrderedTree that can be easily refined for display purposes
132 super OrderedTree[MConcern]
136 # All the classes introduced in the module
137 var intro_mclasses
: Array[MClass] = new Array[MClass]
139 # All the class definitions of the module
140 # (introduction and refinement)
141 var mclassdefs
: Array[MClassDef] = new Array[MClassDef]
143 # Does the current module has a given class `mclass`?
144 # Return true if the mmodule introduces, refines or imports a class.
145 # Visibility is not considered.
146 fun has_mclass
(mclass
: MClass): Bool
148 return self.in_importation
<= mclass
.intro_mmodule
151 # Full hierarchy of introduced ans imported classes.
153 # Create a new hierarchy got by flattening the classes for the module
154 # and its imported modules.
155 # Visibility is not considered.
157 # Note: this function is expensive and is usually used for the main
158 # module of a program only. Do not use it to do you own subtype
160 fun flatten_mclass_hierarchy
: POSet[MClass]
162 var res
= self.flatten_mclass_hierarchy_cache
163 if res
!= null then return res
164 res
= new POSet[MClass]
165 for m
in self.in_importation
.greaters
do
166 for cd
in m
.mclassdefs
do
169 for s
in cd
.supertypes
do
170 res
.add_edge
(c
, s
.mclass
)
174 self.flatten_mclass_hierarchy_cache
= res
178 # Sort a given array of classes using the linerarization order of the module
179 # The most general is first, the most specific is last
180 fun linearize_mclasses
(mclasses
: Array[MClass])
182 self.flatten_mclass_hierarchy
.sort
(mclasses
)
185 # Sort a given array of class definitions using the linerarization order of the module
186 # the refinement link is stronger than the specialisation link
187 # The most general is first, the most specific is last
188 fun linearize_mclassdefs
(mclassdefs
: Array[MClassDef])
190 var sorter
= new MClassDefSorter(self)
191 sorter
.sort
(mclassdefs
)
194 # Sort a given array of property definitions using the linerarization order of the module
195 # the refinement link is stronger than the specialisation link
196 # The most general is first, the most specific is last
197 fun linearize_mpropdefs
(mpropdefs
: Array[MPropDef])
199 var sorter
= new MPropDefSorter(self)
200 sorter
.sort
(mpropdefs
)
203 private var flatten_mclass_hierarchy_cache
: nullable POSet[MClass] = null
205 # The primitive type `Object`, the root of the class hierarchy
206 fun object_type
: MClassType
208 var res
= self.object_type_cache
209 if res
!= null then return res
210 res
= self.get_primitive_class
("Object").mclass_type
211 self.object_type_cache
= res
215 private var object_type_cache
: nullable MClassType
217 # The primitive type `Bool`
218 fun bool_type
: MClassType
220 var res
= self.bool_type_cache
221 if res
!= null then return res
222 res
= self.get_primitive_class
("Bool").mclass_type
223 self.bool_type_cache
= res
227 private var bool_type_cache
: nullable MClassType
229 # The primitive type `Sys`, the main type of the program, if any
230 fun sys_type
: nullable MClassType
232 var clas
= self.model
.get_mclasses_by_name
("Sys")
233 if clas
== null then return null
234 return get_primitive_class
("Sys").mclass_type
237 fun finalizable_type
: nullable MClassType
239 var clas
= self.model
.get_mclasses_by_name
("Finalizable")
240 if clas
== null then return null
241 return get_primitive_class
("Finalizable").mclass_type
244 # Force to get the primitive class named `name` or abort
245 fun get_primitive_class
(name
: String): MClass
247 var cla
= self.model
.get_mclasses_by_name
(name
)
249 if name
== "Bool" then
250 var c
= new MClass(self, name
, 0, enum_kind
, public_visibility
)
251 var cladef
= new MClassDef(self, c
.mclass_type
, new Location(null, 0,0,0,0), new Array[String])
254 print
("Fatal Error: no primitive class {name}")
257 if cla
.length
!= 1 then
258 var msg
= "Fatal Error: more than one primitive class {name}:"
259 for c
in cla
do msg
+= " {c.full_name}"
266 # Try to get the primitive method named `name` on the type `recv`
267 fun try_get_primitive_method
(name
: String, recv
: MClass): nullable MMethod
269 var props
= self.model
.get_mproperties_by_name
(name
)
270 if props
== null then return null
271 var res
: nullable MMethod = null
272 for mprop
in props
do
273 assert mprop
isa MMethod
274 var intro
= mprop
.intro_mclassdef
275 for mclassdef
in recv
.mclassdefs
do
276 if not self.in_importation
.greaters
.has
(mclassdef
.mmodule
) then continue
277 if not mclassdef
.in_hierarchy
.greaters
.has
(intro
) then continue
280 else if res
!= mprop
then
281 print
("Fatal Error: ambigous property name '{name}'; conflict between {mprop.full_name} and {res.full_name}")
290 private class MClassDefSorter
291 super AbstractSorter[MClassDef]
293 redef fun compare
(a
, b
)
297 if ca
!= cb
then return mmodule
.flatten_mclass_hierarchy
.compare
(ca
, cb
)
298 return mmodule
.model
.mclassdef_hierarchy
.compare
(a
, b
)
302 private class MPropDefSorter
303 super AbstractSorter[MPropDef]
305 redef fun compare
(pa
, pb
)
311 if ca
!= cb
then return mmodule
.flatten_mclass_hierarchy
.compare
(ca
, cb
)
312 return mmodule
.model
.mclassdef_hierarchy
.compare
(a
, b
)
318 # `MClass` are global to the model; it means that a `MClass` is not bound to a
319 # specific `MModule`.
321 # This characteristic helps the reasoning about classes in a program since a
322 # single `MClass` object always denote the same class.
324 # The drawback is that classes (`MClass`) contain almost nothing by themselves.
325 # These do not really have properties nor belong to a hierarchy since the property and the
326 # hierarchy of a class depends of the refinement in the modules.
328 # Most services on classes require the precision of a module, and no one can asks what are
329 # the super-classes of a class nor what are properties of a class without precising what is
330 # the module considered.
332 # For instance, during the typing of a source-file, the module considered is the module of the file.
333 # eg. the question *is the method `foo` exists in the class `Bar`?* must be reformulated into
334 # *is the method `foo` exists in the class `Bar` in the current module?*
336 # During some global analysis, the module considered may be the main module of the program.
340 # The module that introduce the class
341 # While classes are not bound to a specific module,
342 # the introducing module is used for naming an visibility
343 var intro_mmodule
: MModule
345 # The short name of the class
346 # In Nit, the name of a class cannot evolve in refinements
347 redef var name
: String
349 # The canonical name of the class
350 # Example: `"owner::module::MyClass"`
351 fun full_name
: String
353 return "{self.intro_mmodule.full_name}::{name}"
356 # The number of generic formal parameters
357 # 0 if the class is not generic
360 # The kind of the class (interface, abstract class, etc.)
