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 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 fun finalizable_type
: nullable MClassType
242 var clas
= self.model
.get_mclasses_by_name
("Finalizable")
243 if clas
== null then return null
244 return get_primitive_class
("Finalizable").mclass_type
247 # Force to get the primitive class named `name` or abort
248 fun get_primitive_class
(name
: String): MClass
250 var cla
= self.model
.get_mclasses_by_name
(name
)
252 if name
== "Bool" then
253 var c
= new MClass(self, name
, null, enum_kind
, public_visibility
)
254 var cladef
= new MClassDef(self, c
.mclass_type
, new Location(null, 0,0,0,0))
257 print
("Fatal Error: no primitive class {name}")
260 if cla
.length
!= 1 then
261 var msg
= "Fatal Error: more than one primitive class {name}:"
262 for c
in cla
do msg
+= " {c.full_name}"
269 # Try to get the primitive method named `name` on the type `recv`
270 fun try_get_primitive_method
(name
: String, recv
: MClass): nullable MMethod
272 var props
= self.model
.get_mproperties_by_name
(name
)
273 if props
== null then return null
274 var res
: nullable MMethod = null
275 for mprop
in props
do
276 assert mprop
isa MMethod
277 var intro
= mprop
.intro_mclassdef
278 for mclassdef
in recv
.mclassdefs
do
279 if not self.in_importation
.greaters
.has
(mclassdef
.mmodule
) then continue
280 if not mclassdef
.in_hierarchy
.greaters
.has
(intro
) then continue
283 else if res
!= mprop
then
284 print
("Fatal Error: ambigous property name '{name}'; conflict between {mprop.full_name} and {res.full_name}")
293 private class MClassDefSorter
294 super AbstractSorter[MClassDef]
296 redef fun compare
(a
, b
)
300 if ca
!= cb
then return mmodule
.flatten_mclass_hierarchy
.compare
(ca
, cb
)
301 return mmodule
.model
.mclassdef_hierarchy
.compare
(a
, b
)
305 private class MPropDefSorter
306 super AbstractSorter[MPropDef]
308 redef fun compare
(pa
, pb
)
314 if ca
!= cb
then return mmodule
.flatten_mclass_hierarchy
.compare
(ca
, cb
)
315 return mmodule
.model
.mclassdef_hierarchy
.compare
(a
, b
)
321 # `MClass` are global to the model; it means that a `MClass` is not bound to a
322 # specific `MModule`.
324 # This characteristic helps the reasoning about classes in a program since a
325 # single `MClass` object always denote the same class.
327 # The drawback is that classes (`MClass`) contain almost nothing by themselves.
328 # These do not really have properties nor belong to a hierarchy since the property and the
329 # hierarchy of a class depends of the refinement in the modules.
331 # Most services on classes require the precision of a module, and no one can asks what are
332 # the super-classes of a class nor what are properties of a class without precising what is
333 # the module considered.
335 # For instance, during the typing of a source-file, the module considered is the module of the file.
336 # eg. the question *is the method `foo` exists in the class `Bar`?* must be reformulated into
337 # *is the method `foo` exists in the class `Bar` in the current module?*
339 # During some global analysis, the module considered may be the main module of the program.
343 # The module that introduce the class
344 # While classes are not bound to a specific module,
345 # the introducing module is used for naming an visibility
346 var intro_mmodule
: MModule
348 # The short name of the class
349 # In Nit, the name of a class cannot evolve in refinements
350 redef var name
: String
352 # The canonical name of the class
353 # Example: `"owner::module::MyClass"`
354 fun full_name
: String
356 return "{self.intro_mmodule.full_name}::{name}"
359 # The number of generic formal parameters
360 # 0 if the class is not generic
363 # Each generic formal parameters in order.
364 # is empty if the class is not generic
365 var mparameters
= new Array[MParameterType]
367 # The kind of the class (interface, abstract class, etc.)
368 # In Nit, the kind of a class cannot evolve in refinements
371 # The visibility of the class
372 # In Nit, the visibility of a class cannot evolve in refinements
373 var visibility
: MVisibility
375 init(intro_mmodule
: MModule, name
: String, parameter_names
: nullable Array[String], kind
: MClassKind, visibility
: MVisibility)
377 self.intro_mmodule
= intro_mmodule
379 if parameter_names
== null then
382 self.arity
= parameter_names
.length
385 self.visibility
= visibility
386 intro_mmodule
.intro_mclasses
.add
(self)
387 var model
= intro_mmodule
.model
388 model
.mclasses_by_name
.add_one
(name
, self)
389 model
.mclasses
.add
(self)
391 # Create the formal parameter types
393 assert parameter_names
!= null
394 var mparametertypes
= new Array[MParameterType]
395 for i
in [0..arity
[ do
396 var mparametertype
= new MParameterType(self, i
, parameter_names
[i
])
397 mparametertypes
.add
(mparametertype
)
399 self.mparameters
= mparametertypes
400 var mclass_type
= new MGenericType(self, mparametertypes
)
401 self.mclass_type
= mclass_type
402 self.get_mtype_cache
.add
(mclass_type
)
404 self.mclass_type
= new MClassType(self)
408 redef fun model
do return intro_mmodule
.model
410 # All class definitions (introduction and refinements)
411 var mclassdefs
: Array[MClassDef] = new Array[MClassDef]
414 redef fun to_s
do return self.name
416 # The definition that introduced the class
417 # Warning: the introduction is the first `MClassDef` object associated
418 # to self. If self is just created without having any associated
419 # definition, this method will abort
422 assert has_a_first_definition
: not mclassdefs
.is_empty
423 return mclassdefs
.first
426 # Return the class `self` in the class hierarchy of the module `mmodule`.
428 # SEE: `MModule::flatten_mclass_hierarchy`
429 # REQUIRE: `mmodule.has_mclass(self)`
430 fun in_hierarchy
(mmodule
: MModule): POSetElement[MClass]
432 return mmodule
.flatten_mclass_hierarchy
[self]
435 # The principal static type of the class.
437 # For non-generic class, mclass_type is the only `MClassType` based
440 # For a generic class, the arguments are the formal parameters.
441 # i.e.: for the class Array[E:Object], the `mclass_type` is Array[E].
442 # If you want Array[Object] the see `MClassDef::bound_mtype`
444 # For generic classes, the mclass_type is also the way to get a formal
445 # generic parameter type.
447 # To get other types based on a generic class, see `get_mtype`.
449 # ENSURE: `mclass_type.mclass == self`
450 var mclass_type
: MClassType
452 # Return a generic type based on the class
453 # Is the class is not generic, then the result is `mclass_type`
455 # REQUIRE: `mtype_arguments.length == self.arity`
456 fun get_mtype
(mtype_arguments
: Array[MType]): MClassType
458 assert mtype_arguments
.length
== self.arity
459 if self.arity
== 0 then return self.mclass_type
460 for t
in self.get_mtype_cache
do
461 if t
.arguments
== mtype_arguments
then
465 var res
= new MGenericType(self, mtype_arguments
)
466 self.get_mtype_cache
.add res
470 private var get_mtype_cache
: Array[MGenericType] = new Array[MGenericType]
474 # A definition (an introduction or a refinement) of a class in a module
476 # A `MClassDef` is associated with an explicit (or almost) definition of a
477 # class. Unlike `MClass`, a `MClassDef` is a local definition that belong to
478 # a specific class and a specific module, and contains declarations like super-classes
481 # It is the class definitions that are the backbone of most things in the model:
482 # ClassDefs are defined with regard with other classdefs.
