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
= new Array[MClass]
37 # All known properties
38 var mproperties
= 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
= 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
= 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
= new POSet[MClassType]
66 # Collections of classes grouped by their short name
67 private var mclasses_by_name
= 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
= 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
= 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
= new Array[MClass]
139 # All the class definitions of the module
140 # (introduction and refinement)
141 var mclassdefs
= 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 linearization 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 linearization 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 linearization 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 type `Pointer`, super class to all extern classes
218 var pointer_type
: MClassType = self.get_primitive_class
("Pointer").mclass_type
is lazy
220 # The primitive type `Bool`
221 fun bool_type
: MClassType
223 var res
= self.bool_type_cache
224 if res
!= null then return res
225 res
= self.get_primitive_class
("Bool").mclass_type
226 self.bool_type_cache
= res
230 private var bool_type_cache
: nullable MClassType
232 # The primitive type `Sys`, the main type of the program, if any
233 fun sys_type
: nullable MClassType
235 var clas
= self.model
.get_mclasses_by_name
("Sys")
236 if clas
== null then return null
237 return get_primitive_class
("Sys").mclass_type
240 # The primitive type `Finalizable`
241 # Used to tag classes that need to be finalized.
242 fun finalizable_type
: nullable MClassType
244 var clas
= self.model
.get_mclasses_by_name
("Finalizable")
245 if clas
== null then return null
246 return get_primitive_class
("Finalizable").mclass_type
249 # Force to get the primitive class named `name` or abort
250 fun get_primitive_class
(name
: String): MClass
252 var cla
= self.model
.get_mclasses_by_name
(name
)
254 if name
== "Bool" then
255 var c
= new MClass(self, name
, null, enum_kind
, public_visibility
)
256 var cladef
= new MClassDef(self, c
.mclass_type
, new Location(null, 0,0,0,0))
259 print
("Fatal Error: no primitive class {name}")
262 if cla
.length
!= 1 then
263 var msg
= "Fatal Error: more than one primitive class {name}:"
264 for c
in cla
do msg
+= " {c.full_name}"
271 # Try to get the primitive method named `name` on the type `recv`
272 fun try_get_primitive_method
(name
: String, recv
: MClass): nullable MMethod
274 var props
= self.model
.get_mproperties_by_name
(name
)
275 if props
== null then return null
276 var res
: nullable MMethod = null
277 for mprop
in props
do
278 assert mprop
isa MMethod
279 var intro
= mprop
.intro_mclassdef
280 for mclassdef
in recv
.mclassdefs
do
281 if not self.in_importation
.greaters
.has
(mclassdef
.mmodule
) then continue
282 if not mclassdef
.in_hierarchy
.greaters
.has
(intro
) then continue
285 else if res
!= mprop
then
286 print
("Fatal Error: ambigous property name '{name}'; conflict between {mprop.full_name} and {res.full_name}")
295 private class MClassDefSorter
297 redef type COMPARED: MClassDef
299 redef fun compare
(a
, b
)
303 if ca
!= cb
then return mmodule
.flatten_mclass_hierarchy
.compare
(ca
, cb
)
304 return mmodule
.model
.mclassdef_hierarchy
.compare
(a
, b
)
308 private class MPropDefSorter
310 redef type COMPARED: MPropDef
312 redef fun compare
(pa
, pb
)
318 if ca
!= cb
then return mmodule
.flatten_mclass_hierarchy
.compare
(ca
, cb
)
319 return mmodule
.model
.mclassdef_hierarchy
.compare
(a
, b
)
325 # `MClass` are global to the model; it means that a `MClass` is not bound to a
326 # specific `MModule`.
328 # This characteristic helps the reasoning about classes in a program since a
329 # single `MClass` object always denote the same class.
331 # The drawback is that classes (`MClass`) contain almost nothing by themselves.
332 # These do not really have properties nor belong to a hierarchy since the property and the
333 # hierarchy of a class depends of the refinement in the modules.
335 # Most services on classes require the precision of a module, and no one can asks what are
336 # the super-classes of a class nor what are properties of a class without precising what is
337 # the module considered.
339 # For instance, during the typing of a source-file, the module considered is the module of the file.
340 # eg. the question *is the method `foo` exists in the class `Bar`?* must be reformulated into
341 # *is the method `foo` exists in the class `Bar` in the current module?*
343 # During some global analysis, the module considered may be the main module of the program.
347 # The module that introduce the class
348 # While classes are not bound to a specific module,
349 # the introducing module is used for naming an visibility
350 var intro_mmodule
: MModule
352 # The short name of the class
353 # In Nit, the name of a class cannot evolve in refinements
354 redef var name
: String
356 # The canonical name of the class
357 # Example: `"owner::module::MyClass"`
358 fun full_name
: String
360 return "{self.intro_mmodule.full_name}::{name}"
363 # The number of generic formal parameters
364 # 0 if the class is not generic
365 var arity
: Int is noinit
367 # Each generic formal parameters in order.
368 # is empty if the class is not generic
369 var mparameters
= new Array[MParameterType]
371 protected fun setup_parameter_names
(parameter_names
: nullable Array[String]) is
374 if parameter_names
== null then
377 self.arity
= parameter_names
.length
380 # Create the formal parameter types
382 assert parameter_names
!= null
383 var mparametertypes
= new Array[MParameterType]
384 for i
in [0..arity
[ do
385 var mparametertype
= new MParameterType(self, i
, parameter_names
[i
])
386 mparametertypes
.add
(mparametertype
)
388 self.mparameters
= mparametertypes
389 var mclass_type
= new MGenericType(self, mparametertypes
)
390 self.mclass_type
= mclass_type
391 self.get_mtype_cache
[mparametertypes
] = mclass_type
393 self.mclass_type
= new MClassType(self)
397 # The kind of the class (interface, abstract class, etc.)
398 # In Nit, the kind of a class cannot evolve in refinements
401 # The visibility of the class
402 # In Nit, the visibility of a class cannot evolve in refinements
403 var visibility
: MVisibility
407 intro_mmodule
.intro_mclasses
.add
(self)
408 var model
= intro_mmodule
.model
409 model
.mclasses_by_name
.add_one
(name
, self)
410 model
.mclasses
.add
(self)
413 redef fun model
do return intro_mmodule
.model
415 # All class definitions (introduction and refinements)
416 var mclassdefs
= new Array[MClassDef]
419 redef fun to_s
do return self.name
421 # The definition that introduces the class.
423 # Warning: such a definition may not exist in the early life of the object.
424 # In this case, the method will abort.
425 var intro
: MClassDef is noinit
427 # Return the class `self` in the class hierarchy of the module `mmodule`.
429 # SEE: `MModule::flatten_mclass_hierarchy`
430 # REQUIRE: `mmodule.has_mclass(self)`
431 fun in_hierarchy
(mmodule
: MModule): POSetElement[MClass]
433 return mmodule
.flatten_mclass_hierarchy
[self]
436 # The principal static type of the class.