361 # In Nit, the kind of a class cannot evolve in refinements
364 # The visibility of the class
365 # In Nit, the visibility of a class cannot evolve in refinements
366 var visibility
: MVisibility
368 init(intro_mmodule
: MModule, name
: String, arity
: Int, kind
: MClassKind, visibility
: MVisibility)
370 self.intro_mmodule
= intro_mmodule
374 self.visibility
= visibility
375 intro_mmodule
.intro_mclasses
.add
(self)
376 var model
= intro_mmodule
.model
377 model
.mclasses_by_name
.add_one
(name
, self)
378 model
.mclasses
.add
(self)
380 # Create the formal parameter types
382 var mparametertypes
= new Array[MParameterType]
383 for i
in [0..arity
[ do
384 var mparametertype
= new MParameterType(self, i
)
385 mparametertypes
.add
(mparametertype
)
387 var mclass_type
= new MGenericType(self, mparametertypes
)
388 self.mclass_type
= mclass_type
389 self.get_mtype_cache
.add
(mclass_type
)
391 self.mclass_type
= new MClassType(self)
395 redef fun model
do return intro_mmodule
.model
397 # All class definitions (introduction and refinements)
398 var mclassdefs
: Array[MClassDef] = new Array[MClassDef]
401 redef fun to_s
do return self.name
403 # The definition that introduced the class
404 # Warning: the introduction is the first `MClassDef` object associated
405 # to self. If self is just created without having any associated
406 # definition, this method will abort
409 assert has_a_first_definition
: not mclassdefs
.is_empty
410 return mclassdefs
.first
413 # Return the class `self` in the class hierarchy of the module `mmodule`.
415 # SEE: `MModule::flatten_mclass_hierarchy`
416 # REQUIRE: `mmodule.has_mclass(self)`
417 fun in_hierarchy
(mmodule
: MModule): POSetElement[MClass]
419 return mmodule
.flatten_mclass_hierarchy
[self]
422 # The principal static type of the class.
424 # For non-generic class, mclass_type is the only `MClassType` based
427 # For a generic class, the arguments are the formal parameters.
428 # i.e.: for the class Array[E:Object], the `mclass_type` is Array[E].
429 # If you want Array[Object] the see `MClassDef::bound_mtype`
431 # For generic classes, the mclass_type is also the way to get a formal
432 # generic parameter type.
434 # To get other types based on a generic class, see `get_mtype`.
436 # ENSURE: `mclass_type.mclass == self`
437 var mclass_type
: MClassType
439 # Return a generic type based on the class
440 # Is the class is not generic, then the result is `mclass_type`
442 # REQUIRE: `mtype_arguments.length == self.arity`
443 fun get_mtype
(mtype_arguments
: Array[MType]): MClassType
445 assert mtype_arguments
.length
== self.arity
446 if self.arity
== 0 then return self.mclass_type
447 for t
in self.get_mtype_cache
do
448 if t
.arguments
== mtype_arguments
then
452 var res
= new MGenericType(self, mtype_arguments
)
453 self.get_mtype_cache
.add res
457 private var get_mtype_cache
: Array[MGenericType] = new Array[MGenericType]
461 # A definition (an introduction or a refinement) of a class in a module
463 # A `MClassDef` is associated with an explicit (or almost) definition of a
464 # class. Unlike `MClass`, a `MClassDef` is a local definition that belong to
465 # a specific class and a specific module, and contains declarations like super-classes
468 # It is the class definitions that are the backbone of most things in the model:
469 # ClassDefs are defined with regard with other classdefs.
470 # Refinement and specialization are combined to produce a big poset called the `Model::mclassdef_hierarchy`.
472 # Moreover, the extension and the intention of types is defined by looking at the MClassDefs.
476 # The module where the definition is
479 # The associated `MClass`
482 # The bounded type associated to the mclassdef
484 # For a non-generic class, `bound_mtype` and `mclass.mclass_type`
488 # For the classdef Array[E: Object], the bound_mtype is Array[Object].
489 # If you want Array[E], then see `mclass.mclass_type`
491 # ENSURE: `bound_mtype.mclass == self.mclass`
492 var bound_mtype
: MClassType
494 # Name of each formal generic parameter (in order of declaration)
495 var parameter_names
: Array[String]
497 # The origin of the definition
498 var location
: Location
500 # Internal name combining the module and the class
501 # Example: "mymodule#MyClass"
502 redef var to_s
: String
504 init(mmodule
: MModule, bound_mtype
: MClassType, location
: Location, parameter_names
: Array[String])
506 assert bound_mtype
.mclass
.arity
== parameter_names
.length
507 self.bound_mtype
= bound_mtype
508 self.mmodule
= mmodule
509 self.mclass
= bound_mtype
.mclass
510 self.location
= location
511 mmodule
.mclassdefs
.add
(self)
512 mclass
.mclassdefs
.add
(self)
513 self.parameter_names
= parameter_names
514 self.to_s
= "{mmodule}#{mclass}"
517 # Actually the name of the `mclass`
518 redef fun name
do return mclass
.name
520 redef fun model
do return mmodule
.model
522 # All declared super-types
523 # FIXME: quite ugly but not better idea yet
524 var supertypes
: Array[MClassType] = new Array[MClassType]
526 # Register some super-types for the class (ie "super SomeType")
528 # The hierarchy must not already be set
529 # REQUIRE: `self.in_hierarchy == null`
530 fun set_supertypes
(supertypes
: Array[MClassType])
532 assert unique_invocation
: self.in_hierarchy
== null
533 var mmodule
= self.mmodule
534 var model
= mmodule
.model
535 var mtype
= self.bound_mtype
537 for supertype
in supertypes
do
538 self.supertypes
.add
(supertype
)
540 # Register in full_type_specialization_hierarchy
541 model
.full_mtype_specialization_hierarchy
.add_edge
(mtype
, supertype
)
542 # Register in intro_type_specialization_hierarchy
543 if mclass
.intro_mmodule
== mmodule
and supertype
.mclass
.intro_mmodule
== mmodule
then
544 model
.intro_mtype_specialization_hierarchy
.add_edge
(mtype
, supertype
)
550 # Collect the super-types (set by set_supertypes) to build the hierarchy
552 # This function can only invoked once by class
553 # REQUIRE: `self.in_hierarchy == null`
554 # ENSURE: `self.in_hierarchy != null`
557 assert unique_invocation
: self.in_hierarchy
== null
558 var model
= mmodule
.model
559 var res
= model
.mclassdef_hierarchy
.add_node
(self)
560 self.in_hierarchy
= res
561 var mtype
= self.bound_mtype
563 # Here we need to connect the mclassdef to its pairs in the mclassdef_hierarchy
564 # The simpliest way is to attach it to collect_mclassdefs
565 for mclassdef
in mtype
.collect_mclassdefs
(mmodule
) do
566 res
.poset
.add_edge
(self, mclassdef
)
570 # The view of the class definition in `mclassdef_hierarchy`
571 var in_hierarchy
: nullable POSetElement[MClassDef] = null
573 # Is the definition the one that introduced `mclass`?
574 fun is_intro
: Bool do return mclass
.intro
== self
576 # All properties introduced by the classdef
577 var intro_mproperties
: Array[MProperty] = new Array[MProperty]
579 # All property definitions in the class (introductions and redefinitions)
580 var mpropdefs
: Array[MPropDef] = new Array[MPropDef]
583 # A global static type
585 # MType are global to the model; it means that a `MType` is not bound to a
586 # specific `MModule`.
587 # This characteristic helps the reasoning about static types in a program
588 # since a single `MType` object always denote the same type.
590 # However, because a `MType` is global, it does not really have properties
591 # nor have subtypes to a hierarchy since the property and the class hierarchy
592 # depends of a module.
593 # Moreover, virtual types an formal generic parameter types also depends on
594 # a receiver to have sense.
596 # Therefore, most method of the types require a module and an anchor.