483 # Refinement and specialization are combined to produce a big poset called the `Model::mclassdef_hierarchy`.
485 # Moreover, the extension and the intention of types is defined by looking at the MClassDefs.
489 # The module where the definition is
492 # The associated `MClass`
495 # The bounded type associated to the mclassdef
497 # For a non-generic class, `bound_mtype` and `mclass.mclass_type`
501 # For the classdef Array[E: Object], the bound_mtype is Array[Object].
502 # If you want Array[E], then see `mclass.mclass_type`
504 # ENSURE: `bound_mtype.mclass == self.mclass`
505 var bound_mtype
: MClassType
507 # The origin of the definition
508 var location
: Location
510 # Internal name combining the module and the class
511 # Example: "mymodule#MyClass"
512 redef var to_s
: String
514 init(mmodule
: MModule, bound_mtype
: MClassType, location
: Location)
516 self.bound_mtype
= bound_mtype
517 self.mmodule
= mmodule
518 self.mclass
= bound_mtype
.mclass
519 self.location
= location
520 mmodule
.mclassdefs
.add
(self)
521 mclass
.mclassdefs
.add
(self)
522 self.to_s
= "{mmodule}#{mclass}"
525 # Actually the name of the `mclass`
526 redef fun name
do return mclass
.name
528 redef fun model
do return mmodule
.model
530 # All declared super-types
531 # FIXME: quite ugly but not better idea yet
532 var supertypes
: Array[MClassType] = new Array[MClassType]
534 # Register some super-types for the class (ie "super SomeType")
536 # The hierarchy must not already be set
537 # REQUIRE: `self.in_hierarchy == null`
538 fun set_supertypes
(supertypes
: Array[MClassType])
540 assert unique_invocation
: self.in_hierarchy
== null
541 var mmodule
= self.mmodule
542 var model
= mmodule
.model
543 var mtype
= self.bound_mtype
545 for supertype
in supertypes
do
546 self.supertypes
.add
(supertype
)
548 # Register in full_type_specialization_hierarchy
549 model
.full_mtype_specialization_hierarchy
.add_edge
(mtype
, supertype
)
550 # Register in intro_type_specialization_hierarchy
551 if mclass
.intro_mmodule
== mmodule
and supertype
.mclass
.intro_mmodule
== mmodule
then
552 model
.intro_mtype_specialization_hierarchy
.add_edge
(mtype
, supertype
)
558 # Collect the super-types (set by set_supertypes) to build the hierarchy
560 # This function can only invoked once by class
561 # REQUIRE: `self.in_hierarchy == null`
562 # ENSURE: `self.in_hierarchy != null`
565 assert unique_invocation
: self.in_hierarchy
== null
566 var model
= mmodule
.model
567 var res
= model
.mclassdef_hierarchy
.add_node
(self)
568 self.in_hierarchy
= res
569 var mtype
= self.bound_mtype
571 # Here we need to connect the mclassdef to its pairs in the mclassdef_hierarchy
572 # The simpliest way is to attach it to collect_mclassdefs
573 for mclassdef
in mtype
.collect_mclassdefs
(mmodule
) do
574 res
.poset
.add_edge
(self, mclassdef
)
578 # The view of the class definition in `mclassdef_hierarchy`
579 var in_hierarchy
: nullable POSetElement[MClassDef] = null
581 # Is the definition the one that introduced `mclass`?
582 fun is_intro
: Bool do return mclass
.intro
== self
584 # All properties introduced by the classdef
585 var intro_mproperties
: Array[MProperty] = new Array[MProperty]
587 # All property definitions in the class (introductions and redefinitions)
588 var mpropdefs
: Array[MPropDef] = new Array[MPropDef]
591 # A global static type
593 # MType are global to the model; it means that a `MType` is not bound to a
594 # specific `MModule`.
595 # This characteristic helps the reasoning about static types in a program
596 # since a single `MType` object always denote the same type.
598 # However, because a `MType` is global, it does not really have properties
599 # nor have subtypes to a hierarchy since the property and the class hierarchy
600 # depends of a module.
601 # Moreover, virtual types an formal generic parameter types also depends on
602 # a receiver to have sense.
604 # Therefore, most method of the types require a module and an anchor.
605 # The module is used to know what are the classes and the specialization
607 # The anchor is used to know what is the bound of the virtual types and formal
608 # generic parameter types.
610 # MType are not directly usable to get properties. See the `anchor_to` method
611 # and the `MClassType` class.
613 # FIXME: the order of the parameters is not the best. We mus pick on from:
614 # * foo(mmodule, anchor, othertype)
615 # * foo(othertype, anchor, mmodule)
616 # * foo(anchor, mmodule, othertype)
617 # * foo(othertype, mmodule, anchor)
621 redef fun name
do return to_s
623 # Return true if `self` is an subtype of `sup`.
624 # The typing is done using the standard typing policy of Nit.
626 # REQUIRE: `anchor == null implies not self.need_anchor and not sup.need_anchor`
627 # REQUIRE: `anchor != null implies self.can_resolve_for(anchor, null, mmodule) and sup.can_resolve_for(anchor, null, mmodule)`
628 fun is_subtype
(mmodule
: MModule, anchor
: nullable MClassType, sup
: MType): Bool
631 if sub
== sup
then return true
632 if anchor
== null then
633 assert not sub
.need_anchor
634 assert not sup
.need_anchor
636 assert sub
.can_resolve_for
(anchor
, null, mmodule
)
637 assert sup
.can_resolve_for
(anchor
, null, mmodule
)
640 # First, resolve the formal types to a common version in the receiver
641 # The trick here is that fixed formal type will be associed to the bound
642 # And unfixed formal types will be associed to a canonical formal type.
643 if sub
isa MParameterType or sub
isa MVirtualType then
644 assert anchor
!= null
645 sub
= sub
.resolve_for
(anchor
.mclass
.mclass_type
, anchor
, mmodule
, false)
647 if sup
isa MParameterType or sup
isa MVirtualType then
648 assert anchor
!= null
649 sup
= sup
.resolve_for
(anchor
.mclass
.mclass_type
, anchor
, mmodule
, false)
652 # Does `sup` accept null or not?
653 # Discard the nullable marker if it exists
654 var sup_accept_null
= false
655 if sup
isa MNullableType then
656 sup_accept_null
= true
658 else if sup
isa MNullType then
659 sup_accept_null
= true
662 # Can `sub` provide null or not?
