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
367 # Each generic formal parameters in order.
368 # is empty if the class is not generic
369 var mparameters
= new Array[MParameterType]
371 # The kind of the class (interface, abstract class, etc.)
372 # In Nit, the kind of a class cannot evolve in refinements
375 # The visibility of the class
376 # In Nit, the visibility of a class cannot evolve in refinements
377 var visibility
: MVisibility
379 init(intro_mmodule
: MModule, name
: String, parameter_names
: nullable Array[String], kind
: MClassKind, visibility
: MVisibility)
381 self.intro_mmodule
= intro_mmodule
383 if parameter_names
== null then
386 self.arity
= parameter_names
.length
389 self.visibility
= visibility
390 intro_mmodule
.intro_mclasses
.add
(self)
391 var model
= intro_mmodule
.model
392 model
.mclasses_by_name
.add_one
(name
, self)
393 model
.mclasses
.add
(self)
395 # Create the formal parameter types
397 assert parameter_names
!= null
398 var mparametertypes
= new Array[MParameterType]
399 for i
in [0..arity
[ do
400 var mparametertype
= new MParameterType(self, i
, parameter_names
[i
])
401 mparametertypes
.add
(mparametertype
)
403 self.mparameters
= mparametertypes
404 var mclass_type
= new MGenericType(self, mparametertypes
)
405 self.mclass_type
= mclass_type
406 self.get_mtype_cache
.add
(mclass_type
)
408 self.mclass_type
= new MClassType(self)
412 redef fun model
do return intro_mmodule
.model
414 # All class definitions (introduction and refinements)
415 var mclassdefs
= new Array[MClassDef]
418 redef fun to_s
do return self.name
420 # The definition that introduced the class
421 # Warning: the introduction is the first `MClassDef` object associated
422 # to self. If self is just created without having any associated
423 # definition, this method will abort
426 assert has_a_first_definition
: not mclassdefs
.is_empty
427 return mclassdefs
.first
430 # Return the class `self` in the class hierarchy of the module `mmodule`.
432 # SEE: `MModule::flatten_mclass_hierarchy`
433 # REQUIRE: `mmodule.has_mclass(self)`
434 fun in_hierarchy
(mmodule
: MModule): POSetElement[MClass]
436 return mmodule
.flatten_mclass_hierarchy
[self]
439 # The principal static type of the class.
441 # For non-generic class, mclass_type is the only `MClassType` based
444 # For a generic class, the arguments are the formal parameters.
445 # i.e.: for the class Array[E:Object], the `mclass_type` is Array[E].
446 # If you want Array[Object] the see `MClassDef::bound_mtype`
448 # For generic classes, the mclass_type is also the way to get a formal
449 # generic parameter type.
451 # To get other types based on a generic class, see `get_mtype`.
453 # ENSURE: `mclass_type.mclass == self`
454 var mclass_type
: MClassType
456 # Return a generic type based on the class
457 # Is the class is not generic, then the result is `mclass_type`
459 # REQUIRE: `mtype_arguments.length == self.arity`
460 fun get_mtype
(mtype_arguments
: Array[MType]): MClassType
462 assert mtype_arguments
.length
== self.arity
463 if self.arity
== 0 then return self.mclass_type
464 for t
in self.get_mtype_cache
do
465 if t
.arguments
== mtype_arguments
then
469 var res
= new MGenericType(self, mtype_arguments
)
470 self.get_mtype_cache
.add res
474 private var get_mtype_cache
= new Array[MGenericType]
478 # A definition (an introduction or a refinement) of a class in a module
480 # A `MClassDef` is associated with an explicit (or almost) definition of a
481 # class. Unlike `MClass`, a `MClassDef` is a local definition that belong to
482 # a specific class and a specific module, and contains declarations like super-classes
485 # It is the class definitions that are the backbone of most things in the model:
486 # ClassDefs are defined with regard with other classdefs.
487 # Refinement and specialization are combined to produce a big poset called the `Model::mclassdef_hierarchy`.
489 # Moreover, the extension and the intention of types is defined by looking at the MClassDefs.
493 # The module where the definition is
496 # The associated `MClass`
499 # The bounded type associated to the mclassdef
501 # For a non-generic class, `bound_mtype` and `mclass.mclass_type`
505 # For the classdef Array[E: Object], the bound_mtype is Array[Object].