597 # The module is used to know what are the classes and the specialization
599 # The anchor is used to know what is the bound of the virtual types and formal
600 # generic parameter types.
602 # MType are not directly usable to get properties. See the `anchor_to` method
603 # and the `MClassType` class.
605 # FIXME: the order of the parameters is not the best. We mus pick on from:
606 # * foo(mmodule, anchor, othertype)
607 # * foo(othertype, anchor, mmodule)
608 # * foo(anchor, mmodule, othertype)
609 # * foo(othertype, mmodule, anchor)
613 redef fun name
do return to_s
615 # Return true if `self` is an subtype of `sup`.
616 # The typing is done using the standard typing policy of Nit.
618 # REQUIRE: `anchor == null implies not self.need_anchor and not sup.need_anchor`
619 # REQUIRE: `anchor != null implies self.can_resolve_for(anchor, null, mmodule) and sup.can_resolve_for(anchor, null, mmodule)`
620 fun is_subtype
(mmodule
: MModule, anchor
: nullable MClassType, sup
: MType): Bool
623 if sub
== sup
then return true
624 if anchor
== null then
625 assert not sub
.need_anchor
626 assert not sup
.need_anchor
628 assert sub
.can_resolve_for
(anchor
, null, mmodule
)
629 assert sup
.can_resolve_for
(anchor
, null, mmodule
)
632 # First, resolve the formal types to a common version in the receiver
633 # The trick here is that fixed formal type will be associed to the bound
634 # And unfixed formal types will be associed to a canonical formal type.
635 if sub
isa MParameterType or sub
isa MVirtualType then
636 assert anchor
!= null
637 sub
= sub
.resolve_for
(anchor
.mclass
.mclass_type
, anchor
, mmodule
, false)
639 if sup
isa MParameterType or sup
isa MVirtualType then
640 assert anchor
!= null
641 sup
= sup
.resolve_for
(anchor
.mclass
.mclass_type
, anchor
, mmodule
, false)
644 # Does `sup` accept null or not?
645 # Discard the nullable marker if it exists
646 var sup_accept_null
= false
647 if sup
isa MNullableType then
648 sup_accept_null
= true
650 else if sup
isa MNullType then
651 sup_accept_null
= true
654 # Can `sub` provide null or not?
655 # Thus we can match with `sup_accept_null`
656 # Also discard the nullable marker if it exists
657 if sub
isa MNullableType then
658 if not sup_accept_null
then return false
660 else if sub
isa MNullType then
661 return sup_accept_null
663 # Now the case of direct null and nullable is over.
665 # A unfixed formal type can only accept itself
666 if sup
isa MParameterType or sup
isa MVirtualType then
670 # If `sub` is a formal type, then it is accepted if its bound is accepted
671 if sub
isa MParameterType or sub
isa MVirtualType then
672 assert anchor
!= null
673 sub
= sub
.anchor_to
(mmodule
, anchor
)
675 # Manage the second layer of null/nullable
676 if sub
isa MNullableType then
677 if not sup_accept_null
then return false
679 else if sub
isa MNullType then
680 return sup_accept_null
684 assert sub
isa MClassType # It is the only remaining type
686 if sup
isa MNullType then
687 # `sup` accepts only null
691 assert sup
isa MClassType # It is the only remaining type
693 # Now both are MClassType, we need to dig
695 if sub
== sup
then return true
697 if anchor
== null then anchor
= sub
# UGLY: any anchor will work
698 var resolved_sub
= sub
.anchor_to
(mmodule
, anchor
)
699 var res
= resolved_sub
.collect_mclasses
(mmodule
).has
(sup
.mclass
)
700 if res
== false then return false
701 if not sup
isa MGenericType then return true
702 var sub2
= sub
.supertype_to
(mmodule
, anchor
, sup
.mclass
)
703 assert sub2
.mclass
== sup
.mclass
704 for i
in [0..sup
.mclass
.arity
[ do
705 var sub_arg
= sub2
.arguments
[i
]
706 var sup_arg
= sup
.arguments
[i
]
707 res
= sub_arg
.is_subtype
(mmodule
, anchor
, sup_arg
)
708 if res
== false then return false
713 # The base class type on which self is based
715 # This base type is used to get property (an internally to perform
716 # unsafe type comparison).
718 # Beware: some types (like null) are not based on a class thus this
721 # Basically, this function transform the virtual types and parameter
722 # types to their bounds.
726 # class B super A end
728 # class Y super X end
736 # Map[T,U] anchor_to H #-> Map[B,Y]
738 # Explanation of the example:
739 # In H, T is set to B, because "H super G[B]", and U is bound to Y,
740 # because "redef type U: Y". Therefore, Map[T, U] is bound to
743 # ENSURE: `not self.need_anchor implies result == self`
744 # ENSURE: `not result.need_anchor`
745 fun anchor_to
(mmodule
: MModule, anchor
: MClassType): MType
747 if not need_anchor
then return self
748 assert not anchor
.need_anchor
749 # Just resolve to the anchor and clear all the virtual types
750 var res
= self.resolve_for
(anchor
, null, mmodule
, true)
751 assert not res
.need_anchor
755 # Does `self` contain a virtual type or a formal generic parameter type?
756 # In order to remove those types, you usually want to use `anchor_to`.
757 fun need_anchor
: Bool do return true
759 # Return the supertype when adapted to a class.
761 # In Nit, for each super-class of a type, there is a equivalent super-type.
765 # class H[V] super G[V, Bool] end
766 # H[Int] supertype_to G #-> G[Int, Bool]
768 # REQUIRE: `super_mclass` is a super-class of `self`
769 # REQUIRE: `self.need_anchor implies anchor != null and self.can_resolve_for(anchor, null, mmodule)`
770 # ENSURE: `result.mclass = super_mclass`
771 fun supertype_to
(mmodule
: MModule, anchor
: nullable MClassType, super_mclass
: MClass): MClassType
773 if super_mclass
.arity
== 0 then return super_mclass
.mclass_type
774 if self isa MClassType and self.mclass
== super_mclass
then return self
776 if self.need_anchor
then
777 assert anchor
!= null
778 resolved_self
= self.anchor_to
(mmodule
, anchor
)
782 var supertypes
= resolved_self
.collect_mtypes
(mmodule
)
783 for supertype
in supertypes
do
784 if supertype
.mclass
== super_mclass
then
785 # FIXME: Here, we stop on the first goal. Should we check others and detect inconsistencies?
786 return supertype
.resolve_for
(self, anchor
, mmodule
, false)
792 # Replace formals generic types in self with resolved values in `mtype`
793 # If `cleanup_virtual` is true, then virtual types are also replaced
796 # This function returns self if `need_anchor` is false.
801 # class H[F] super G[F] end
804 # * Array[E].resolve_for(H[Int]) #-> Array[Int]
805 # * Array[E].resolve_for(G[Z], X[Int]) #-> Array[Z]
807 # Explanation of the example:
808 # * Array[E].need_anchor is true because there is a formal generic parameter type E
809 # * E makes sense for H[Int] because E is a formal parameter of G and H specialize G
810 # * Since "H[F] super G[F]", E is in fact F for H
811 # * More specifically, in H[Int], E is Int
812 # * So, in H[Int], Array[E] is Array[Int]
814 # This function is mainly used to inherit a signature.
815 # Because, unlike `anchor_to`, we do not want a full resolution of
816 # a type but only an adapted version of it.