438 # For non-generic class, mclass_type is the only `MClassType` based
441 # For a generic class, the arguments are the formal parameters.
442 # i.e.: for the class Array[E:Object], the `mclass_type` is Array[E].
443 # If you want Array[Object] the see `MClassDef::bound_mtype`
445 # For generic classes, the mclass_type is also the way to get a formal
446 # generic parameter type.
448 # To get other types based on a generic class, see `get_mtype`.
450 # ENSURE: `mclass_type.mclass == self`
451 var mclass_type
: MClassType is noinit
453 # Return a generic type based on the class
454 # Is the class is not generic, then the result is `mclass_type`
456 # REQUIRE: `mtype_arguments.length == self.arity`
457 fun get_mtype
(mtype_arguments
: Array[MType]): MClassType
459 assert mtype_arguments
.length
== self.arity
460 if self.arity
== 0 then return self.mclass_type
461 var res
= get_mtype_cache
.get_or_null
(mtype_arguments
)
462 if res
!= null then return res
463 res
= new MGenericType(self, mtype_arguments
)
464 self.get_mtype_cache
[mtype_arguments
.to_a
] = res
468 private var get_mtype_cache
= new HashMap[Array[MType], MGenericType]
472 # A definition (an introduction or a refinement) of a class in a module
474 # A `MClassDef` is associated with an explicit (or almost) definition of a
475 # class. Unlike `MClass`, a `MClassDef` is a local definition that belong to
476 # a specific class and a specific module, and contains declarations like super-classes
479 # It is the class definitions that are the backbone of most things in the model:
480 # ClassDefs are defined with regard with other classdefs.
481 # Refinement and specialization are combined to produce a big poset called the `Model::mclassdef_hierarchy`.
483 # Moreover, the extension and the intention of types is defined by looking at the MClassDefs.
487 # The module where the definition is
490 # The associated `MClass`
491 var mclass
: MClass is noinit
493 # The bounded type associated to the mclassdef
495 # For a non-generic class, `bound_mtype` and `mclass.mclass_type`
499 # For the classdef Array[E: Object], the bound_mtype is Array[Object].
500 # If you want Array[E], then see `mclass.mclass_type`
502 # ENSURE: `bound_mtype.mclass == self.mclass`
503 var bound_mtype
: MClassType
505 # The origin of the definition
506 var location
: Location
508 # Internal name combining the module and the class
509 # Example: "mymodule#MyClass"
510 redef var to_s
: String is noinit
514 self.mclass
= bound_mtype
.mclass
515 mmodule
.mclassdefs
.add
(self)
516 mclass
.mclassdefs
.add
(self)
517 if mclass
.intro_mmodule
== mmodule
then
518 assert not isset mclass
._intro
521 self.to_s
= "{mmodule}#{mclass}"
524 # Actually the name of the `mclass`
525 redef fun name
do return mclass
.name
527 redef fun model
do return mmodule
.model
529 # All declared super-types
530 # FIXME: quite ugly but not better idea yet
531 var supertypes
= new Array[MClassType]
533 # Register some super-types for the class (ie "super SomeType")
535 # The hierarchy must not already be set
536 # REQUIRE: `self.in_hierarchy == null`
537 fun set_supertypes
(supertypes
: Array[MClassType])
539 assert unique_invocation
: self.in_hierarchy
== null
540 var mmodule
= self.mmodule
541 var model
= mmodule
.model
542 var mtype
= self.bound_mtype
544 for supertype
in supertypes
do
545 self.supertypes
.add
(supertype
)
547 # Register in full_type_specialization_hierarchy
548 model
.full_mtype_specialization_hierarchy
.add_edge
(mtype
, supertype
)
549 # Register in intro_type_specialization_hierarchy
550 if mclass
.intro_mmodule
== mmodule
and supertype
.mclass
.intro_mmodule
== mmodule
then
551 model
.intro_mtype_specialization_hierarchy
.add_edge
(mtype
, supertype
)
557 # Collect the super-types (set by set_supertypes) to build the hierarchy
559 # This function can only invoked once by class
560 # REQUIRE: `self.in_hierarchy == null`
561 # ENSURE: `self.in_hierarchy != null`
564 assert unique_invocation
: self.in_hierarchy
== null
565 var model
= mmodule
.model
566 var res
= model
.mclassdef_hierarchy
.add_node
(self)
567 self.in_hierarchy
= res
568 var mtype
= self.bound_mtype
570 # Here we need to connect the mclassdef to its pairs in the mclassdef_hierarchy
571 # The simpliest way is to attach it to collect_mclassdefs
572 for mclassdef
in mtype
.collect_mclassdefs
(mmodule
) do
573 res
.poset
.add_edge
(self, mclassdef
)
577 # The view of the class definition in `mclassdef_hierarchy`
578 var in_hierarchy
: nullable POSetElement[MClassDef] = null
580 # Is the definition the one that introduced `mclass`?
581 fun is_intro
: Bool do return mclass
.intro
== self
583 # All properties introduced by the classdef
584 var intro_mproperties
= new Array[MProperty]
586 # All property definitions in the class (introductions and redefinitions)
587 var mpropdefs
= new Array[MPropDef]
590 # A global static type
592 # MType are global to the model; it means that a `MType` is not bound to a
593 # specific `MModule`.
594 # This characteristic helps the reasoning about static types in a program
595 # since a single `MType` object always denote the same type.
597 # However, because a `MType` is global, it does not really have properties
598 # nor have subtypes to a hierarchy since the property and the class hierarchy
599 # depends of a module.
600 # Moreover, virtual types an formal generic parameter types also depends on
601 # a receiver to have sense.
603 # Therefore, most method of the types require a module and an anchor.
604 # The module is used to know what are the classes and the specialization
606 # The anchor is used to know what is the bound of the virtual types and formal
607 # generic parameter types.
609 # MType are not directly usable to get properties. See the `anchor_to` method
610 # and the `MClassType` class.
612 # FIXME: the order of the parameters is not the best. We mus pick on from:
613 # * foo(mmodule, anchor, othertype)
614 # * foo(othertype, anchor, mmodule)
615 # * foo(anchor, mmodule, othertype)
616 # * foo(othertype, mmodule, anchor)
620 redef fun name
do return to_s
622 # Return true if `self` is an subtype of `sup`.
623 # The typing is done using the standard typing policy of Nit.
625 # REQUIRE: `anchor == null implies not self.need_anchor and not sup.need_anchor`
626 # REQUIRE: `anchor != null implies self.can_resolve_for(anchor, null, mmodule) and sup.can_resolve_for(anchor, null, mmodule)`
627 fun is_subtype
(mmodule
: MModule, anchor
: nullable MClassType, sup
: MType): Bool
630 if sub
== sup
then return true
631 if anchor
== null then
632 assert not sub
.need_anchor
633 assert not sup
.need_anchor
635 assert sub
.can_resolve_for
(anchor
, null, mmodule
)
636 assert sup
.can_resolve_for
(anchor
, null, mmodule
)
639 # First, resolve the formal types to a common version in the receiver
640 # The trick here is that fixed formal type will be associated to the bound
641 # And unfixed formal types will be associated to a canonical formal type.