663 # Thus we can match with `sup_accept_null`
664 # Also discard the nullable marker if it exists
665 if sub
isa MNullableType then
666 if not sup_accept_null
then return false
668 else if sub
isa MNullType then
669 return sup_accept_null
671 # Now the case of direct null and nullable is over.
673 # A unfixed formal type can only accept itself
674 if sup
isa MParameterType or sup
isa MVirtualType then
678 # If `sub` is a formal type, then it is accepted if its bound is accepted
679 if sub
isa MParameterType or sub
isa MVirtualType then
680 assert anchor
!= null
681 sub
= sub
.anchor_to
(mmodule
, anchor
)
683 # Manage the second layer of null/nullable
684 if sub
isa MNullableType then
685 if not sup_accept_null
then return false
687 else if sub
isa MNullType then
688 return sup_accept_null
692 assert sub
isa MClassType # It is the only remaining type
694 if sup
isa MNullType then
695 # `sup` accepts only null
699 assert sup
isa MClassType # It is the only remaining type
701 # Now both are MClassType, we need to dig
703 if sub
== sup
then return true
705 if anchor
== null then anchor
= sub
# UGLY: any anchor will work
706 var resolved_sub
= sub
.anchor_to
(mmodule
, anchor
)
707 var res
= resolved_sub
.collect_mclasses
(mmodule
).has
(sup
.mclass
)
708 if res
== false then return false
709 if not sup
isa MGenericType then return true
710 var sub2
= sub
.supertype_to
(mmodule
, anchor
, sup
.mclass
)
711 assert sub2
.mclass
== sup
.mclass
712 for i
in [0..sup
.mclass
.arity
[ do
713 var sub_arg
= sub2
.arguments
[i
]
714 var sup_arg
= sup
.arguments
[i
]
715 res
= sub_arg
.is_subtype
(mmodule
, anchor
, sup_arg
)
716 if res
== false then return false
721 # The base class type on which self is based
723 # This base type is used to get property (an internally to perform
724 # unsafe type comparison).
726 # Beware: some types (like null) are not based on a class thus this
729 # Basically, this function transform the virtual types and parameter
730 # types to their bounds.
734 # class B super A end
736 # class Y super X end
744 # Map[T,U] anchor_to H #-> Map[B,Y]
746 # Explanation of the example:
747 # In H, T is set to B, because "H super G[B]", and U is bound to Y,
748 # because "redef type U: Y". Therefore, Map[T, U] is bound to
751 # ENSURE: `not self.need_anchor implies result == self`
752 # ENSURE: `not result.need_anchor`
753 fun anchor_to
(mmodule
: MModule, anchor
: MClassType): MType
755 if not need_anchor
then return self
756 assert not anchor
.need_anchor
757 # Just resolve to the anchor and clear all the virtual types
758 var res
= self.resolve_for
(anchor
, null, mmodule
, true)
759 assert not res
.need_anchor
763 # Does `self` contain a virtual type or a formal generic parameter type?
764 # In order to remove those types, you usually want to use `anchor_to`.
765 fun need_anchor
: Bool do return true
767 # Return the supertype when adapted to a class.
769 # In Nit, for each super-class of a type, there is a equivalent super-type.
773 # class H[V] super G[V, Bool] end
774 # H[Int] supertype_to G #-> G[Int, Bool]
776 # REQUIRE: `super_mclass` is a super-class of `self`
777 # REQUIRE: `self.need_anchor implies anchor != null and self.can_resolve_for(anchor, null, mmodule)`
778 # ENSURE: `result.mclass = super_mclass`
779 fun supertype_to
(mmodule
: MModule, anchor
: nullable MClassType, super_mclass
: MClass): MClassType
781 if super_mclass
.arity
== 0 then return super_mclass
.mclass_type
782 if self isa MClassType and self.mclass
== super_mclass
then return self
784 if self.need_anchor
then
785 assert anchor
!= null
786 resolved_self
= self.anchor_to
(mmodule
, anchor
)
790 var supertypes
= resolved_self
.collect_mtypes
(mmodule
)
791 for supertype
in supertypes
do
792 if supertype
.mclass
== super_mclass
then
793 # FIXME: Here, we stop on the first goal. Should we check others and detect inconsistencies?
794 return supertype
.resolve_for
(self, anchor
, mmodule
, false)
800 # Replace formals generic types in self with resolved values in `mtype`
801 # If `cleanup_virtual` is true, then virtual types are also replaced
804 # This function returns self if `need_anchor` is false.
809 # class H[F] super G[F] end
812 # * Array[E].resolve_for(H[Int]) #-> Array[Int]
813 # * Array[E].resolve_for(G[Z], X[Int]) #-> Array[Z]
815 # Explanation of the example:
816 # * Array[E].need_anchor is true because there is a formal generic parameter type E
817 # * E makes sense for H[Int] because E is a formal parameter of G and H specialize G
818 # * Since "H[F] super G[F]", E is in fact F for H
819 # * More specifically, in H[Int], E is Int
820 # * So, in H[Int], Array[E] is Array[Int]
822 # This function is mainly used to inherit a signature.
823 # Because, unlike `anchor_to`, we do not want a full resolution of
824 # a type but only an adapted version of it.
829 # fun foo(e:E):E is abstract
831 # class B super A[Int] end
833 # The signature on foo is (e: E): E
834 # If we resolve the signature for B, we get (e:Int):Int
839 # fun foo(e:E) is abstract
843 # fun bar do a.foo(x) # <- x is here
846 # The first question is: is foo available on `a`?
848 # The static type of a is `A[Array[F]]`, that is an open type.
849 # in order to find a method `foo`, whe must look at a resolved type.
851 # A[Array[F]].anchor_to(B[nullable Object]) #-> A[Array[nullable Object]]
853 # the method `foo` exists in `A[Array[nullable Object]]`, therefore `foo` exists for `a`.
855 # The next question is: what is the accepted types for `x`?
857 # the signature of `foo` is `foo(e:E)`, thus we must resolve the type E
859 # E.resolve_for(A[Array[F]],B[nullable Object]) #-> Array[F]
861 # The resolution can be done because `E` make sense for the class A (see `can_resolve_for`)
863 # FIXME: the parameter `cleanup_virtual` is just a bad idea, but having
864 # two function instead of one seems also to be a bad idea.
866 # REQUIRE: `can_resolve_for(mtype, anchor, mmodule)`
867 # ENSURE: `not self.need_anchor implies result == self`
868 fun resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule, cleanup_virtual
: Bool): MType is abstract
870 # Can the type be resolved?
872 # In order to resolve open types, the formal types must make sence.
881 # * E.can_resolve_for(A[Int]) #-> true, E make sense in A
882 # * E.can_resolve_for(B[Int]) #-> false, E does not make sense in B
883 # * B[E].can_resolve_for(A[F], B[Object]) #-> true,
884 # B[E] is a red hearing only the E is important,
887 # REQUIRE: `anchor != null implies not anchor.need_anchor`
888 # REQUIRE: `mtype.need_anchor implies anchor != null and mtype.can_resolve_for(anchor, null, mmodule)`
889 # ENSURE: `not self.need_anchor implies result == true`
890 fun can_resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule): Bool is abstract
892 # Return the nullable version of the type
893 # If the type is already nullable then self is returned
894 fun as_nullable
: MType
896 var res
= self.as_nullable_cache
897 if res
!= null then return res
898 res
= new MNullableType(self)
899 self.as_nullable_cache
= res
903 # Return the not nullable version of the type
904 # Is the type is already not nullable, then self is returned.