821 # fun foo(e:E):E is abstract
823 # class B super A[Int] end
825 # The signature on foo is (e: E): E
826 # If we resolve the signature for B, we get (e:Int):Int
831 # fun foo(e:E) is abstract
835 # fun bar do a.foo(x) # <- x is here
838 # The first question is: is foo available on `a`?
840 # The static type of a is `A[Array[F]]`, that is an open type.
841 # in order to find a method `foo`, whe must look at a resolved type.
843 # A[Array[F]].anchor_to(B[nullable Object]) #-> A[Array[nullable Object]]
845 # the method `foo` exists in `A[Array[nullable Object]]`, therefore `foo` exists for `a`.
847 # The next question is: what is the accepted types for `x`?
849 # the signature of `foo` is `foo(e:E)`, thus we must resolve the type E
851 # E.resolve_for(A[Array[F]],B[nullable Object]) #-> Array[F]
853 # The resolution can be done because `E` make sense for the class A (see `can_resolve_for`)
855 # FIXME: the parameter `cleanup_virtual` is just a bad idea, but having
856 # two function instead of one seems also to be a bad idea.
858 # REQUIRE: `can_resolve_for(mtype, anchor, mmodule)`
859 # ENSURE: `not self.need_anchor implies result == self`
860 fun resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule, cleanup_virtual
: Bool): MType is abstract
862 # Can the type be resolved?
864 # In order to resolve open types, the formal types must make sence.
873 # * E.can_resolve_for(A[Int]) #-> true, E make sense in A
874 # * E.can_resolve_for(B[Int]) #-> false, E does not make sense in B
875 # * B[E].can_resolve_for(A[F], B[Object]) #-> true,
876 # B[E] is a red hearing only the E is important,
879 # REQUIRE: `anchor != null implies not anchor.need_anchor`
880 # REQUIRE: `mtype.need_anchor implies anchor != null and mtype.can_resolve_for(anchor, null, mmodule)`
881 # ENSURE: `not self.need_anchor implies result == true`
882 fun can_resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule): Bool is abstract
884 # Return the nullable version of the type
885 # If the type is already nullable then self is returned
886 fun as_nullable
: MType
888 var res
= self.as_nullable_cache
889 if res
!= null then return res
890 res
= new MNullableType(self)
891 self.as_nullable_cache
= res
895 # Return the not nullable version of the type
896 # Is the type is already not nullable, then self is returned.
898 # Note: this just remove the `nullable` notation, but the result can still contains null.
899 # For instance if `self isa MNullType` or self is a a formal type bounded by a nullable type.
900 fun as_notnullable
: MType
905 private var as_nullable_cache
: nullable MType = null
908 # The deph of the type seen as a tree.
915 # Formal types have a depth of 1.
921 # The length of the type seen as a tree.
928 # Formal types have a length of 1.
934 # Compute all the classdefs inherited/imported.
935 # The returned set contains:
936 # * the class definitions from `mmodule` and its imported modules
937 # * the class definitions of this type and its super-types
939 # This function is used mainly internally.
941 # REQUIRE: `not self.need_anchor`
942 fun collect_mclassdefs
(mmodule
: MModule): Set[MClassDef] is abstract
944 # Compute all the super-classes.
945 # This function is used mainly internally.
947 # REQUIRE: `not self.need_anchor`
948 fun collect_mclasses
(mmodule
: MModule): Set[MClass] is abstract
950 # Compute all the declared super-types.
951 # Super-types are returned as declared in the classdefs (verbatim).
952 # This function is used mainly internally.
954 # REQUIRE: `not self.need_anchor`
955 fun collect_mtypes
(mmodule
: MModule): Set[MClassType] is abstract
957 # Is the property in self for a given module
958 # This method does not filter visibility or whatever
960 # REQUIRE: `not self.need_anchor`
961 fun has_mproperty
(mmodule
: MModule, mproperty
: MProperty): Bool
963 assert not self.need_anchor
964 return self.collect_mclassdefs
(mmodule
).has
(mproperty
.intro_mclassdef
)
968 # A type based on a class.
970 # `MClassType` have properties (see `has_mproperty`).
974 # The associated class
977 redef fun model
do return self.mclass
.intro_mmodule
.model
979 private init(mclass
: MClass)
984 # The formal arguments of the type
985 # ENSURE: `result.length == self.mclass.arity`
986 var arguments
: Array[MType] = new Array[MType]
988 redef fun to_s
do return mclass
.to_s
990 redef fun need_anchor
do return false
992 redef fun anchor_to
(mmodule
: MModule, anchor
: MClassType): MClassType
994 return super.as(MClassType)
997 redef fun resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule, cleanup_virtual
: Bool): MClassType do return self
999 redef fun can_resolve_for
(mtype
, anchor
, mmodule
) do return true
1001 redef fun collect_mclassdefs
(mmodule
)
1003 assert not self.need_anchor
1004 var cache
= self.collect_mclassdefs_cache
1005 if not cache
.has_key
(mmodule
) then
1006 self.collect_things
(mmodule
)
1008 return cache
[mmodule
]
1011 redef fun collect_mclasses
(mmodule
)
1013 assert not self.need_anchor
1014 var cache
= self.collect_mclasses_cache
1015 if not cache
.has_key
(mmodule
) then
1016 self.collect_things
(mmodule
)
1018 return cache
[mmodule
]
1021 redef fun collect_mtypes
(mmodule
)
1023 assert not self.need_anchor
1024 var cache
= self.collect_mtypes_cache
1025 if not cache
.has_key
(mmodule
) then
1026 self.collect_things
(mmodule
)
1028 return cache
[mmodule
]
1031 # common implementation for `collect_mclassdefs`, `collect_mclasses`, and `collect_mtypes`.
1032 private fun collect_things
(mmodule
: MModule)
1034 var res
= new HashSet[MClassDef]
1035 var seen
= new HashSet[MClass]
1036 var types
= new HashSet[MClassType]
1037 seen
.add
(self.mclass
)
1038 var todo
= [self.mclass
]
1039 while not todo
.is_empty
do
1040 var mclass
= todo
.pop
1041 #print "process {mclass}"
1042 for mclassdef
in mclass
.mclassdefs
do
1043 if not mmodule
.in_importation
<= mclassdef
.mmodule
then continue
1044 #print " process {mclassdef}"
1046 for supertype
in mclassdef
.supertypes
do
1047 types
.add
(supertype
)
1048 var superclass
= supertype
.mclass
1049 if seen
.has
(superclass
) then continue
1050 #print " add {superclass}"
1051 seen
.add
(superclass
)
1052 todo
.add
(superclass
)
1056 collect_mclassdefs_cache
[mmodule
] = res
1057 collect_mclasses_cache
[mmodule
] = seen
1058 collect_mtypes_cache
[mmodule
] = types
1061 private var collect_mclassdefs_cache
: HashMap[MModule, Set[MClassDef]] = new HashMap[MModule, Set[MClassDef]]
1062 private var collect_mclasses_cache
: HashMap[MModule, Set[MClass]] = new HashMap[MModule, Set[MClass]]
1063 private var collect_mtypes_cache
: HashMap[MModule, Set[MClassType]] = new HashMap[MModule, Set[MClassType]]
1067 # A type based on a generic class.
1068 # A generic type a just a class with additional formal generic arguments.
1072 private init(mclass
: MClass, arguments
: Array[MType])
1075 assert self.mclass
.arity
== arguments
.length
1076 self.arguments
= arguments
1078 self.need_anchor
= false
1079 for t
in arguments
do
1080 if t
.need_anchor
then
1081 self.need_anchor
= true
1086 self.to_s
= "{mclass}[{arguments.join(", ")}]"
1089 # Recursively print the type of the arguments within brackets.