506 # If you want Array[E], then see `mclass.mclass_type`
508 # ENSURE: `bound_mtype.mclass == self.mclass`
509 var bound_mtype
: MClassType
511 # The origin of the definition
512 var location
: Location
514 # Internal name combining the module and the class
515 # Example: "mymodule#MyClass"
516 redef var to_s
: String
518 init(mmodule
: MModule, bound_mtype
: MClassType, location
: Location)
520 self.bound_mtype
= bound_mtype
521 self.mmodule
= mmodule
522 self.mclass
= bound_mtype
.mclass
523 self.location
= location
524 mmodule
.mclassdefs
.add
(self)
525 mclass
.mclassdefs
.add
(self)
526 self.to_s
= "{mmodule}#{mclass}"
529 # Actually the name of the `mclass`
530 redef fun name
do return mclass
.name
532 redef fun model
do return mmodule
.model
534 # All declared super-types
535 # FIXME: quite ugly but not better idea yet
536 var supertypes
= new Array[MClassType]
538 # Register some super-types for the class (ie "super SomeType")
540 # The hierarchy must not already be set
541 # REQUIRE: `self.in_hierarchy == null`
542 fun set_supertypes
(supertypes
: Array[MClassType])
544 assert unique_invocation
: self.in_hierarchy
== null
545 var mmodule
= self.mmodule
546 var model
= mmodule
.model
547 var mtype
= self.bound_mtype
549 for supertype
in supertypes
do
550 self.supertypes
.add
(supertype
)
552 # Register in full_type_specialization_hierarchy
553 model
.full_mtype_specialization_hierarchy
.add_edge
(mtype
, supertype
)
554 # Register in intro_type_specialization_hierarchy
555 if mclass
.intro_mmodule
== mmodule
and supertype
.mclass
.intro_mmodule
== mmodule
then
556 model
.intro_mtype_specialization_hierarchy
.add_edge
(mtype
, supertype
)
562 # Collect the super-types (set by set_supertypes) to build the hierarchy
564 # This function can only invoked once by class
565 # REQUIRE: `self.in_hierarchy == null`
566 # ENSURE: `self.in_hierarchy != null`
569 assert unique_invocation
: self.in_hierarchy
== null
570 var model
= mmodule
.model
571 var res
= model
.mclassdef_hierarchy
.add_node
(self)
572 self.in_hierarchy
= res
573 var mtype
= self.bound_mtype
575 # Here we need to connect the mclassdef to its pairs in the mclassdef_hierarchy
576 # The simpliest way is to attach it to collect_mclassdefs
577 for mclassdef
in mtype
.collect_mclassdefs
(mmodule
) do
578 res
.poset
.add_edge
(self, mclassdef
)
582 # The view of the class definition in `mclassdef_hierarchy`
583 var in_hierarchy
: nullable POSetElement[MClassDef] = null
585 # Is the definition the one that introduced `mclass`?
586 fun is_intro
: Bool do return mclass
.intro
== self
588 # All properties introduced by the classdef
589 var intro_mproperties
= new Array[MProperty]
591 # All property definitions in the class (introductions and redefinitions)
592 var mpropdefs
= new Array[MPropDef]
595 # A global static type
597 # MType are global to the model; it means that a `MType` is not bound to a
598 # specific `MModule`.
599 # This characteristic helps the reasoning about static types in a program
600 # since a single `MType` object always denote the same type.
602 # However, because a `MType` is global, it does not really have properties
603 # nor have subtypes to a hierarchy since the property and the class hierarchy
604 # depends of a module.
605 # Moreover, virtual types an formal generic parameter types also depends on
606 # a receiver to have sense.
608 # Therefore, most method of the types require a module and an anchor.
609 # The module is used to know what are the classes and the specialization
611 # The anchor is used to know what is the bound of the virtual types and formal
612 # generic parameter types.
614 # MType are not directly usable to get properties. See the `anchor_to` method
615 # and the `MClassType` class.
617 # FIXME: the order of the parameters is not the best. We mus pick on from:
618 # * foo(mmodule, anchor, othertype)
619 # * foo(othertype, anchor, mmodule)
620 # * foo(anchor, mmodule, othertype)
621 # * foo(othertype, mmodule, anchor)
625 redef fun name
do return to_s
627 # Return true if `self` is an subtype of `sup`.
628 # The typing is done using the standard typing policy of Nit.
630 # REQUIRE: `anchor == null implies not self.need_anchor and not sup.need_anchor`
631 # REQUIRE: `anchor != null implies self.can_resolve_for(anchor, null, mmodule) and sup.can_resolve_for(anchor, null, mmodule)`
632 fun is_subtype
(mmodule
: MModule, anchor
: nullable MClassType, sup
: MType): Bool
635 if sub
== sup
then return true
636 if anchor
== null then
637 assert not sub
.need_anchor
638 assert not sup
.need_anchor
640 assert sub
.can_resolve_for
(anchor
, null, mmodule
)
641 assert sup
.can_resolve_for
(anchor
, null, mmodule
)
644 # First, resolve the formal types to a common version in the receiver
645 # The trick here is that fixed formal type will be associated to the bound
646 # And unfixed formal types will be associated to a canonical formal type.