906 # Note: this just remove the `nullable` notation, but the result can still contains null.
907 # For instance if `self isa MNullType` or self is a a formal type bounded by a nullable type.
908 fun as_notnullable
: MType
913 private var as_nullable_cache
: nullable MType = null
916 # The deph of the type seen as a tree.
923 # Formal types have a depth of 1.
929 # The length of the type seen as a tree.
936 # Formal types have a length of 1.
942 # Compute all the classdefs inherited/imported.
943 # The returned set contains:
944 # * the class definitions from `mmodule` and its imported modules
945 # * the class definitions of this type and its super-types
947 # This function is used mainly internally.
949 # REQUIRE: `not self.need_anchor`
950 fun collect_mclassdefs
(mmodule
: MModule): Set[MClassDef] is abstract
952 # Compute all the super-classes.
953 # This function is used mainly internally.
955 # REQUIRE: `not self.need_anchor`
956 fun collect_mclasses
(mmodule
: MModule): Set[MClass] is abstract
958 # Compute all the declared super-types.
959 # Super-types are returned as declared in the classdefs (verbatim).
960 # This function is used mainly internally.
962 # REQUIRE: `not self.need_anchor`
963 fun collect_mtypes
(mmodule
: MModule): Set[MClassType] is abstract
965 # Is the property in self for a given module
966 # This method does not filter visibility or whatever
968 # REQUIRE: `not self.need_anchor`
969 fun has_mproperty
(mmodule
: MModule, mproperty
: MProperty): Bool
971 assert not self.need_anchor
972 return self.collect_mclassdefs
(mmodule
).has
(mproperty
.intro_mclassdef
)
976 # A type based on a class.
978 # `MClassType` have properties (see `has_mproperty`).
982 # The associated class
985 redef fun model
do return self.mclass
.intro_mmodule
.model
987 private init(mclass
: MClass)
992 # The formal arguments of the type
993 # ENSURE: `result.length == self.mclass.arity`
994 var arguments
: Array[MType] = new Array[MType]
996 redef fun to_s
do return mclass
.to_s
998 redef fun need_anchor
do return false
1000 redef fun anchor_to
(mmodule
: MModule, anchor
: MClassType): MClassType
1002 return super.as(MClassType)
1005 redef fun resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule, cleanup_virtual
: Bool): MClassType do return self
1007 redef fun can_resolve_for
(mtype
, anchor
, mmodule
) do return true
1009 redef fun collect_mclassdefs
(mmodule
)
1011 assert not self.need_anchor
1012 var cache
= self.collect_mclassdefs_cache
1013 if not cache
.has_key
(mmodule
) then
1014 self.collect_things
(mmodule
)
1016 return cache
[mmodule
]
1019 redef fun collect_mclasses
(mmodule
)
1021 assert not self.need_anchor
1022 var cache
= self.collect_mclasses_cache
1023 if not cache
.has_key
(mmodule
) then
1024 self.collect_things
(mmodule
)
1026 return cache
[mmodule
]
1029 redef fun collect_mtypes
(mmodule
)
1031 assert not self.need_anchor
1032 var cache
= self.collect_mtypes_cache
1033 if not cache
.has_key
(mmodule
) then
1034 self.collect_things
(mmodule
)
1036 return cache
[mmodule
]
1039 # common implementation for `collect_mclassdefs`, `collect_mclasses`, and `collect_mtypes`.
1040 private fun collect_things
(mmodule
: MModule)
1042 var res
= new HashSet[MClassDef]
1043 var seen
= new HashSet[MClass]
1044 var types
= new HashSet[MClassType]
1045 seen
.add
(self.mclass
)
1046 var todo
= [self.mclass
]
1047 while not todo
.is_empty
do
1048 var mclass
= todo
.pop
1049 #print "process {mclass}"
1050 for mclassdef
in mclass
.mclassdefs
do
1051 if not mmodule
.in_importation
<= mclassdef
.mmodule
then continue
1052 #print " process {mclassdef}"
1054 for supertype
in mclassdef
.supertypes
do
1055 types
.add
(supertype
)
1056 var superclass
= supertype
.mclass
1057 if seen
.has
(superclass
) then continue
1058 #print " add {superclass}"
1059 seen
.add
(superclass
)
1060 todo
.add
(superclass
)
1064 collect_mclassdefs_cache
[mmodule
] = res
1065 collect_mclasses_cache
[mmodule
] = seen
1066 collect_mtypes_cache
[mmodule
] = types
1069 private var collect_mclassdefs_cache
: HashMap[MModule, Set[MClassDef]] = new HashMap[MModule, Set[MClassDef]]
1070 private var collect_mclasses_cache
: HashMap[MModule, Set[MClass]] = new HashMap[MModule, Set[MClass]]
1071 private var collect_mtypes_cache
: HashMap[MModule, Set[MClassType]] = new HashMap[MModule, Set[MClassType]]
1075 # A type based on a generic class.
1076 # A generic type a just a class with additional formal generic arguments.
1080 private init(mclass
: MClass, arguments
: Array[MType])
1083 assert self.mclass
.arity
== arguments
.length
1084 self.arguments
= arguments
1086 self.need_anchor
= false
1087 for t
in arguments
do
1088 if t
.need_anchor
then
1089 self.need_anchor
= true
1094 self.to_s
= "{mclass}[{arguments.join(", ")}]"
1097 # Recursively print the type of the arguments within brackets.
1098 # Example: `"Map[String, List[Int]]"`
1099 redef var to_s
: String
1101 redef var need_anchor
: Bool
1103 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1105 if not need_anchor
then return self
1106 assert can_resolve_for
(mtype
, anchor
, mmodule
)
1107 var types
= new Array[MType]
1108 for t
in arguments
do
1109 types
.add
(t
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
))
1111 return mclass
.get_mtype
(types
)
1114 redef fun can_resolve_for
(mtype
, anchor
, mmodule
)
1116 if not need_anchor
then return true
1117 for t
in arguments
do
1118 if not t
.can_resolve_for
(mtype
, anchor
, mmodule
) then return false
1127 for a
in self.arguments
do
1129 if d
> dmax
then dmax
= d
1137 for a
in self.arguments
do
1144 # A virtual formal type.
1148 # The property associated with the type.
1149 # Its the definitions of this property that determine the bound or the virtual type.
1150 var mproperty
: MProperty
1152 redef fun model
do return self.mproperty
.intro_mclassdef
.mmodule
.model
1154 # Lookup the bound for a given resolved_receiver
1155 # The result may be a other virtual type (or a parameter type)
1157 # The result is returned exactly as declared in the "type" property (verbatim).
1159 # In case of conflict, the method aborts.