1090 # Example: `"Map[String, List[Int]]"`
1091 redef var to_s
: String
1093 redef var need_anchor
: Bool
1095 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1097 if not need_anchor
then return self
1098 assert can_resolve_for
(mtype
, anchor
, mmodule
)
1099 var types
= new Array[MType]
1100 for t
in arguments
do
1101 types
.add
(t
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
))
1103 return mclass
.get_mtype
(types
)
1106 redef fun can_resolve_for
(mtype
, anchor
, mmodule
)
1108 if not need_anchor
then return true
1109 for t
in arguments
do
1110 if not t
.can_resolve_for
(mtype
, anchor
, mmodule
) then return false
1119 for a
in self.arguments
do
1121 if d
> dmax
then dmax
= d
1129 for a
in self.arguments
do
1136 # A virtual formal type.
1140 # The property associated with the type.
1141 # Its the definitions of this property that determine the bound or the virtual type.
1142 var mproperty
: MProperty
1144 redef fun model
do return self.mproperty
.intro_mclassdef
.mmodule
.model
1146 # Lookup the bound for a given resolved_receiver
1147 # The result may be a other virtual type (or a parameter type)
1149 # The result is returned exactly as declared in the "type" property (verbatim).
1151 # In case of conflict, the method aborts.
1152 fun lookup_bound
(mmodule
: MModule, resolved_receiver
: MType): MType
1154 assert not resolved_receiver
.need_anchor
1155 var props
= self.mproperty
.lookup_definitions
(mmodule
, resolved_receiver
)
1156 if props
.is_empty
then
1158 else if props
.length
== 1 then
1159 return props
.first
.as(MVirtualTypeDef).bound
.as(not null)
1161 var types
= new ArraySet[MType]
1163 types
.add
(p
.as(MVirtualTypeDef).bound
.as(not null))
1165 if types
.length
== 1 then
1171 # Is the virtual type fixed for a given resolved_receiver?
1172 fun is_fixed
(mmodule
: MModule, resolved_receiver
: MType): Bool
1174 assert not resolved_receiver
.need_anchor
1175 var props
= self.mproperty
.lookup_definitions
(mmodule
, resolved_receiver
)
1176 if props
.is_empty
then
1180 if p
.as(MVirtualTypeDef).is_fixed
then return true
1185 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1187 assert can_resolve_for
(mtype
, anchor
, mmodule
)
1188 # self is a virtual type declared (or inherited) in mtype
1189 # The point of the function it to get the bound of the virtual type that make sense for mtype
1190 # But because mtype is maybe a virtual/formal type, we need to get a real receiver first
1191 #print "{class_name}: {self}/{mtype}/{anchor}?"
1192 var resolved_reciever
1193 if mtype
.need_anchor
then
1194 assert anchor
!= null
1195 resolved_reciever
= mtype
.resolve_for
(anchor
, null, mmodule
, true)
1197 resolved_reciever
= mtype
1199 # Now, we can get the bound
1200 var verbatim_bound
= lookup_bound
(mmodule
, resolved_reciever
)
1201 # The bound is exactly as declared in the "type" property, so we must resolve it again
1202 var res
= verbatim_bound
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1203 #print "{class_name}: {self}/{mtype}/{anchor} -> {self}/{resolved_reciever}/{anchor} -> {verbatim_bound}/{mtype}/{anchor} -> {res}"
1205 # What to return here? There is a bunch a special cases:
1206 # If 'cleanup_virtual' we must return the resolved type, since we cannot return self
1207 if cleanup_virtual
then return res
1208 # 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
1209 if resolved_reciever
isa MNullableType then resolved_reciever
= resolved_reciever
.mtype
1210 if resolved_reciever
.as(MClassType).mclass
.kind
== enum_kind
then return res
1211 # 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.
1212 if res
isa MVirtualType then return res
1213 # If we are final, just return the resolution
1214 if is_fixed
(mmodule
, resolved_reciever
) then return res
1215 # 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
1216 if res
isa MClassType and res
.mclass
.kind
== enum_kind
then return res
1217 # TODO: Add 'fixed' virtual type in the specification.
1218 # TODO: What if bound to a MParameterType?
1219 # Note that Nullable types can always be redefined by the non nullable version, so there is no specific case on it.
1221 # If anything apply, then `self' cannot be resolved, so return self
1225 redef fun can_resolve_for
(mtype
, anchor
, mmodule
)
1227 if mtype
.need_anchor
then
1228 assert anchor
!= null
1229 mtype
= mtype
.anchor_to
(mmodule
, anchor
)
1231 return mtype
.has_mproperty
(mmodule
, mproperty
)
1234 redef fun to_s
do return self.mproperty
.to_s
1236 init(mproperty
: MProperty)
1238 self.mproperty
= mproperty
1242 # The type associated the a formal parameter generic type of a class
1244 # Each parameter type is associated to a specific class.
1245 # It's mean that all refinements of a same class "share" the parameter type,
1246 # but that a generic subclass has its on parameter types.
1248 # However, in the sense of the meta-model, a parameter type of a class is
1249 # a valid type in a subclass. The "in the sense of the meta-model" is
1250 # important because, in the Nit language, the programmer cannot refers
1251 # directly to the parameter types of the super-classes.
1255 # fun e: E is abstract
1260 # In the class definition B[F], `F` is a valid type but `E` is not.
1261 # However, `self.e` is a valid method call, and the signature of `e` is
1264 # Note that parameter types are shared among class refinements.
1265 # Therefore parameter only have an internal name (see `to_s` for details).
1266 # TODO: Add a `name_for` to get better messages.
1267 class MParameterType
1270 # The generic class where the parameter belong
1273 redef fun model
do return self.mclass
.intro_mmodule
.model
1275 # The position of the parameter (0 for the first parameter)
1276 # FIXME: is `position` a better name?
1279 # Internal name of the parameter type
1280 # Names of parameter types changes in each class definition
1281 # Therefore, this method return an internal name.
1282 # Example: return "G#1" for the second parameter of the class G
1283 # FIXME: add a way to get the real name in a classdef
1284 redef fun to_s
do return "{mclass}#{rank}"
1286 # Resolve the bound for a given resolved_receiver
1287 # The result may be a other virtual type (or a parameter type)
1288 fun lookup_bound
(mmodule
: MModule, resolved_receiver
: MType): MType
1290 assert not resolved_receiver
.need_anchor
1291 var goalclass
= self.mclass
1292 var supertypes
= resolved_receiver
.collect_mtypes
(mmodule
)
1293 for t
in supertypes
do
1294 if t
.mclass
== goalclass
then
1295 # Yeah! c specialize goalclass with a "super `t'". So the question is what is the argument of f
1296 # FIXME: Here, we stop on the first goal. Should we check others and detect inconsistencies?
1297 var res
= t
.arguments
[self.rank
]
1304 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1306 assert can_resolve_for
(mtype
, anchor
, mmodule
)
1307 #print "{class_name}: {self}/{mtype}/{anchor}?"