642 if sub
isa MParameterType or sub
isa MVirtualType then
643 assert anchor
!= null
644 sub
= sub
.resolve_for
(anchor
.mclass
.mclass_type
, anchor
, mmodule
, false)
646 if sup
isa MParameterType or sup
isa MVirtualType then
647 assert anchor
!= null
648 sup
= sup
.resolve_for
(anchor
.mclass
.mclass_type
, anchor
, mmodule
, false)
651 # Does `sup` accept null or not?
652 # Discard the nullable marker if it exists
653 var sup_accept_null
= false
654 if sup
isa MNullableType then
655 sup_accept_null
= true
657 else if sup
isa MNullType then
658 sup_accept_null
= true
661 # Can `sub` provide null or not?
662 # Thus we can match with `sup_accept_null`
663 # Also discard the nullable marker if it exists
664 if sub
isa MNullableType then
665 if not sup_accept_null
then return false
667 else if sub
isa MNullType then
668 return sup_accept_null
670 # Now the case of direct null and nullable is over.
672 # A unfixed formal type can only accept itself
673 if sup
isa MParameterType or sup
isa MVirtualType then
677 # If `sub` is a formal type, then it is accepted if its bound is accepted
678 if sub
isa MParameterType or sub
isa MVirtualType then
679 assert anchor
!= null
680 sub
= sub
.anchor_to
(mmodule
, anchor
)
682 # Manage the second layer of null/nullable
683 if sub
isa MNullableType then
684 if not sup_accept_null
then return false
686 else if sub
isa MNullType then
687 return sup_accept_null
691 assert sub
isa MClassType # It is the only remaining type
693 if sup
isa MNullType then
694 # `sup` accepts only null
698 assert sup
isa MClassType # It is the only remaining type
700 # Now both are MClassType, we need to dig
702 if sub
== sup
then return true
704 if anchor
== null then anchor
= sub
# UGLY: any anchor will work
705 var resolved_sub
= sub
.anchor_to
(mmodule
, anchor
)
706 var res
= resolved_sub
.collect_mclasses
(mmodule
).has
(sup
.mclass
)
707 if res
== false then return false
708 if not sup
isa MGenericType then return true
709 var sub2
= sub
.supertype_to
(mmodule
, anchor
, sup
.mclass
)
710 assert sub2
.mclass
== sup
.mclass
711 for i
in [0..sup
.mclass
.arity
[ do
712 var sub_arg
= sub2
.arguments
[i
]
713 var sup_arg
= sup
.arguments
[i
]
714 res
= sub_arg
.is_subtype
(mmodule
, anchor
, sup_arg
)
715 if res
== false then return false
720 # The base class type on which self is based
722 # This base type is used to get property (an internally to perform
723 # unsafe type comparison).
725 # Beware: some types (like null) are not based on a class thus this
728 # Basically, this function transform the virtual types and parameter
729 # types to their bounds.
734 # class B super A end
736 # class Y super X end
745 # Map[T,U] anchor_to H #-> Map[B,Y]
747 # Explanation of the example:
748 # In H, T is set to B, because "H super G[B]", and U is bound to Y,
749 # because "redef type U: Y". Therefore, Map[T, U] is bound to
752 # ENSURE: `not self.need_anchor implies result == self`
753 # ENSURE: `not result.need_anchor`
754 fun anchor_to
(mmodule
: MModule, anchor
: MClassType): MType
756 if not need_anchor
then return self
757 assert not anchor
.need_anchor
758 # Just resolve to the anchor and clear all the virtual types
759 var res
= self.resolve_for
(anchor
, null, mmodule
, true)
760 assert not res
.need_anchor
764 # Does `self` contain a virtual type or a formal generic parameter type?
765 # In order to remove those types, you usually want to use `anchor_to`.
766 fun need_anchor
: Bool do return true
768 # Return the supertype when adapted to a class.
770 # In Nit, for each super-class of a type, there is a equivalent super-type.
776 # class H[V] super G[V, Bool] end
778 # H[Int] supertype_to G #-> G[Int, Bool]
781 # REQUIRE: `super_mclass` is a super-class of `self`
782 # REQUIRE: `self.need_anchor implies anchor != null and self.can_resolve_for(anchor, null, mmodule)`
783 # ENSURE: `result.mclass = super_mclass`
784 fun supertype_to
(mmodule
: MModule, anchor
: nullable MClassType, super_mclass
: MClass): MClassType
786 if super_mclass
.arity
== 0 then return super_mclass
.mclass_type
787 if self isa MClassType and self.mclass
== super_mclass
then return self
789 if self.need_anchor
then
790 assert anchor
!= null
791 resolved_self
= self.anchor_to
(mmodule
, anchor
)
795 var supertypes
= resolved_self
.collect_mtypes
(mmodule
)
796 for supertype
in supertypes
do
797 if supertype
.mclass
== super_mclass
then
798 # FIXME: Here, we stop on the first goal. Should we check others and detect inconsistencies?
799 return supertype
.resolve_for
(self, anchor
, mmodule
, false)
805 # Replace formals generic types in self with resolved values in `mtype`
806 # If `cleanup_virtual` is true, then virtual types are also replaced
809 # This function returns self if `need_anchor` is false.
815 # class H[F] super G[F] end
819 # * Array[E].resolve_for(H[Int]) #-> Array[Int]
820 # * Array[E].resolve_for(G[Z], X[Int]) #-> Array[Z]
822 # Explanation of the example:
823 # * Array[E].need_anchor is true because there is a formal generic parameter type E
824 # * E makes sense for H[Int] because E is a formal parameter of G and H specialize G
825 # * Since "H[F] super G[F]", E is in fact F for H
826 # * More specifically, in H[Int], E is Int
827 # * So, in H[Int], Array[E] is Array[Int]
829 # This function is mainly used to inherit a signature.
830 # Because, unlike `anchor_to`, we do not want a full resolution of
831 # a type but only an adapted version of it.
837 # fun foo(e:E):E is abstract
839 # class B super A[Int] end
842 # The signature on foo is (e: E): E
843 # If we resolve the signature for B, we get (e:Int):Int
849 # fun foo(e:E):E is abstract
853 # fun bar do a.foo(x) # <- x is here
857 # The first question is: is foo available on `a`?
859 # The static type of a is `A[Array[F]]`, that is an open type.
860 # in order to find a method `foo`, whe must look at a resolved type.
862 # A[Array[F]].anchor_to(C[nullable Object]) #-> A[Array[nullable Object]]
864 # the method `foo` exists in `A[Array[nullable Object]]`, therefore `foo` exists for `a`.
866 # The next question is: what is the accepted types for `x`?
868 # the signature of `foo` is `foo(e:E)`, thus we must resolve the type E
870 # E.resolve_for(A[Array[F]],C[nullable Object]) #-> Array[F]
872 # The resolution can be done because `E` make sense for the class A (see `can_resolve_for`)
874 # FIXME: the parameter `cleanup_virtual` is just a bad idea, but having
875 # two function instead of one seems also to be a bad idea.