1160 fun lookup_bound
(mmodule
: MModule, resolved_receiver
: MType): MType
1162 assert not resolved_receiver
.need_anchor
1163 var props
= self.mproperty
.lookup_definitions
(mmodule
, resolved_receiver
)
1164 if props
.is_empty
then
1166 else if props
.length
== 1 then
1167 return props
.first
.as(MVirtualTypeDef).bound
.as(not null)
1169 var types
= new ArraySet[MType]
1171 types
.add
(p
.as(MVirtualTypeDef).bound
.as(not null))
1173 if types
.length
== 1 then
1179 # Is the virtual type fixed for a given resolved_receiver?
1180 fun is_fixed
(mmodule
: MModule, resolved_receiver
: MType): Bool
1182 assert not resolved_receiver
.need_anchor
1183 var props
= self.mproperty
.lookup_definitions
(mmodule
, resolved_receiver
)
1184 if props
.is_empty
then
1188 if p
.as(MVirtualTypeDef).is_fixed
then return true
1193 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1195 assert can_resolve_for
(mtype
, anchor
, mmodule
)
1196 # self is a virtual type declared (or inherited) in mtype
1197 # The point of the function it to get the bound of the virtual type that make sense for mtype
1198 # But because mtype is maybe a virtual/formal type, we need to get a real receiver first
1199 #print "{class_name}: {self}/{mtype}/{anchor}?"
1200 var resolved_reciever
1201 if mtype
.need_anchor
then
1202 assert anchor
!= null
1203 resolved_reciever
= mtype
.resolve_for
(anchor
, null, mmodule
, true)
1205 resolved_reciever
= mtype
1207 # Now, we can get the bound
1208 var verbatim_bound
= lookup_bound
(mmodule
, resolved_reciever
)
1209 # The bound is exactly as declared in the "type" property, so we must resolve it again
1210 var res
= verbatim_bound
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1211 #print "{class_name}: {self}/{mtype}/{anchor} -> {self}/{resolved_reciever}/{anchor} -> {verbatim_bound}/{mtype}/{anchor} -> {res}"
1213 # What to return here? There is a bunch a special cases:
1214 # If 'cleanup_virtual' we must return the resolved type, since we cannot return self
1215 if cleanup_virtual
then return res
1216 # 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
1217 if resolved_reciever
isa MNullableType then resolved_reciever
= resolved_reciever
.mtype
1218 if resolved_reciever
.as(MClassType).mclass
.kind
== enum_kind
then return res
1219 # 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.
1220 if res
isa MVirtualType then return res
1221 # If we are final, just return the resolution
1222 if is_fixed
(mmodule
, resolved_reciever
) then return res
1223 # 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
1224 if res
isa MClassType and res
.mclass
.kind
== enum_kind
then return res
1225 # TODO: Add 'fixed' virtual type in the specification.
1226 # TODO: What if bound to a MParameterType?
1227 # Note that Nullable types can always be redefined by the non nullable version, so there is no specific case on it.
1229 # If anything apply, then `self' cannot be resolved, so return self
1233 redef fun can_resolve_for
(mtype
, anchor
, mmodule
)
1235 if mtype
.need_anchor
then
1236 assert anchor
!= null
1237 mtype
= mtype
.anchor_to
(mmodule
, anchor
)
1239 return mtype
.has_mproperty
(mmodule
, mproperty
)
1242 redef fun to_s
do return self.mproperty
.to_s
1244 init(mproperty
: MProperty)
1246 self.mproperty
= mproperty
1250 # The type associated the a formal parameter generic type of a class
1252 # Each parameter type is associated to a specific class.
1253 # It means that all refinements of a same class "share" the parameter type,
1254 # but that a generic subclass has its own parameter types.
1256 # However, in the sense of the meta-model, a parameter type of a class is
1257 # a valid type in a subclass. The "in the sense of the meta-model" is
1258 # important because, in the Nit language, the programmer cannot refers
1259 # directly to the parameter types of the super-classes.
1263 # fun e: E is abstract
1268 # In the class definition B[F], `F` is a valid type but `E` is not.
1269 # However, `self.e` is a valid method call, and the signature of `e` is
1272 # Note that parameter types are shared among class refinements.
1273 # Therefore parameter only have an internal name (see `to_s` for details).
1274 # TODO: Add a `name_for` to get better messages.
1275 class MParameterType
1278 # The generic class where the parameter belong
1281 redef fun model
do return self.mclass
.intro_mmodule
.model
1283 # The position of the parameter (0 for the first parameter)
1284 # FIXME: is `position` a better name?
1289 redef fun to_s
do return name
1291 # Resolve the bound for a given resolved_receiver
1292 # The result may be a other virtual type (or a parameter type)
1293 fun lookup_bound
(mmodule
: MModule, resolved_receiver
: MType): MType
1295 assert not resolved_receiver
.need_anchor
1296 var goalclass
= self.mclass
1297 var supertypes
= resolved_receiver
.collect_mtypes
(mmodule
)
1298 for t
in supertypes
do
1299 if t
.mclass
== goalclass
then
1300 # Yeah! c specialize goalclass with a "super `t'". So the question is what is the argument of f
1301 # FIXME: Here, we stop on the first goal. Should we check others and detect inconsistencies?
1302 var res
= t
.arguments
[self.rank
]
1309 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1311 assert can_resolve_for
(mtype
, anchor
, mmodule
)
1312 #print "{class_name}: {self}/{mtype}/{anchor}?"
1314 if mtype
isa MGenericType and mtype
.mclass
== self.mclass
then
1315 var res
= mtype
.arguments
[self.rank
]
1316 if anchor
!= null and res
.need_anchor
then
1317 # Maybe the result can be resolved more if are bound to a final class
1318 var r2
= res
.anchor_to
(mmodule
, anchor
)
1319 if r2
isa MClassType and r2
.mclass
.kind
== enum_kind
then return r2
1324 # self is a parameter type of mtype (or of a super-class of mtype)
1325 # The point of the function it to get the bound of the virtual type that make sense for mtype
1326 # But because mtype is maybe a virtual/formal type, we need to get a real receiver first
1327 # FIXME: What happend here is far from clear. Thus this part must be validated and clarified
1328 var resolved_receiver
1329 if mtype
.need_anchor
then
1330 assert anchor
!= null
1331 resolved_receiver
= mtype
.resolve_for
(anchor
.mclass
.mclass_type
, anchor
, mmodule
, true)
1333 resolved_receiver
= mtype
1335 if resolved_receiver
isa MNullableType then resolved_receiver
= resolved_receiver
.mtype
1336 if resolved_receiver
isa MParameterType then
1337 assert resolved_receiver
.mclass
== anchor
.mclass
1338 resolved_receiver
= anchor
.arguments
[resolved_receiver
.rank
]
1339 if resolved_receiver
isa MNullableType then resolved_receiver
= resolved_receiver
.mtype
1341 assert resolved_receiver
isa MClassType
1343 # Eh! The parameter is in the current class.
1344 # So we return the corresponding argument, no mater what!