1309 if mtype
isa MGenericType and mtype
.mclass
== self.mclass
then
1310 var res
= mtype
.arguments
[self.rank
]
1311 if anchor
!= null and res
.need_anchor
then
1312 # Maybe the result can be resolved more if are bound to a final class
1313 var r2
= res
.anchor_to
(mmodule
, anchor
)
1314 if r2
isa MClassType and r2
.mclass
.kind
== enum_kind
then return r2
1319 # self is a parameter type of mtype (or of a super-class of mtype)
1320 # The point of the function it to get the bound of the virtual type that make sense for mtype
1321 # But because mtype is maybe a virtual/formal type, we need to get a real receiver first
1322 # FIXME: What happend here is far from clear. Thus this part must be validated and clarified
1323 var resolved_receiver
1324 if mtype
.need_anchor
then
1325 assert anchor
!= null
1326 resolved_receiver
= mtype
.resolve_for
(anchor
.mclass
.mclass_type
, anchor
, mmodule
, true)
1328 resolved_receiver
= mtype
1330 if resolved_receiver
isa MNullableType then resolved_receiver
= resolved_receiver
.mtype
1331 if resolved_receiver
isa MParameterType then
1332 assert resolved_receiver
.mclass
== anchor
.mclass
1333 resolved_receiver
= anchor
.arguments
[resolved_receiver
.rank
]
1334 if resolved_receiver
isa MNullableType then resolved_receiver
= resolved_receiver
.mtype
1336 assert resolved_receiver
isa MClassType
1338 # Eh! The parameter is in the current class.
1339 # So we return the corresponding argument, no mater what!
1340 if resolved_receiver
.mclass
== self.mclass
then
1341 var res
= resolved_receiver
.arguments
[self.rank
]
1342 #print "{class_name}: {self}/{mtype}/{anchor} -> direct {res}"
1346 if resolved_receiver
.need_anchor
then
1347 assert anchor
!= null
1348 resolved_receiver
= resolved_receiver
.resolve_for
(anchor
, null, mmodule
, false)
1350 # Now, we can get the bound
1351 var verbatim_bound
= lookup_bound
(mmodule
, resolved_receiver
)
1352 # The bound is exactly as declared in the "type" property, so we must resolve it again
1353 var res
= verbatim_bound
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1355 #print "{class_name}: {self}/{mtype}/{anchor} -> indirect {res}"
1360 redef fun can_resolve_for
(mtype
, anchor
, mmodule
)
1362 if mtype
.need_anchor
then
1363 assert anchor
!= null
1364 mtype
= mtype
.anchor_to
(mmodule
, anchor
)
1366 return mtype
.collect_mclassdefs
(mmodule
).has
(mclass
.intro
)
1369 init(mclass
: MClass, rank
: Int)
1371 self.mclass
= mclass
1376 # A type prefixed with "nullable"
1380 # The base type of the nullable type
1383 redef fun model
do return self.mtype
.model
1388 self.to_s
= "nullable {mtype}"
1391 redef var to_s
: String
1393 redef fun need_anchor
do return mtype
.need_anchor
1394 redef fun as_nullable
do return self
1395 redef fun as_notnullable
do return mtype
1396 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1398 var res
= self.mtype
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1399 return res
.as_nullable
1402 redef fun can_resolve_for
(mtype
, anchor
, mmodule
)
1404 return self.mtype
.can_resolve_for
(mtype
, anchor
, mmodule
)
1407 redef fun depth
do return self.mtype
.depth
1409 redef fun length
do return self.mtype
.length
1411 redef fun collect_mclassdefs
(mmodule
)
1413 assert not self.need_anchor
1414 return self.mtype
.collect_mclassdefs
(mmodule
)
1417 redef fun collect_mclasses
(mmodule
)
1419 assert not self.need_anchor
1420 return self.mtype
.collect_mclasses
(mmodule
)
1423 redef fun collect_mtypes
(mmodule
)
1425 assert not self.need_anchor
1426 return self.mtype
.collect_mtypes
(mmodule
)
1430 # The type of the only value null
1432 # The is only one null type per model, see `MModel::null_type`.
1435 redef var model
: Model
1436 protected init(model
: Model)
1440 redef fun to_s
do return "null"
1441 redef fun as_nullable
do return self
1442 redef fun need_anchor
do return false
1443 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
) do return self
1444 redef fun can_resolve_for
(mtype
, anchor
, mmodule
) do return true
1446 redef fun collect_mclassdefs
(mmodule
) do return new HashSet[MClassDef]
1448 redef fun collect_mclasses
(mmodule
) do return new HashSet[MClass]
1450 redef fun collect_mtypes
(mmodule
) do return new HashSet[MClassType]
1453 # A signature of a method
1457 # The each parameter (in order)
1458 var mparameters
: Array[MParameter]
1460 # The return type (null for a procedure)
1461 var return_mtype
: nullable MType
1466 var t
= self.return_mtype
1467 if t
!= null then dmax
= t
.depth
1468 for p
in mparameters
do
1469 var d
= p
.mtype
.depth
1470 if d
> dmax
then dmax
= d
1478 var t
= self.return_mtype
1479 if t
!= null then res
+= t
.length
1480 for p
in mparameters
do
1481 res
+= p
.mtype
.length
1486 # REQUIRE: 1 <= mparameters.count p -> p.is_vararg
1487 init(mparameters
: Array[MParameter], return_mtype
: nullable MType)
1489 var vararg_rank
= -1
1490 for i
in [0..mparameters
.length
[ do
1491 var parameter
= mparameters
[i
]
1492 if parameter
.is_vararg
then
1493 assert vararg_rank
== -1
1497 self.mparameters
= mparameters
1498 self.return_mtype
= return_mtype
1499 self.vararg_rank
= vararg_rank
1502 # The rank of the ellipsis (`...`) for vararg (starting from 0).
1503 # value is -1 if there is no vararg.
1504 # Example: for "(a: Int, b: Bool..., c: Char)" #-> vararg_rank=1
1505 var vararg_rank
: Int
1507 # The number or parameters
1508 fun arity
: Int do return mparameters
.length
1512 var b
= new FlatBuffer
1513 if not mparameters
.is_empty
then
1515 for i
in [0..mparameters
.length
[ do
1516 var mparameter
= mparameters
[i
]
1517 if i
> 0 then b
.append
(", ")
1518 b
.append
(mparameter
.name
)
1520 b
.append
(mparameter
.mtype
.to_s
)
1521 if mparameter
.is_vararg
then
1527 var ret
= self.return_mtype
1535 redef fun resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule, cleanup_virtual
: Bool): MSignature
1537 var params
= new Array[MParameter]
1538 for p
in self.mparameters
do
1539 params
.add
(p
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
))
1541 var ret
= self.return_mtype
1543 ret
= ret
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1545 var res
= new MSignature(params
, ret
)
1550 # A parameter in a signature
1554 # The name of the parameter
1555 redef var name
: String
1557 # The static type of the parameter
1560 # Is the parameter a vararg?
1563 init(name
: String, mtype
: MType, is_vararg
: Bool) do
1566 self.is_vararg
= is_vararg
1572 return "{name}: {mtype}..."
1574 return "{name}: {mtype}"
1578 fun resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule, cleanup_virtual
: Bool): MParameter
1580 if not self.mtype
.need_anchor
then return self
1581 var newtype
= self.mtype
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1582 var res
= new MParameter(self.name
, newtype
, self.is_vararg
)
1586 redef fun model
do return mtype
.model
1589 # A service (global property) that generalize method, attribute, etc.
1591 # `MProperty` are global to the model; it means that a `MProperty` is not bound
1592 # to a specific `MModule` nor a specific `MClass`.