877 # REQUIRE: `can_resolve_for(mtype, anchor, mmodule)`
878 # ENSURE: `not self.need_anchor implies result == self`
879 fun resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule, cleanup_virtual
: Bool): MType is abstract
881 # Can the type be resolved?
883 # In order to resolve open types, the formal types must make sence.
893 # E.can_resolve_for(A[Int]) #-> true, E make sense in A
895 # E.can_resolve_for(B[Int]) #-> false, E does not make sense in B
897 # B[E].can_resolve_for(A[F], B[Object]) #-> true,
898 # # B[E] is a red hearing only the E is important,
899 # # E make sense in A
902 # REQUIRE: `anchor != null implies not anchor.need_anchor`
903 # REQUIRE: `mtype.need_anchor implies anchor != null and mtype.can_resolve_for(anchor, null, mmodule)`
904 # ENSURE: `not self.need_anchor implies result == true`
905 fun can_resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule): Bool is abstract
907 # Return the nullable version of the type
908 # If the type is already nullable then self is returned
909 fun as_nullable
: MType
911 var res
= self.as_nullable_cache
912 if res
!= null then return res
913 res
= new MNullableType(self)
914 self.as_nullable_cache
= res
918 # Return the not nullable version of the type
919 # Is the type is already not nullable, then self is returned.
921 # Note: this just remove the `nullable` notation, but the result can still contains null.
922 # For instance if `self isa MNullType` or self is a formal type bounded by a nullable type.
923 fun as_notnullable
: MType
928 private var as_nullable_cache
: nullable MType = null
931 # The depth of the type seen as a tree.
938 # Formal types have a depth of 1.
944 # The length of the type seen as a tree.
951 # Formal types have a length of 1.
957 # Compute all the classdefs inherited/imported.
958 # The returned set contains:
959 # * the class definitions from `mmodule` and its imported modules
960 # * the class definitions of this type and its super-types
962 # This function is used mainly internally.
964 # REQUIRE: `not self.need_anchor`
965 fun collect_mclassdefs
(mmodule
: MModule): Set[MClassDef] is abstract
967 # Compute all the super-classes.
968 # This function is used mainly internally.
970 # REQUIRE: `not self.need_anchor`
971 fun collect_mclasses
(mmodule
: MModule): Set[MClass] is abstract
973 # Compute all the declared super-types.
974 # Super-types are returned as declared in the classdefs (verbatim).
975 # This function is used mainly internally.
977 # REQUIRE: `not self.need_anchor`
978 fun collect_mtypes
(mmodule
: MModule): Set[MClassType] is abstract
980 # Is the property in self for a given module
981 # This method does not filter visibility or whatever
983 # REQUIRE: `not self.need_anchor`
984 fun has_mproperty
(mmodule
: MModule, mproperty
: MProperty): Bool
986 assert not self.need_anchor
987 return self.collect_mclassdefs
(mmodule
).has
(mproperty
.intro_mclassdef
)
991 # A type based on a class.
993 # `MClassType` have properties (see `has_mproperty`).
997 # The associated class
1000 redef fun model
do return self.mclass
.intro_mmodule
.model
1002 # TODO: private init because strongly bounded to its mclass. see `mclass.mclass_type`
1004 # The formal arguments of the type
1005 # ENSURE: `result.length == self.mclass.arity`
1006 var arguments
= new Array[MType]
1008 redef fun to_s
do return mclass
.to_s
1010 redef fun need_anchor
do return false
1012 redef fun anchor_to
(mmodule
: MModule, anchor
: MClassType): MClassType
1014 return super.as(MClassType)
1017 redef fun resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule, cleanup_virtual
: Bool): MClassType do return self
1019 redef fun can_resolve_for
(mtype
, anchor
, mmodule
) do return true
1021 redef fun collect_mclassdefs
(mmodule
)
1023 assert not self.need_anchor
1024 var cache
= self.collect_mclassdefs_cache
1025 if not cache
.has_key
(mmodule
) then
1026 self.collect_things
(mmodule
)
1028 return cache
[mmodule
]
1031 redef fun collect_mclasses
(mmodule
)
1033 assert not self.need_anchor
1034 var cache
= self.collect_mclasses_cache
1035 if not cache
.has_key
(mmodule
) then
1036 self.collect_things
(mmodule
)
1038 return cache
[mmodule
]
1041 redef fun collect_mtypes
(mmodule
)
1043 assert not self.need_anchor
1044 var cache
= self.collect_mtypes_cache
1045 if not cache
.has_key
(mmodule
) then
1046 self.collect_things
(mmodule
)
1048 return cache
[mmodule
]
1051 # common implementation for `collect_mclassdefs`, `collect_mclasses`, and `collect_mtypes`.
1052 private fun collect_things
(mmodule
: MModule)
1054 var res
= new HashSet[MClassDef]
1055 var seen
= new HashSet[MClass]
1056 var types
= new HashSet[MClassType]
1057 seen
.add
(self.mclass
)
1058 var todo
= [self.mclass
]
1059 while not todo
.is_empty
do
1060 var mclass
= todo
.pop
1061 #print "process {mclass}"
1062 for mclassdef
in mclass
.mclassdefs
do
1063 if not mmodule
.in_importation
<= mclassdef
.mmodule
then continue
1064 #print " process {mclassdef}"
1066 for supertype
in mclassdef
.supertypes
do
1067 types
.add
(supertype
)
1068 var superclass
= supertype
.mclass
1069 if seen
.has
(superclass
) then continue
1070 #print " add {superclass}"
1071 seen
.add
(superclass
)
1072 todo
.add
(superclass
)
1076 collect_mclassdefs_cache
[mmodule
] = res
1077 collect_mclasses_cache
[mmodule
] = seen
1078 collect_mtypes_cache
[mmodule
] = types
1081 private var collect_mclassdefs_cache
= new HashMap[MModule, Set[MClassDef]]
1082 private var collect_mclasses_cache
= new HashMap[MModule, Set[MClass]]
1083 private var collect_mtypes_cache
= new HashMap[MModule, Set[MClassType]]
1087 # A type based on a generic class.
1088 # A generic type a just a class with additional formal generic arguments.
1094 # TODO: private init because strongly bounded to its mclass. see `mclass.get_mtype`
1098 assert self.mclass
.arity
== arguments
.length
1100 self.need_anchor
= false
1101 for t
in arguments
do
1102 if t
.need_anchor
then
1103 self.need_anchor
= true
1108 self.to_s
= "{mclass}[{arguments.join(", ")}]"
1111 # Recursively print the type of the arguments within brackets.