1345 if resolved_receiver
.mclass
== self.mclass
then
1346 var res
= resolved_receiver
.arguments
[self.rank
]
1347 #print "{class_name}: {self}/{mtype}/{anchor} -> direct {res}"
1351 if resolved_receiver
.need_anchor
then
1352 assert anchor
!= null
1353 resolved_receiver
= resolved_receiver
.resolve_for
(anchor
, null, mmodule
, false)
1355 # Now, we can get the bound
1356 var verbatim_bound
= lookup_bound
(mmodule
, resolved_receiver
)
1357 # The bound is exactly as declared in the "type" property, so we must resolve it again
1358 var res
= verbatim_bound
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1360 #print "{class_name}: {self}/{mtype}/{anchor} -> indirect {res}"
1365 redef fun can_resolve_for
(mtype
, anchor
, mmodule
)
1367 if mtype
.need_anchor
then
1368 assert anchor
!= null
1369 mtype
= mtype
.anchor_to
(mmodule
, anchor
)
1371 return mtype
.collect_mclassdefs
(mmodule
).has
(mclass
.intro
)
1374 init(mclass
: MClass, rank
: Int, name
: String)
1376 self.mclass
= mclass
1382 # A type prefixed with "nullable"
1386 # The base type of the nullable type
1389 redef fun model
do return self.mtype
.model
1394 self.to_s
= "nullable {mtype}"
1397 redef var to_s
: String
1399 redef fun need_anchor
do return mtype
.need_anchor
1400 redef fun as_nullable
do return self
1401 redef fun as_notnullable
do return mtype
1402 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1404 var res
= self.mtype
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1405 return res
.as_nullable
1408 redef fun can_resolve_for
(mtype
, anchor
, mmodule
)
1410 return self.mtype
.can_resolve_for
(mtype
, anchor
, mmodule
)
1413 redef fun depth
do return self.mtype
.depth
1415 redef fun length
do return self.mtype
.length
1417 redef fun collect_mclassdefs
(mmodule
)
1419 assert not self.need_anchor
1420 return self.mtype
.collect_mclassdefs
(mmodule
)
1423 redef fun collect_mclasses
(mmodule
)
1425 assert not self.need_anchor
1426 return self.mtype
.collect_mclasses
(mmodule
)
1429 redef fun collect_mtypes
(mmodule
)
1431 assert not self.need_anchor
1432 return self.mtype
.collect_mtypes
(mmodule
)
1436 # The type of the only value null
1438 # The is only one null type per model, see `MModel::null_type`.
1441 redef var model
: Model
1442 protected init(model
: Model)
1446 redef fun to_s
do return "null"
1447 redef fun as_nullable
do return self
1448 redef fun need_anchor
do return false
1449 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
) do return self
1450 redef fun can_resolve_for
(mtype
, anchor
, mmodule
) do return true
1452 redef fun collect_mclassdefs
(mmodule
) do return new HashSet[MClassDef]
1454 redef fun collect_mclasses
(mmodule
) do return new HashSet[MClass]
1456 redef fun collect_mtypes
(mmodule
) do return new HashSet[MClassType]
1459 # A signature of a method
1463 # The each parameter (in order)
1464 var mparameters
: Array[MParameter]
1466 # The return type (null for a procedure)
1467 var return_mtype
: nullable MType
1472 var t
= self.return_mtype
1473 if t
!= null then dmax
= t
.depth
1474 for p
in mparameters
do
1475 var d
= p
.mtype
.depth
1476 if d
> dmax
then dmax
= d
1484 var t
= self.return_mtype
1485 if t
!= null then res
+= t
.length
1486 for p
in mparameters
do
1487 res
+= p
.mtype
.length
1492 # REQUIRE: 1 <= mparameters.count p -> p.is_vararg
1493 init(mparameters
: Array[MParameter], return_mtype
: nullable MType)
1495 var vararg_rank
= -1
1496 for i
in [0..mparameters
.length
[ do
1497 var parameter
= mparameters
[i
]
1498 if parameter
.is_vararg
then
1499 assert vararg_rank
== -1
1503 self.mparameters
= mparameters
1504 self.return_mtype
= return_mtype
1505 self.vararg_rank
= vararg_rank
1508 # The rank of the ellipsis (`...`) for vararg (starting from 0).
1509 # value is -1 if there is no vararg.
1510 # Example: for "(a: Int, b: Bool..., c: Char)" #-> vararg_rank=1
1511 var vararg_rank
: Int
1513 # The number or parameters
1514 fun arity
: Int do return mparameters
.length
1518 var b
= new FlatBuffer
1519 if not mparameters
.is_empty
then
1521 for i
in [0..mparameters
.length
[ do
1522 var mparameter
= mparameters
[i
]
1523 if i
> 0 then b
.append
(", ")
1524 b
.append
(mparameter
.name
)
1526 b
.append
(mparameter
.mtype
.to_s
)
1527 if mparameter
.is_vararg
then
1533 var ret
= self.return_mtype
1541 redef fun resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule, cleanup_virtual
: Bool): MSignature
1543 var params
= new Array[MParameter]
1544 for p
in self.mparameters
do
1545 params
.add
(p
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
))
1547 var ret
= self.return_mtype
1549 ret
= ret
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1551 var res
= new MSignature(params
, ret
)
1556 # A parameter in a signature
1560 # The name of the parameter
1561 redef var name
: String
1563 # The static type of the parameter
1566 # Is the parameter a vararg?
1569 init(name
: String, mtype
: MType, is_vararg
: Bool) do
1572 self.is_vararg
= is_vararg
1578 return "{name}: {mtype}..."
1580 return "{name}: {mtype}"
1584 fun resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule, cleanup_virtual
: Bool): MParameter
1586 if not self.mtype
.need_anchor
then return self
1587 var newtype
= self.mtype
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1588 var res
= new MParameter(self.name
, newtype
, self.is_vararg
)
1592 redef fun model
do return mtype
.model
1595 # A service (global property) that generalize method, attribute, etc.
1597 # `MProperty` are global to the model; it means that a `MProperty` is not bound
1598 # to a specific `MModule` nor a specific `MClass`.
1600 # A MProperty gather definitions (see `mpropdefs`) ; one for the introduction
1601 # and the other in subclasses and in refinements.
1603 # A `MProperty` is used to denotes services in polymorphic way (ie. independent
1604 # of any dynamic type).
1605 # For instance, a call site "x.foo" is associated to a `MProperty`.
1606 abstract class MProperty
1609 # The associated MPropDef subclass.
1610 # The two specialization hierarchy are symmetric.