1594 # A MProperty gather definitions (see `mpropdefs`) ; one for the introduction
1595 # and the other in subclasses and in refinements.
1597 # A `MProperty` is used to denotes services in polymorphic way (ie. independent
1598 # of any dynamic type).
1599 # For instance, a call site "x.foo" is associated to a `MProperty`.
1600 abstract class MProperty
1603 # The associated MPropDef subclass.
1604 # The two specialization hierarchy are symmetric.
1605 type MPROPDEF: MPropDef
1607 # The classdef that introduce the property
1608 # While a property is not bound to a specific module, or class,
1609 # the introducing mclassdef is used for naming and visibility
1610 var intro_mclassdef
: MClassDef
1612 # The (short) name of the property
1613 redef var name
: String
1615 # The canonical name of the property
1616 # Example: "owner::my_module::MyClass::my_method"
1617 fun full_name
: String
1619 return "{self.intro_mclassdef.mmodule.full_name}::{self.intro_mclassdef.mclass.name}::{name}"
1622 # The visibility of the property
1623 var visibility
: MVisibility
1625 init(intro_mclassdef
: MClassDef, name
: String, visibility
: MVisibility)
1627 self.intro_mclassdef
= intro_mclassdef
1629 self.visibility
= visibility
1630 intro_mclassdef
.intro_mproperties
.add
(self)
1631 var model
= intro_mclassdef
.mmodule
.model
1632 model
.mproperties_by_name
.add_one
(name
, self)
1633 model
.mproperties
.add
(self)
1636 # All definitions of the property.
1637 # The first is the introduction,
1638 # The other are redefinitions (in refinements and in subclasses)
1639 var mpropdefs
: Array[MPROPDEF] = new Array[MPROPDEF]
1641 # The definition that introduced the property
1642 # Warning: the introduction is the first `MPropDef` object
1643 # associated to self. If self is just created without having any
1644 # associated definition, this method will abort
1645 fun intro
: MPROPDEF do return mpropdefs
.first
1647 redef fun model
do return intro
.model
1650 redef fun to_s
do return name
1652 # Return the most specific property definitions defined or inherited by a type.
1653 # The selection knows that refinement is stronger than specialization;
1654 # however, in case of conflict more than one property are returned.
1655 # If mtype does not know mproperty then an empty array is returned.
1657 # If you want the really most specific property, then look at `lookup_first_definition`
1658 fun lookup_definitions
(mmodule
: MModule, mtype
: MType): Array[MPROPDEF]
1660 assert not mtype
.need_anchor
1661 mtype
= mtype
.as_notnullable
1663 var cache
= self.lookup_definitions_cache
[mmodule
, mtype
]
1664 if cache
!= null then return cache
1666 #print "select prop {mproperty} for {mtype} in {self}"
1667 # First, select all candidates
1668 var candidates
= new Array[MPROPDEF]
1669 for mpropdef
in self.mpropdefs
do
1670 # If the definition is not imported by the module, then skip
1671 if not mmodule
.in_importation
<= mpropdef
.mclassdef
.mmodule
then continue
1672 # If the definition is not inherited by the type, then skip
1673 if not mtype
.is_subtype
(mmodule
, null, mpropdef
.mclassdef
.bound_mtype
) then continue
1675 candidates
.add
(mpropdef
)
1677 # Fast track for only one candidate
1678 if candidates
.length
<= 1 then
1679 self.lookup_definitions_cache
[mmodule
, mtype
] = candidates
1683 # Second, filter the most specific ones
1684 return select_most_specific
(mmodule
, candidates
)
1687 private var lookup_definitions_cache
: HashMap2[MModule, MType, Array[MPROPDEF]] = new HashMap2[MModule, MType, Array[MPROPDEF]]
1689 # Return the most specific property definitions inherited by a type.
1690 # The selection knows that refinement is stronger than specialization;
1691 # however, in case of conflict more than one property are returned.
1692 # If mtype does not know mproperty then an empty array is returned.
1694 # If you want the really most specific property, then look at `lookup_next_definition`
1696 # FIXME: Move to `MPropDef`?
1697 fun lookup_super_definitions
(mmodule
: MModule, mtype
: MType): Array[MPROPDEF]
1699 assert not mtype
.need_anchor
1700 mtype
= mtype
.as_notnullable
1702 # First, select all candidates
1703 var candidates
= new Array[MPROPDEF]
1704 for mpropdef
in self.mpropdefs
do
1705 # If the definition is not imported by the module, then skip
1706 if not mmodule
.in_importation
<= mpropdef
.mclassdef
.mmodule
then continue
1707 # If the definition is not inherited by the type, then skip
1708 if not mtype
.is_subtype
(mmodule
, null, mpropdef
.mclassdef
.bound_mtype
) then continue
1709 # If the definition is defined by the type, then skip (we want the super, so e skip the current)
1710 if mtype
== mpropdef
.mclassdef
.bound_mtype
and mmodule
== mpropdef
.mclassdef
.mmodule
then continue
1712 candidates
.add
(mpropdef
)
1714 # Fast track for only one candidate
1715 if candidates
.length
<= 1 then return candidates
1717 # Second, filter the most specific ones
1718 return select_most_specific
(mmodule
, candidates
)
1721 # Return an array containing olny the most specific property definitions
1722 # This is an helper function for `lookup_definitions` and `lookup_super_definitions`
1723 private fun select_most_specific
(mmodule
: MModule, candidates
: Array[MPROPDEF]): Array[MPROPDEF]
1725 var res
= new Array[MPROPDEF]
1726 for pd1
in candidates
do
1727 var cd1
= pd1
.mclassdef
1730 for pd2
in candidates
do
1731 if pd2
== pd1
then continue # do not compare with self!
1732 var cd2
= pd2
.mclassdef
1734 if c2
.mclass_type
== c1
.mclass_type
then
1735 if cd2
.mmodule
.in_importation
< cd1
.mmodule
then
1736 # cd2 refines cd1; therefore we skip pd1
1740 else if cd2
.bound_mtype
.is_subtype
(mmodule
, null, cd1
.bound_mtype
) and cd2
.bound_mtype
!= cd1
.bound_mtype
then
1741 # cd2 < cd1; therefore we skip pd1
1750 if res
.is_empty
then
1751 print
"All lost! {candidates.join(", ")}"
1752 # FIXME: should be abort!
1757 # Return the most specific definition in the linearization of `mtype`.
1759 # If you want to know the next properties in the linearization,
1760 # look at `MPropDef::lookup_next_definition`.