647 if sub
isa MParameterType or sub
isa MVirtualType then
648 assert anchor
!= null
649 sub
= sub
.resolve_for
(anchor
.mclass
.mclass_type
, anchor
, mmodule
, false)
651 if sup
isa MParameterType or sup
isa MVirtualType then
652 assert anchor
!= null
653 sup
= sup
.resolve_for
(anchor
.mclass
.mclass_type
, anchor
, mmodule
, false)
656 # Does `sup` accept null or not?
657 # Discard the nullable marker if it exists
658 var sup_accept_null
= false
659 if sup
isa MNullableType then
660 sup_accept_null
= true
662 else if sup
isa MNullType then
663 sup_accept_null
= true
666 # Can `sub` provide null or not?
667 # Thus we can match with `sup_accept_null`
668 # Also discard the nullable marker if it exists
669 if sub
isa MNullableType then
670 if not sup_accept_null
then return false
672 else if sub
isa MNullType then
673 return sup_accept_null
675 # Now the case of direct null and nullable is over.
677 # A unfixed formal type can only accept itself
678 if sup
isa MParameterType or sup
isa MVirtualType then
682 # If `sub` is a formal type, then it is accepted if its bound is accepted
683 if sub
isa MParameterType or sub
isa MVirtualType then
684 assert anchor
!= null
685 sub
= sub
.anchor_to
(mmodule
, anchor
)
687 # Manage the second layer of null/nullable
688 if sub
isa MNullableType then
689 if not sup_accept_null
then return false
691 else if sub
isa MNullType then
692 return sup_accept_null
696 assert sub
isa MClassType # It is the only remaining type
698 if sup
isa MNullType then
699 # `sup` accepts only null
703 assert sup
isa MClassType # It is the only remaining type
705 # Now both are MClassType, we need to dig
707 if sub
== sup
then return true
709 if anchor
== null then anchor
= sub
# UGLY: any anchor will work
710 var resolved_sub
= sub
.anchor_to
(mmodule
, anchor
)
711 var res
= resolved_sub
.collect_mclasses
(mmodule
).has
(sup
.mclass
)
712 if res
== false then return false
713 if not sup
isa MGenericType then return true
714 var sub2
= sub
.supertype_to
(mmodule
, anchor
, sup
.mclass
)
715 assert sub2
.mclass
== sup
.mclass
716 for i
in [0..sup
.mclass
.arity
[ do
717 var sub_arg
= sub2
.arguments
[i
]
718 var sup_arg
= sup
.arguments
[i
]
719 res
= sub_arg
.is_subtype
(mmodule
, anchor
, sup_arg
)
720 if res
== false then return false
725 # The base class type on which self is based
727 # This base type is used to get property (an internally to perform
728 # unsafe type comparison).
730 # Beware: some types (like null) are not based on a class thus this
733 # Basically, this function transform the virtual types and parameter
734 # types to their bounds.
738 # class B super A end
740 # class Y super X end
748 # Map[T,U] anchor_to H #-> Map[B,Y]
750 # Explanation of the example:
751 # In H, T is set to B, because "H super G[B]", and U is bound to Y,
752 # because "redef type U: Y". Therefore, Map[T, U] is bound to
755 # ENSURE: `not self.need_anchor implies result == self`
756 # ENSURE: `not result.need_anchor`
757 fun anchor_to
(mmodule
: MModule, anchor
: MClassType): MType
759 if not need_anchor
then return self
760 assert not anchor
.need_anchor
761 # Just resolve to the anchor and clear all the virtual types
762 var res
= self.resolve_for
(anchor
, null, mmodule
, true)
763 assert not res
.need_anchor
767 # Does `self` contain a virtual type or a formal generic parameter type?
768 # In order to remove those types, you usually want to use `anchor_to`.
769 fun need_anchor
: Bool do return true
771 # Return the supertype when adapted to a class.
773 # In Nit, for each super-class of a type, there is a equivalent super-type.