1611 type MPROPDEF: MPropDef
1613 # The classdef that introduce the property
1614 # While a property is not bound to a specific module, or class,
1615 # the introducing mclassdef is used for naming and visibility
1616 var intro_mclassdef
: MClassDef
1618 # The (short) name of the property
1619 redef var name
: String
1621 # The canonical name of the property
1622 # Example: "owner::my_module::MyClass::my_method"
1623 fun full_name
: String
1625 return "{self.intro_mclassdef.mmodule.full_name}::{self.intro_mclassdef.mclass.name}::{name}"
1628 # The visibility of the property
1629 var visibility
: MVisibility
1631 init(intro_mclassdef
: MClassDef, name
: String, visibility
: MVisibility)
1633 self.intro_mclassdef
= intro_mclassdef
1635 self.visibility
= visibility
1636 intro_mclassdef
.intro_mproperties
.add
(self)
1637 var model
= intro_mclassdef
.mmodule
.model
1638 model
.mproperties_by_name
.add_one
(name
, self)
1639 model
.mproperties
.add
(self)
1642 # All definitions of the property.
1643 # The first is the introduction,
1644 # The other are redefinitions (in refinements and in subclasses)
1645 var mpropdefs
: Array[MPROPDEF] = new Array[MPROPDEF]
1647 # The definition that introduced the property
1648 # Warning: the introduction is the first `MPropDef` object
1649 # associated to self. If self is just created without having any
1650 # associated definition, this method will abort
1651 fun intro
: MPROPDEF do return mpropdefs
.first
1653 redef fun model
do return intro
.model
1656 redef fun to_s
do return name
1658 # Return the most specific property definitions defined or inherited by a type.
1659 # The selection knows that refinement is stronger than specialization;
1660 # however, in case of conflict more than one property are returned.
1661 # If mtype does not know mproperty then an empty array is returned.
1663 # If you want the really most specific property, then look at `lookup_first_definition`
1664 fun lookup_definitions
(mmodule
: MModule, mtype
: MType): Array[MPROPDEF]
1666 assert not mtype
.need_anchor
1667 mtype
= mtype
.as_notnullable
1669 var cache
= self.lookup_definitions_cache
[mmodule
, mtype
]
1670 if cache
!= null then return cache
1672 #print "select prop {mproperty} for {mtype} in {self}"
1673 # First, select all candidates
1674 var candidates
= new Array[MPROPDEF]
1675 for mpropdef
in self.mpropdefs
do
1676 # If the definition is not imported by the module, then skip
1677 if not mmodule
.in_importation
<= mpropdef
.mclassdef
.mmodule
then continue
1678 # If the definition is not inherited by the type, then skip
1679 if not mtype
.is_subtype
(mmodule
, null, mpropdef
.mclassdef
.bound_mtype
) then continue
1681 candidates
.add
(mpropdef
)
1683 # Fast track for only one candidate
1684 if candidates
.length
<= 1 then
1685 self.lookup_definitions_cache
[mmodule
, mtype
] = candidates
1689 # Second, filter the most specific ones
1690 return select_most_specific
(mmodule
, candidates
)
1693 private var lookup_definitions_cache
: HashMap2[MModule, MType, Array[MPROPDEF]] = new HashMap2[MModule, MType, Array[MPROPDEF]]
1695 # Return the most specific property definitions inherited by a type.
1696 # The selection knows that refinement is stronger than specialization;
1697 # however, in case of conflict more than one property are returned.
1698 # If mtype does not know mproperty then an empty array is returned.
1700 # If you want the really most specific property, then look at `lookup_next_definition`
1702 # FIXME: Move to `MPropDef`?
1703 fun lookup_super_definitions
(mmodule
: MModule, mtype
: MType): Array[MPROPDEF]
1705 assert not mtype
.need_anchor
1706 mtype
= mtype
.as_notnullable
1708 # First, select all candidates
1709 var candidates
= new Array[MPROPDEF]
1710 for mpropdef
in self.mpropdefs
do
1711 # If the definition is not imported by the module, then skip
1712 if not mmodule
.in_importation
<= mpropdef
.mclassdef
.mmodule
then continue
1713 # If the definition is not inherited by the type, then skip
1714 if not mtype
.is_subtype
(mmodule
, null, mpropdef
.mclassdef
.bound_mtype
) then continue
1715 # If the definition is defined by the type, then skip (we want the super, so e skip the current)
1716 if mtype
== mpropdef
.mclassdef
.bound_mtype
and mmodule
== mpropdef
.mclassdef
.mmodule
then continue
1718 candidates
.add
(mpropdef
)
1720 # Fast track for only one candidate
1721 if candidates
.length
<= 1 then return candidates
1723 # Second, filter the most specific ones
1724 return select_most_specific
(mmodule
, candidates
)
1727 # Return an array containing olny the most specific property definitions
1728 # This is an helper function for `lookup_definitions` and `lookup_super_definitions`
1729 private fun select_most_specific
(mmodule
: MModule, candidates
: Array[MPROPDEF]): Array[MPROPDEF]
1731 var res
= new Array[MPROPDEF]
1732 for pd1
in candidates
do
1733 var cd1
= pd1
.mclassdef
1736 for pd2
in candidates
do
1737 if pd2
== pd1
then continue # do not compare with self!
1738 var cd2
= pd2
.mclassdef
1740 if c2
.mclass_type
== c1
.mclass_type
then
1741 if cd2
.mmodule
.in_importation
< cd1
.mmodule
then
1742 # cd2 refines cd1; therefore we skip pd1
1746 else if cd2
.bound_mtype
.is_subtype
(mmodule
, null, cd1
.bound_mtype
) and cd2
.bound_mtype
!= cd1
.bound_mtype
then
1747 # cd2 < cd1; therefore we skip pd1
1756 if res
.is_empty
then
1757 print
"All lost! {candidates.join(", ")}"
1758 # FIXME: should be abort!
1763 # Return the most specific definition in the linearization of `mtype`.
1765 # If you want to know the next properties in the linearization,
1766 # look at `MPropDef::lookup_next_definition`.
1768 # FIXME: the linearisation is still unspecified
1770 # REQUIRE: `not mtype.need_anchor`
1771 # REQUIRE: `mtype.has_mproperty(mmodule, self)`
1772 fun lookup_first_definition
(mmodule
: MModule, mtype
: MType): MPROPDEF
1774 assert mtype
.has_mproperty
(mmodule
, self)
1775 return lookup_all_definitions
(mmodule
, mtype
).first
1778 # Return all definitions in a linearisation order
1779 # Most speficic first, most general last
1780 fun lookup_all_definitions
(mmodule
: MModule, mtype
: MType): Array[MPROPDEF]
1782 assert not mtype
.need_anchor
1783 mtype
= mtype
.as_notnullable
1785 var cache
= self.lookup_all_definitions_cache
[mmodule
, mtype
]
1786 if cache
!= null then return cache
1788 #print "select prop {mproperty} for {mtype} in {self}"
1789 # First, select all candidates
1790 var candidates
= new Array[MPROPDEF]
1791 for mpropdef
in self.mpropdefs
do
1792 # If the definition is not imported by the module, then skip
1793 if not mmodule
.in_importation
<= mpropdef
.mclassdef
.mmodule
then continue
1794 # If the definition is not inherited by the type, then skip
1795 if not mtype
.is_subtype
(mmodule
, null, mpropdef
.mclassdef
.bound_mtype
) then continue
1797 candidates
.add
(mpropdef
)
1799 # Fast track for only one candidate
1800 if candidates
.length
<= 1 then
1801 self.lookup_all_definitions_cache
[mmodule
, mtype
] = candidates
1805 mmodule
.linearize_mpropdefs
(candidates
)
1806 candidates
= candidates
.reversed
1807 self.lookup_all_definitions_cache
[mmodule
, mtype
] = candidates
1811 private var lookup_all_definitions_cache
: HashMap2[MModule, MType, Array[MPROPDEF]] = new HashMap2[MModule, MType, Array[MPROPDEF]]
1818 redef type MPROPDEF: MMethodDef
1820 init(intro_mclassdef
: MClassDef, name
: String, visibility
: MVisibility)
1825 # Is the property defined at the top_level of the module?