1762 # FIXME: the linearisation is still unspecified
1764 # REQUIRE: `not mtype.need_anchor`
1765 # REQUIRE: `mtype.has_mproperty(mmodule, self)`
1766 fun lookup_first_definition
(mmodule
: MModule, mtype
: MType): MPROPDEF
1768 assert mtype
.has_mproperty
(mmodule
, self)
1769 return lookup_all_definitions
(mmodule
, mtype
).first
1772 # Return all definitions in a linearisation order
1773 # Most speficic first, most general last
1774 fun lookup_all_definitions
(mmodule
: MModule, mtype
: MType): Array[MPROPDEF]
1776 assert not mtype
.need_anchor
1777 mtype
= mtype
.as_notnullable
1779 var cache
= self.lookup_all_definitions_cache
[mmodule
, mtype
]
1780 if cache
!= null then return cache
1782 #print "select prop {mproperty} for {mtype} in {self}"
1783 # First, select all candidates
1784 var candidates
= new Array[MPROPDEF]
1785 for mpropdef
in self.mpropdefs
do
1786 # If the definition is not imported by the module, then skip
1787 if not mmodule
.in_importation
<= mpropdef
.mclassdef
.mmodule
then continue
1788 # If the definition is not inherited by the type, then skip
1789 if not mtype
.is_subtype
(mmodule
, null, mpropdef
.mclassdef
.bound_mtype
) then continue
1791 candidates
.add
(mpropdef
)
1793 # Fast track for only one candidate
1794 if candidates
.length
<= 1 then
1795 self.lookup_all_definitions_cache
[mmodule
, mtype
] = candidates
1799 mmodule
.linearize_mpropdefs
(candidates
)
1800 candidates
= candidates
.reversed
1801 self.lookup_all_definitions_cache
[mmodule
, mtype
] = candidates
1805 private var lookup_all_definitions_cache
: HashMap2[MModule, MType, Array[MPROPDEF]] = new HashMap2[MModule, MType, Array[MPROPDEF]]
1812 redef type MPROPDEF: MMethodDef
1814 init(intro_mclassdef
: MClassDef, name
: String, visibility
: MVisibility)
1819 # Is the property defined at the top_level of the module?
1820 # Currently such a property are stored in `Object`
1821 var is_toplevel
: Bool writable = false
1823 # Is the property a constructor?
1824 # Warning, this property can be inherited by subclasses with or without being a constructor
1825 # therefore, you should use `is_init_for` the verify if the property is a legal constructor for a given class
1826 var is_init
: Bool writable = false
1828 # The constructor is a (the) root init with empty signature but a set of initializers
1829 var is_root_init
: Bool writable = false
1831 # The the property a 'new' contructor?
1832 var is_new
: Bool writable = false
1834 # Is the property a legal constructor for a given class?
1835 # As usual, visibility is not considered.
1836 # FIXME not implemented
1837 fun is_init_for
(mclass
: MClass): Bool
1843 # A global attribute
1847 redef type MPROPDEF: MAttributeDef
1849 init(intro_mclassdef
: MClassDef, name
: String, visibility
: MVisibility)
1855 # A global virtual type
1856 class MVirtualTypeProp
1859 redef type MPROPDEF: MVirtualTypeDef
1861 init(intro_mclassdef
: MClassDef, name
: String, visibility
: MVisibility)
1866 # The formal type associated to the virtual type property
1867 var mvirtualtype
: MVirtualType = new MVirtualType(self)
1870 # A definition of a property (local property)
1872 # Unlike `MProperty`, a `MPropDef` is a local definition that belong to a
1873 # specific class definition (which belong to a specific module)
1874 abstract class MPropDef
1877 # The associated `MProperty` subclass.
1878 # the two specialization hierarchy are symmetric
1879 type MPROPERTY: MProperty
1882 type MPROPDEF: MPropDef
1884 # The origin of the definition
1885 var location
: Location
1887 # The class definition where the property definition is
1888 var mclassdef
: MClassDef
1890 # The associated global property
1891 var mproperty
: MPROPERTY
1893 init(mclassdef
: MClassDef, mproperty
: MPROPERTY, location
: Location)
1895 self.mclassdef
= mclassdef
1896 self.mproperty
= mproperty
1897 self.location
= location
1898 mclassdef
.mpropdefs
.add
(self)
1899 mproperty
.mpropdefs
.add
(self)
1900 self.to_s
= "{mclassdef}#{mproperty}"
1903 # Actually the name of the `mproperty`
1904 redef fun name
do return mproperty
.name
1906 redef fun model
do return mclassdef
.model
1908 # Internal name combining the module, the class and the property
1909 # Example: "mymodule#MyClass#mymethod"
1910 redef var to_s
: String
1912 # Is self the definition that introduce the property?
1913 fun is_intro
: Bool do return mproperty
.intro
== self
1915 # Return the next definition in linearization of `mtype`.
1917 # This method is used to determine what method is called by a super.
1919 # REQUIRE: `not mtype.need_anchor`
1920 fun lookup_next_definition
(mmodule
: MModule, mtype
: MType): MPROPDEF
1922 assert not mtype
.need_anchor
1924 var mpropdefs
= self.mproperty
.lookup_all_definitions
(mmodule
, mtype
)
1925 var i
= mpropdefs
.iterator
1926 while i
.is_ok
and i
.item
!= self do i
.next
1927 assert has_property
: i
.is_ok
1929 assert has_next_property
: i
.is_ok
1934 # A local definition of a method
1938 redef type MPROPERTY: MMethod
1939 redef type MPROPDEF: MMethodDef
1941 init(mclassdef
: MClassDef, mproperty
: MPROPERTY, location
: Location)
1946 # The signature attached to the property definition
1947 var msignature
: nullable MSignature writable = null
1949 # The signature attached to the `new` call on a root-init
1950 # This is a concatenation of the signatures of the initializers
1952 # REQUIRE `mproperty.is_root_init == (new_msignature != null)`
1953 var new_msignature
: nullable MSignature writable = null
1955 # List of initialisers to call in root-inits
1957 # They could be setters or attributes
1959 # REQUIRE `mproperty.is_root_init == (new_msignature != null)`
1960 var initializers
= new Array[MProperty]
1962 # Is the method definition abstract?
1963 var is_abstract
: Bool writable = false
1965 # Is the method definition intern?
1966 var is_intern
writable = false
1968 # Is the method definition extern?
1969 var is_extern
writable = false
1972 # A local definition of an attribute
1976 redef type MPROPERTY: MAttribute
1977 redef type MPROPDEF: MAttributeDef
1979 init(mclassdef
: MClassDef, mproperty
: MPROPERTY, location
: Location)
1984 # The static type of the attribute
1985 var static_mtype
: nullable MType writable = null
1988 # A local definition of a virtual type
1989 class MVirtualTypeDef
1992 redef type MPROPERTY: MVirtualTypeProp
1993 redef type MPROPDEF: MVirtualTypeDef
1995 init(mclassdef
: MClassDef, mproperty
: MPROPERTY, location
: Location)
2000 # The bound of the virtual type
2001 var bound
: nullable MType writable = null
2003 # Is the bound fixed?
2004 var is_fixed
writable = false
2011 # * `interface_kind`
2015 # Note this class is basically an enum.
2016 # FIXME: use a real enum once user-defined enums are available
2018 redef var to_s
: String
2020 # Is a constructor required?
2022 private init(s
: String, need_init
: Bool)
2025 self.need_init
= need_init
2028 # Can a class of kind `self` specializes a class of kine `other`?
2029 fun can_specialize
(other
: MClassKind): Bool
2031 if other
== interface_kind
then return true # everybody can specialize interfaces
2032 if self == interface_kind
or self == enum_kind
then
2033 # no other case for interfaces
2035 else if self == extern_kind
then
2036 # only compatible with themselve
2037 return self == other
2038 else if other
== enum_kind
or other
== extern_kind
then
2039 # abstract_kind and concrete_kind are incompatible
2042 # remain only abstract_kind and concrete_kind
2047 fun abstract_kind
: MClassKind do return once
new MClassKind("abstract class", true)
2048 fun concrete_kind
: MClassKind do return once
new MClassKind("class", true)
2049 fun interface_kind
: MClassKind do return once
new MClassKind("interface", false)
2050 fun enum_kind
: MClassKind do return once
new MClassKind("enum", false)
2051 fun extern_kind
: MClassKind do return once
new MClassKind("extern class", false)