1112 # Example: `"Map[String, List[Int]]"`
1113 redef var to_s
: String is noinit
1115 redef var need_anchor
: Bool is noinit
1117 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1119 if not need_anchor
then return self
1120 assert can_resolve_for
(mtype
, anchor
, mmodule
)
1121 var types
= new Array[MType]
1122 for t
in arguments
do
1123 types
.add
(t
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
))
1125 return mclass
.get_mtype
(types
)
1128 redef fun can_resolve_for
(mtype
, anchor
, mmodule
)
1130 if not need_anchor
then return true
1131 for t
in arguments
do
1132 if not t
.can_resolve_for
(mtype
, anchor
, mmodule
) then return false
1141 for a
in self.arguments
do
1143 if d
> dmax
then dmax
= d
1151 for a
in self.arguments
do
1158 # A virtual formal type.
1162 # The property associated with the type.
1163 # Its the definitions of this property that determine the bound or the virtual type.
1164 var mproperty
: MProperty
1166 redef fun model
do return self.mproperty
.intro_mclassdef
.mmodule
.model
1168 # Lookup the bound for a given resolved_receiver
1169 # The result may be a other virtual type (or a parameter type)
1171 # The result is returned exactly as declared in the "type" property (verbatim).
1173 # In case of conflict, the method aborts.
1174 fun lookup_bound
(mmodule
: MModule, resolved_receiver
: MType): MType
1176 assert not resolved_receiver
.need_anchor
1177 var props
= self.mproperty
.lookup_definitions
(mmodule
, resolved_receiver
)
1178 if props
.is_empty
then
1180 else if props
.length
== 1 then
1181 return props
.first
.as(MVirtualTypeDef).bound
.as(not null)
1183 var types
= new ArraySet[MType]
1185 types
.add
(p
.as(MVirtualTypeDef).bound
.as(not null))
1187 if types
.length
== 1 then
1193 # Is the virtual type fixed for a given resolved_receiver?
1194 fun is_fixed
(mmodule
: MModule, resolved_receiver
: MType): Bool
1196 assert not resolved_receiver
.need_anchor
1197 var props
= self.mproperty
.lookup_definitions
(mmodule
, resolved_receiver
)
1198 if props
.is_empty
then
1202 if p
.as(MVirtualTypeDef).is_fixed
then return true
1207 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1209 assert can_resolve_for
(mtype
, anchor
, mmodule
)
1210 # self is a virtual type declared (or inherited) in mtype
1211 # The point of the function it to get the bound of the virtual type that make sense for mtype
1212 # But because mtype is maybe a virtual/formal type, we need to get a real receiver first
1213 #print "{class_name}: {self}/{mtype}/{anchor}?"
1214 var resolved_reciever
1215 if mtype
.need_anchor
then
1216 assert anchor
!= null
1217 resolved_reciever
= mtype
.resolve_for
(anchor
, null, mmodule
, true)
1219 resolved_reciever
= mtype
1221 # Now, we can get the bound
1222 var verbatim_bound
= lookup_bound
(mmodule
, resolved_reciever
)
1223 # The bound is exactly as declared in the "type" property, so we must resolve it again
1224 var res
= verbatim_bound
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1225 #print "{class_name}: {self}/{mtype}/{anchor} -> {self}/{resolved_receiver}/{anchor} -> {verbatim_bound}/{mtype}/{anchor} -> {res}"
1227 # What to return here? There is a bunch a special cases:
1228 # If 'cleanup_virtual' we must return the resolved type, since we cannot return self
1229 if cleanup_virtual
then return res
1230 # If the receiver 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
1231 if resolved_reciever
isa MNullableType then resolved_reciever
= resolved_reciever
.mtype
1232 if resolved_reciever
.as(MClassType).mclass
.kind
== enum_kind
then return res
1233 # 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.
1234 if res
isa MVirtualType then return res
1235 # If we are final, just return the resolution
1236 if is_fixed
(mmodule
, resolved_reciever
) then return res
1237 # If the resolved type isa intern class, then there is no possible valid redefinition in any potential subclass. self is just fixed. so simply return the resolution
1238 if res
isa MClassType and res
.mclass
.kind
== enum_kind
then return res
1239 # TODO: What if bound to a MParameterType?
1240 # Note that Nullable types can always be redefined by the non nullable version, so there is no specific case on it.
1242 # If anything apply, then `self' cannot be resolved, so return self
1246 redef fun can_resolve_for
(mtype
, anchor
, mmodule
)
1248 if mtype
.need_anchor
then
1249 assert anchor
!= null
1250 mtype
= mtype
.anchor_to
(mmodule
, anchor
)
1252 return mtype
.has_mproperty
(mmodule
, mproperty
)
1255 redef fun to_s
do return self.mproperty
.to_s
1258 # The type associated to a formal parameter generic type of a class
1260 # Each parameter type is associated to a specific class.
1261 # It means that all refinements of a same class "share" the parameter type,
1262 # but that a generic subclass has its own parameter types.
1264 # However, in the sense of the meta-model, a parameter type of a class is
1265 # a valid type in a subclass. The "in the sense of the meta-model" is
1266 # important because, in the Nit language, the programmer cannot refers
1267 # directly to the parameter types of the super-classes.
1272 # fun e: E is abstract
1278 # In the class definition B[F], `F` is a valid type but `E` is not.
1279 # However, `self.e` is a valid method call, and the signature of `e` is
1282 # Note that parameter types are shared among class refinements.
1283 # Therefore parameter only have an internal name (see `to_s` for details).
1284 class MParameterType
1287 # The generic class where the parameter belong
1290 redef fun model
do return self.mclass
.intro_mmodule
.model
1292 # The position of the parameter (0 for the first parameter)
1293 # FIXME: is `position` a better name?
1298 redef fun to_s
do return name
1300 # Resolve the bound for a given resolved_receiver
1301 # The result may be a other virtual type (or a parameter type)
1302 fun lookup_bound
(mmodule
: MModule, resolved_receiver
: MType): MType
1304 assert not resolved_receiver
.need_anchor
1305 var goalclass
= self.mclass
1306 var supertypes
= resolved_receiver
.collect_mtypes
(mmodule
)
1307 for t
in supertypes
do
1308 if t
.mclass
== goalclass
then
1309 # Yeah! c specialize goalclass with a "super `t'". So the question is what is the argument of f
1310 # FIXME: Here, we stop on the first goal. Should we check others and detect inconsistencies?
1311 var res
= t
.arguments
[self.rank
]
1318 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1320 assert can_resolve_for
(mtype
, anchor
, mmodule
)
1321 #print "{class_name}: {self}/{mtype}/{anchor}?"