1826 # Currently such a property are stored in `Object`
1827 var is_toplevel
: Bool = false is writable
1829 # Is the property a constructor?
1830 # Warning, this property can be inherited by subclasses with or without being a constructor
1831 # therefore, you should use `is_init_for` the verify if the property is a legal constructor for a given class
1832 var is_init
: Bool = false is writable
1834 # The constructor is a (the) root init with empty signature but a set of initializers
1835 var is_root_init
: Bool = false is writable
1837 # The the property a 'new' contructor?
1838 var is_new
: Bool = false is writable
1840 # Is the property a legal constructor for a given class?
1841 # As usual, visibility is not considered.
1842 # FIXME not implemented
1843 fun is_init_for
(mclass
: MClass): Bool
1849 # A global attribute
1853 redef type MPROPDEF: MAttributeDef
1855 init(intro_mclassdef
: MClassDef, name
: String, visibility
: MVisibility)
1861 # A global virtual type
1862 class MVirtualTypeProp
1865 redef type MPROPDEF: MVirtualTypeDef
1867 init(intro_mclassdef
: MClassDef, name
: String, visibility
: MVisibility)
1872 # The formal type associated to the virtual type property
1873 var mvirtualtype
: MVirtualType = new MVirtualType(self)
1876 # A definition of a property (local property)
1878 # Unlike `MProperty`, a `MPropDef` is a local definition that belong to a
1879 # specific class definition (which belong to a specific module)
1880 abstract class MPropDef
1883 # The associated `MProperty` subclass.
1884 # the two specialization hierarchy are symmetric
1885 type MPROPERTY: MProperty
1888 type MPROPDEF: MPropDef
1890 # The origin of the definition
1891 var location
: Location
1893 # The class definition where the property definition is
1894 var mclassdef
: MClassDef
1896 # The associated global property
1897 var mproperty
: MPROPERTY
1899 init(mclassdef
: MClassDef, mproperty
: MPROPERTY, location
: Location)
1901 self.mclassdef
= mclassdef
1902 self.mproperty
= mproperty
1903 self.location
= location
1904 mclassdef
.mpropdefs
.add
(self)
1905 mproperty
.mpropdefs
.add
(self)
1906 self.to_s
= "{mclassdef}#{mproperty}"
1909 # Actually the name of the `mproperty`
1910 redef fun name
do return mproperty
.name
1912 redef fun model
do return mclassdef
.model
1914 # Internal name combining the module, the class and the property
1915 # Example: "mymodule#MyClass#mymethod"
1916 redef var to_s
: String
1918 # Is self the definition that introduce the property?
1919 fun is_intro
: Bool do return mproperty
.intro
== self
1921 # Return the next definition in linearization of `mtype`.
1923 # This method is used to determine what method is called by a super.
1925 # REQUIRE: `not mtype.need_anchor`
1926 fun lookup_next_definition
(mmodule
: MModule, mtype
: MType): MPROPDEF
1928 assert not mtype
.need_anchor
1930 var mpropdefs
= self.mproperty
.lookup_all_definitions
(mmodule
, mtype
)
1931 var i
= mpropdefs
.iterator
1932 while i
.is_ok
and i
.item
!= self do i
.next
1933 assert has_property
: i
.is_ok
1935 assert has_next_property
: i
.is_ok
1940 # A local definition of a method
1944 redef type MPROPERTY: MMethod
1945 redef type MPROPDEF: MMethodDef
1947 init(mclassdef
: MClassDef, mproperty
: MPROPERTY, location
: Location)
1952 # The signature attached to the property definition
1953 var msignature
: nullable MSignature = null is writable
1955 # The signature attached to the `new` call on a root-init
1956 # This is a concatenation of the signatures of the initializers
1958 # REQUIRE `mproperty.is_root_init == (new_msignature != null)`
1959 var new_msignature
: nullable MSignature = null is writable
1961 # List of initialisers to call in root-inits
1963 # They could be setters or attributes
1965 # REQUIRE `mproperty.is_root_init == (new_msignature != null)`
1966 var initializers
= new Array[MProperty]
1968 # Is the method definition abstract?
1969 var is_abstract
: Bool = false is writable
1971 # Is the method definition intern?
1972 var is_intern
= false is writable
1974 # Is the method definition extern?
1975 var is_extern
= false is writable
1978 # A local definition of an attribute
1982 redef type MPROPERTY: MAttribute
1983 redef type MPROPDEF: MAttributeDef
1985 init(mclassdef
: MClassDef, mproperty
: MPROPERTY, location
: Location)
1990 # The static type of the attribute
1991 var static_mtype
: nullable MType = null is writable
1994 # A local definition of a virtual type
1995 class MVirtualTypeDef
1998 redef type MPROPERTY: MVirtualTypeProp
1999 redef type MPROPDEF: MVirtualTypeDef
2001 init(mclassdef
: MClassDef, mproperty
: MPROPERTY, location
: Location)
2006 # The bound of the virtual type
2007 var bound
: nullable MType = null is writable
2009 # Is the bound fixed?
2010 var is_fixed
= false is writable
2017 # * `interface_kind`
2021 # Note this class is basically an enum.
2022 # FIXME: use a real enum once user-defined enums are available
2024 redef var to_s
: String
2026 # Is a constructor required?
2028 private init(s
: String, need_init
: Bool)
2031 self.need_init
= need_init
2034 # Can a class of kind `self` specializes a class of kine `other`?
2035 fun can_specialize
(other
: MClassKind): Bool
2037 if other
== interface_kind
then return true # everybody can specialize interfaces
2038 if self == interface_kind
or self == enum_kind
then
2039 # no other case for interfaces
2041 else if self == extern_kind
then
2042 # only compatible with themselve
2043 return self == other
2044 else if other
== enum_kind
or other
== extern_kind
then
2045 # abstract_kind and concrete_kind are incompatible
2048 # remain only abstract_kind and concrete_kind
2053 fun abstract_kind
: MClassKind do return once
new MClassKind("abstract class", true)
2054 fun concrete_kind
: MClassKind do return once
new MClassKind("class", true)
2055 fun interface_kind
: MClassKind do return once
new MClassKind("interface", false)
2056 fun enum_kind
: MClassKind do return once
new MClassKind("enum", false)
2057 fun extern_kind
: MClassKind do return once
new MClassKind("extern class", false)