1323 if mtype
isa MGenericType and mtype
.mclass
== self.mclass
then
1324 var res
= mtype
.arguments
[self.rank
]
1325 if anchor
!= null and res
.need_anchor
then
1326 # Maybe the result can be resolved more if are bound to a final class
1327 var r2
= res
.anchor_to
(mmodule
, anchor
)
1328 if r2
isa MClassType and r2
.mclass
.kind
== enum_kind
then return r2
1333 # self is a parameter type of mtype (or of a super-class of mtype)
1334 # The point of the function it to get the bound of the virtual type that make sense for mtype
1335 # But because mtype is maybe a virtual/formal type, we need to get a real receiver first
1336 # FIXME: What happens here is far from clear. Thus this part must be validated and clarified
1337 var resolved_receiver
1338 if mtype
.need_anchor
then
1339 assert anchor
!= null
1340 resolved_receiver
= mtype
.resolve_for
(anchor
.mclass
.mclass_type
, anchor
, mmodule
, true)
1342 resolved_receiver
= mtype
1344 if resolved_receiver
isa MNullableType then resolved_receiver
= resolved_receiver
.mtype
1345 if resolved_receiver
isa MParameterType then
1346 assert resolved_receiver
.mclass
== anchor
.mclass
1347 resolved_receiver
= anchor
.arguments
[resolved_receiver
.rank
]
1348 if resolved_receiver
isa MNullableType then resolved_receiver
= resolved_receiver
.mtype
1350 assert resolved_receiver
isa MClassType
1352 # Eh! The parameter is in the current class.
1353 # So we return the corresponding argument, no mater what!
1354 if resolved_receiver
.mclass
== self.mclass
then
1355 var res
= resolved_receiver
.arguments
[self.rank
]
1356 #print "{class_name}: {self}/{mtype}/{anchor} -> direct {res}"
1360 if resolved_receiver
.need_anchor
then
1361 assert anchor
!= null
1362 resolved_receiver
= resolved_receiver
.resolve_for
(anchor
, null, mmodule
, false)
1364 # Now, we can get the bound
1365 var verbatim_bound
= lookup_bound
(mmodule
, resolved_receiver
)
1366 # The bound is exactly as declared in the "type" property, so we must resolve it again
1367 var res
= verbatim_bound
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1369 #print "{class_name}: {self}/{mtype}/{anchor} -> indirect {res}"
1374 redef fun can_resolve_for
(mtype
, anchor
, mmodule
)
1376 if mtype
.need_anchor
then
1377 assert anchor
!= null
1378 mtype
= mtype
.anchor_to
(mmodule
, anchor
)
1380 return mtype
.collect_mclassdefs
(mmodule
).has
(mclass
.intro
)
1384 # A type prefixed with "nullable"
1388 # The base type of the nullable type
1391 redef fun model
do return self.mtype
.model
1395 self.to_s
= "nullable {mtype}"
1398 redef var to_s
: String is noinit
1400 redef fun need_anchor
do return mtype
.need_anchor
1401 redef fun as_nullable
do return self
1402 redef fun as_notnullable
do return mtype
1403 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1405 var res
= self.mtype
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1406 return res
.as_nullable
1409 redef fun can_resolve_for
(mtype
, anchor
, mmodule
)
1411 return self.mtype
.can_resolve_for
(mtype
, anchor
, mmodule
)
1414 redef fun depth
do return self.mtype
.depth
1416 redef fun length
do return self.mtype
.length
1418 redef fun collect_mclassdefs
(mmodule
)
1420 assert not self.need_anchor
1421 return self.mtype
.collect_mclassdefs
(mmodule
)
1424 redef fun collect_mclasses
(mmodule
)
1426 assert not self.need_anchor
1427 return self.mtype
.collect_mclasses
(mmodule
)
1430 redef fun collect_mtypes
(mmodule
)
1432 assert not self.need_anchor
1433 return self.mtype
.collect_mtypes
(mmodule
)
1437 # The type of the only value null
1439 # The is only one null type per model, see `MModel::null_type`.
1442 redef var model
: Model
1443 redef fun to_s
do return "null"
1444 redef fun as_nullable
do return self
1445 redef fun need_anchor
do return false
1446 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
) do return self
1447 redef fun can_resolve_for
(mtype
, anchor
, mmodule
) do return true
1449 redef fun collect_mclassdefs
(mmodule
) do return new HashSet[MClassDef]
1451 redef fun collect_mclasses
(mmodule
) do return new HashSet[MClass]
1453 redef fun collect_mtypes
(mmodule
) do return new HashSet[MClassType]
1456 # A signature of a method
1460 # The each parameter (in order)
1461 var mparameters
: Array[MParameter]
1463 # The return type (null for a procedure)
1464 var return_mtype
: nullable MType
1469 var t
= self.return_mtype
1470 if t
!= null then dmax
= t
.depth
1471 for p
in mparameters
do
1472 var d
= p
.mtype
.depth
1473 if d
> dmax
then dmax
= d
1481 var t
= self.return_mtype
1482 if t
!= null then res
+= t
.length
1483 for p
in mparameters
do
1484 res
+= p
.mtype
.length
1489 # REQUIRE: 1 <= mparameters.count p -> p.is_vararg
1492 var vararg_rank
= -1
1493 for i
in [0..mparameters
.length
[ do
1494 var parameter
= mparameters
[i
]
1495 if parameter
.is_vararg
then
1496 assert vararg_rank
== -1
1500 self.vararg_rank
= vararg_rank
1503 # The rank of the ellipsis (`...`) for vararg (starting from 0).
1504 # value is -1 if there is no vararg.
1505 # Example: for "(a: Int, b: Bool..., c: Char)" #-> vararg_rank=1
1506 var vararg_rank
: Int is noinit
1508 # The number or parameters
1509 fun arity
: Int do return mparameters
.length
1513 var b
= new FlatBuffer
1514 if not mparameters
.is_empty
then
1516 for i
in [0..mparameters
.length
[ do
1517 var mparameter
= mparameters
[i
]
1518 if i
> 0 then b
.append
(", ")
1519 b
.append
(mparameter
.name
)
1521 b
.append
(mparameter
.mtype
.to_s
)
1522 if mparameter
.is_vararg
then
1528 var ret
= self.return_mtype
1536 redef fun resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule, cleanup_virtual
: Bool): MSignature
1538 var params
= new Array[MParameter]
1539 for p
in self.mparameters
do
1540 params
.add
(p
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
))
1542 var ret
= self.return_mtype
1544 ret
= ret
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1546 var res
= new MSignature(params
, ret
)
1551 # A parameter in a signature
1555 # The name of the parameter
1556 redef var name
: String
1558 # The static type of the parameter
1561 # Is the parameter a vararg?
1567 return "{name}: {mtype}..."
1569 return "{name}: {mtype}"
1573 fun resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule, cleanup_virtual
: Bool): MParameter
1575 if not self.mtype
.need_anchor
then return self
1576 var newtype
= self.mtype
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1577 var res
= new MParameter(self.name
, newtype
, self.is_vararg
)
1581 redef fun model
do return mtype
.model
1584 # A service (global property) that generalize method, attribute, etc.
1586 # `MProperty` are global to the model; it means that a `MProperty` is not bound
1587 # to a specific `MModule` nor a specific `MClass`.
1589 # A MProperty gather definitions (see `mpropdefs`) ; one for the introduction
1590 # and the other in subclasses and in refinements.
1592 # A `MProperty` is used to denotes services in polymorphic way (ie. independent
1593 # of any dynamic type).
1594 # For instance, a call site "x.foo" is associated to a `MProperty`.
1595 abstract class MProperty
1598 # The associated MPropDef subclass.
1599 # The two specialization hierarchy are symmetric.
1600 type MPROPDEF: MPropDef
1602 # The classdef that introduce the property
1603 # While a property is not bound to a specific module, or class,
1604 # the introducing mclassdef is used for naming and visibility
1605 var intro_mclassdef
: MClassDef
1607 # The (short) name of the property
1608 redef var name
: String
1610 # The canonical name of the property
1611 # Example: "owner::my_module::MyClass::my_method"
1612 fun full_name
: String
1614 return "{self.intro_mclassdef.mmodule.full_name}::{self.intro_mclassdef.mclass.name}::{name}"
1617 # The visibility of the property
1618 var visibility
: MVisibility
1622 intro_mclassdef
.intro_mproperties
.add
(self)
1623 var model
= intro_mclassdef
.mmodule
.model
1624 model
.mproperties_by_name
.add_one
(name
, self)
1625 model
.mproperties
.add
(self)
1628 # All definitions of the property.
1629 # The first is the introduction,
1630 # The other are redefinitions (in refinements and in subclasses)
1631 var mpropdefs
= new Array[MPROPDEF]
1633 # The definition that introduces the property.
1635 # Warning: such a definition may not exist in the early life of the object.
1636 # In this case, the method will abort.
1637 var intro
: MPROPDEF is noinit
1639 redef fun model
do return intro
.model
1642 redef fun to_s
do return name
1644 # Return the most specific property definitions defined or inherited by a type.
1645 # The selection knows that refinement is stronger than specialization;
1646 # however, in case of conflict more than one property are returned.
1647 # If mtype does not know mproperty then an empty array is returned.
1649 # If you want the really most specific property, then look at `lookup_first_definition`
1650 fun lookup_definitions
(mmodule
: MModule, mtype
: MType): Array[MPROPDEF]
1652 assert not mtype
.need_anchor
1653 mtype
= mtype
.as_notnullable
1655 var cache
= self.lookup_definitions_cache
[mmodule
, mtype
]
1656 if cache
!= null then return cache
1658 #print "select prop {mproperty} for {mtype} in {self}"
1659 # First, select all candidates
1660 var candidates
= new Array[MPROPDEF]
1661 for mpropdef
in self.mpropdefs
do
1662 # If the definition is not imported by the module, then skip
1663 if not mmodule
.in_importation
<= mpropdef
.mclassdef
.mmodule
then continue
1664 # If the definition is not inherited by the type, then skip
1665 if not mtype
.is_subtype
(mmodule
, null, mpropdef
.mclassdef
.bound_mtype
) then continue
1667 candidates
.add
(mpropdef
)
1669 # Fast track for only one candidate
1670 if candidates
.length
<= 1 then
1671 self.lookup_definitions_cache
[mmodule
, mtype
] = candidates
1675 # Second, filter the most specific ones
1676 return select_most_specific
(mmodule
, candidates
)
1679 private var lookup_definitions_cache
= new HashMap2[MModule, MType, Array[MPROPDEF]]
1681 # Return the most specific property definitions inherited by a type.
1682 # The selection knows that refinement is stronger than specialization;
1683 # however, in case of conflict more than one property are returned.
1684 # If mtype does not know mproperty then an empty array is returned.
1686 # If you want the really most specific property, then look at `lookup_next_definition`
1688 # FIXME: Move to `MPropDef`?
1689 fun lookup_super_definitions
(mmodule
: MModule, mtype
: MType): Array[MPROPDEF]
1691 assert not mtype
.need_anchor
1692 mtype
= mtype
.as_notnullable
1694 # First, select all candidates
1695 var candidates
= new Array[MPROPDEF]
1696 for mpropdef
in self.mpropdefs
do
1697 # If the definition is not imported by the module, then skip
1698 if not mmodule
.in_importation
<= mpropdef
.mclassdef
.mmodule
then continue
1699 # If the definition is not inherited by the type, then skip
1700 if not mtype
.is_subtype
(mmodule
, null, mpropdef
.mclassdef
.bound_mtype
) then continue
1701 # If the definition is defined by the type, then skip (we want the super, so e skip the current)
1702 if mtype
== mpropdef
.mclassdef
.bound_mtype
and mmodule
== mpropdef
.mclassdef
.mmodule
then continue
1704 candidates
.add
(mpropdef
)
1706 # Fast track for only one candidate
1707 if candidates
.length
<= 1 then return candidates
1709 # Second, filter the most specific ones
1710 return select_most_specific
(mmodule
, candidates
)
1713 # Return an array containing olny the most specific property definitions
1714 # This is an helper function for `lookup_definitions` and `lookup_super_definitions`
1715 private fun select_most_specific
(mmodule
: MModule, candidates
: Array[MPROPDEF]): Array[MPROPDEF]
1717 var res
= new Array[MPROPDEF]
1718 for pd1
in candidates
do
1719 var cd1
= pd1
.mclassdef
1722 for pd2
in candidates
do
1723 if pd2
== pd1
then continue # do not compare with self!
1724 var cd2
= pd2
.mclassdef
1726 if c2
.mclass_type
== c1
.mclass_type
then
1727 if cd2
.mmodule
.in_importation
< cd1
.mmodule
then
1728 # cd2 refines cd1; therefore we skip pd1
1732 else if cd2
.bound_mtype
.is_subtype
(mmodule
, null, cd1
.bound_mtype
) and cd2
.bound_mtype
!= cd1
.bound_mtype
then
1733 # cd2 < cd1; therefore we skip pd1
1742 if res
.is_empty
then
1743 print
"All lost! {candidates.join(", ")}"
1744 # FIXME: should be abort!
1749 # Return the most specific definition in the linearization of `mtype`.
1751 # If you want to know the next properties in the linearization,
1752 # look at `MPropDef::lookup_next_definition`.
1754 # FIXME: the linearization is still unspecified
1756 # REQUIRE: `not mtype.need_anchor`
1757 # REQUIRE: `mtype.has_mproperty(mmodule, self)`
1758 fun lookup_first_definition
(mmodule
: MModule, mtype
: MType): MPROPDEF
1760 assert mtype
.has_mproperty
(mmodule
, self)
1761 return lookup_all_definitions
(mmodule
, mtype
).first
1764 # Return all definitions in a linearization order
1765 # Most specific first, most general last
1766 fun lookup_all_definitions
(mmodule
: MModule, mtype
: MType): Array[MPROPDEF]
1768 assert not mtype
.need_anchor
1769 mtype
= mtype
.as_notnullable
1771 var cache
= self.lookup_all_definitions_cache
[mmodule
, mtype
]
1772 if cache
!= null then return cache
1774 #print "select prop {mproperty} for {mtype} in {self}"
1775 # First, select all candidates
1776 var candidates
= new Array[MPROPDEF]
1777 for mpropdef
in self.mpropdefs
do
1778 # If the definition is not imported by the module, then skip
1779 if not mmodule
.in_importation
<= mpropdef
.mclassdef
.mmodule
then continue
1780 # If the definition is not inherited by the type, then skip
1781 if not mtype
.is_subtype
(mmodule
, null, mpropdef
.mclassdef
.bound_mtype
) then continue
1783 candidates
.add
(mpropdef
)
1785 # Fast track for only one candidate
1786 if candidates
.length
<= 1 then
1787 self.lookup_all_definitions_cache
[mmodule
, mtype
] = candidates
1791 mmodule
.linearize_mpropdefs
(candidates
)
1792 candidates
= candidates
.reversed
1793 self.lookup_all_definitions_cache
[mmodule
, mtype
] = candidates
1797 private var lookup_all_definitions_cache
= new HashMap2[MModule, MType, Array[MPROPDEF]]
1804 redef type MPROPDEF: MMethodDef
1806 # Is the property defined at the top_level of the module?
1807 # Currently such a property are stored in `Object`
1808 var is_toplevel
: Bool = false is writable
1810 # Is the property a constructor?
1811 # Warning, this property can be inherited by subclasses with or without being a constructor
1812 # therefore, you should use `is_init_for` the verify if the property is a legal constructor for a given class
1813 var is_init
: Bool = false is writable
1815 # The constructor is a (the) root init with empty signature but a set of initializers
1816 var is_root_init
: Bool = false is writable
1818 # Is the property a 'new' constructor?
1819 var is_new
: Bool = false is writable
1821 # Is the property a legal constructor for a given class?
1822 # As usual, visibility is not considered.
1823 # FIXME not implemented
1824 fun is_init_for
(mclass
: MClass): Bool
1830 # A global attribute
1834 redef type MPROPDEF: MAttributeDef
1838 # A global virtual type
1839 class MVirtualTypeProp
1842 redef type MPROPDEF: MVirtualTypeDef
1844 # The formal type associated to the virtual type property
1845 var mvirtualtype
= new MVirtualType(self)
1848 # A definition of a property (local property)
1850 # Unlike `MProperty`, a `MPropDef` is a local definition that belong to a
1851 # specific class definition (which belong to a specific module)
1852 abstract class MPropDef
1855 # The associated `MProperty` subclass.
1856 # the two specialization hierarchy are symmetric
1857 type MPROPERTY: MProperty
1860 type MPROPDEF: MPropDef
1862 # The class definition where the property definition is
1863 var mclassdef
: MClassDef
1865 # The associated global property
1866 var mproperty
: MPROPERTY
1868 # The origin of the definition
1869 var location
: Location
1873 mclassdef
.mpropdefs
.add
(self)
1874 mproperty
.mpropdefs
.add
(self)
1875 if mproperty
.intro_mclassdef
== mclassdef
then
1876 assert not isset mproperty
._intro
1877 mproperty
.intro
= self
1879 self.to_s
= "{mclassdef}#{mproperty}"
1882 # Actually the name of the `mproperty`
1883 redef fun name
do return mproperty
.name
1885 redef fun model
do return mclassdef
.model
1887 # Internal name combining the module, the class and the property
1888 # Example: "mymodule#MyClass#mymethod"
1889 redef var to_s
: String is noinit
1891 # Is self the definition that introduce the property?
1892 fun is_intro
: Bool do return mproperty
.intro
== self
1894 # Return the next definition in linearization of `mtype`.
1896 # This method is used to determine what method is called by a super.
1898 # REQUIRE: `not mtype.need_anchor`
1899 fun lookup_next_definition
(mmodule
: MModule, mtype
: MType): MPROPDEF
1901 assert not mtype
.need_anchor
1903 var mpropdefs
= self.mproperty
.lookup_all_definitions
(mmodule
, mtype
)
1904 var i
= mpropdefs
.iterator
1905 while i
.is_ok
and i
.item
!= self do i
.next
1906 assert has_property
: i
.is_ok
1908 assert has_next_property
: i
.is_ok
1913 # A local definition of a method
1917 redef type MPROPERTY: MMethod
1918 redef type MPROPDEF: MMethodDef
1920 # The signature attached to the property definition
1921 var msignature
: nullable MSignature = null is writable
1923 # The signature attached to the `new` call on a root-init
1924 # This is a concatenation of the signatures of the initializers
1926 # REQUIRE `mproperty.is_root_init == (new_msignature != null)`
1927 var new_msignature
: nullable MSignature = null is writable
1929 # List of initialisers to call in root-inits
1931 # They could be setters or attributes
1933 # REQUIRE `mproperty.is_root_init == (new_msignature != null)`
1934 var initializers
= new Array[MProperty]
1936 # Is the method definition abstract?
1937 var is_abstract
: Bool = false is writable
1939 # Is the method definition intern?
1940 var is_intern
= false is writable
1942 # Is the method definition extern?
1943 var is_extern
= false is writable
1945 # An optional constant value returned in functions.
1947 # Only some specific primitife value are accepted by engines.
1948 # Is used when there is no better implementation available.
1950 # Currently used only for the implementation of the `--define`
1951 # command-line option.
1952 # SEE: module `mixin`.
1953 var constant_value
: nullable Object = null is writable
1956 # A local definition of an attribute
1960 redef type MPROPERTY: MAttribute
1961 redef type MPROPDEF: MAttributeDef
1963 # The static type of the attribute
1964 var static_mtype
: nullable MType = null is writable
1967 # A local definition of a virtual type
1968 class MVirtualTypeDef
1971 redef type MPROPERTY: MVirtualTypeProp
1972 redef type MPROPDEF: MVirtualTypeDef
1974 # The bound of the virtual type
1975 var bound
: nullable MType = null is writable
1977 # Is the bound fixed?
1978 var is_fixed
= false is writable
1985 # * `interface_kind`
1989 # Note this class is basically an enum.
1990 # FIXME: use a real enum once user-defined enums are available
1992 redef var to_s
: String
1994 # Is a constructor required?
1997 # TODO: private init because enumeration.
1999 # Can a class of kind `self` specializes a class of kine `other`?
2000 fun can_specialize
(other
: MClassKind): Bool
2002 if other
== interface_kind
then return true # everybody can specialize interfaces
2003 if self == interface_kind
or self == enum_kind
then
2004 # no other case for interfaces
2006 else if self == extern_kind
then
2007 # only compatible with themselves
2008 return self == other
2009 else if other
== enum_kind
or other
== extern_kind
then
2010 # abstract_kind and concrete_kind are incompatible
2013 # remain only abstract_kind and concrete_kind
2018 # The class kind `abstract`
2019 fun abstract_kind
: MClassKind do return once
new MClassKind("abstract class", true)
2020 # The class kind `concrete`
2021 fun concrete_kind
: MClassKind do return once
new MClassKind("class", true)
2022 # The class kind `interface`
2023 fun interface_kind
: MClassKind do return once
new MClassKind("interface", false)
2024 # The class kind `enum`
2025 fun enum_kind
: MClassKind do return once
new MClassKind("enum", false)
2026 # The class kind `extern`
2027 fun extern_kind
: MClassKind do return once
new MClassKind("extern class", false)