777 # class H[V] super G[V, Bool] end
778 # H[Int] supertype_to G #-> G[Int, Bool]
780 # REQUIRE: `super_mclass` is a super-class of `self`
781 # REQUIRE: `self.need_anchor implies anchor != null and self.can_resolve_for(anchor, null, mmodule)`
782 # ENSURE: `result.mclass = super_mclass`
783 fun supertype_to
(mmodule
: MModule, anchor
: nullable MClassType, super_mclass
: MClass): MClassType
785 if super_mclass
.arity
== 0 then return super_mclass
.mclass_type
786 if self isa MClassType and self.mclass
== super_mclass
then return self
788 if self.need_anchor
then
789 assert anchor
!= null
790 resolved_self
= self.anchor_to
(mmodule
, anchor
)
794 var supertypes
= resolved_self
.collect_mtypes
(mmodule
)
795 for supertype
in supertypes
do
796 if supertype
.mclass
== super_mclass
then
797 # FIXME: Here, we stop on the first goal. Should we check others and detect inconsistencies?
798 return supertype
.resolve_for
(self, anchor
, mmodule
, false)
804 # Replace formals generic types in self with resolved values in `mtype`
805 # If `cleanup_virtual` is true, then virtual types are also replaced
808 # This function returns self if `need_anchor` is false.
813 # class H[F] super G[F] end
816 # * Array[E].resolve_for(H[Int]) #-> Array[Int]
817 # * Array[E].resolve_for(G[Z], X[Int]) #-> Array[Z]
819 # Explanation of the example:
820 # * Array[E].need_anchor is true because there is a formal generic parameter type E
821 # * E makes sense for H[Int] because E is a formal parameter of G and H specialize G
822 # * Since "H[F] super G[F]", E is in fact F for H
823 # * More specifically, in H[Int], E is Int
824 # * So, in H[Int], Array[E] is Array[Int]
826 # This function is mainly used to inherit a signature.
827 # Because, unlike `anchor_to`, we do not want a full resolution of
828 # a type but only an adapted version of it.
833 # fun foo(e:E):E is abstract
835 # class B super A[Int] end
837 # The signature on foo is (e: E): E
838 # If we resolve the signature for B, we get (e:Int):Int
843 # fun foo(e:E) is abstract
847 # fun bar do a.foo(x) # <- x is here
850 # The first question is: is foo available on `a`?
852 # The static type of a is `A[Array[F]]`, that is an open type.
853 # in order to find a method `foo`, whe must look at a resolved type.
855 # A[Array[F]].anchor_to(B[nullable Object]) #-> A[Array[nullable Object]]
857 # the method `foo` exists in `A[Array[nullable Object]]`, therefore `foo` exists for `a`.
859 # The next question is: what is the accepted types for `x`?
861 # the signature of `foo` is `foo(e:E)`, thus we must resolve the type E
863 # E.resolve_for(A[Array[F]],B[nullable Object]) #-> Array[F]
865 # The resolution can be done because `E` make sense for the class A (see `can_resolve_for`)
867 # FIXME: the parameter `cleanup_virtual` is just a bad idea, but having
868 # two function instead of one seems also to be a bad idea.
870 # REQUIRE: `can_resolve_for(mtype, anchor, mmodule)`
871 # ENSURE: `not self.need_anchor implies result == self`
872 fun resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule, cleanup_virtual
: Bool): MType is abstract
874 # Can the type be resolved?
876 # In order to resolve open types, the formal types must make sence.
885 # * E.can_resolve_for(A[Int]) #-> true, E make sense in A
886 # * E.can_resolve_for(B[Int]) #-> false, E does not make sense in B
887 # * B[E].can_resolve_for(A[F], B[Object]) #-> true,
888 # B[E] is a red hearing only the E is important,
891 # REQUIRE: `anchor != null implies not anchor.need_anchor`
892 # REQUIRE: `mtype.need_anchor implies anchor != null and mtype.can_resolve_for(anchor, null, mmodule)`
893 # ENSURE: `not self.need_anchor implies result == true`
894 fun can_resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule): Bool is abstract
896 # Return the nullable version of the type
897 # If the type is already nullable then self is returned
898 fun as_nullable
: MType
900 var res
= self.as_nullable_cache
901 if res
!= null then return res
902 res
= new MNullableType(self)
903 self.as_nullable_cache
= res
907 # Return the not nullable version of the type
908 # Is the type is already not nullable, then self is returned.
910 # Note: this just remove the `nullable` notation, but the result can still contains null.
911 # For instance if `self isa MNullType` or self is a formal type bounded by a nullable type.
912 fun as_notnullable
: MType
917 private var as_nullable_cache
: nullable MType = null
920 # The depth of the type seen as a tree.
927 # Formal types have a depth of 1.
933 # The length of the type seen as a tree.
940 # Formal types have a length of 1.
946 # Compute all the classdefs inherited/imported.
947 # The returned set contains:
948 # * the class definitions from `mmodule` and its imported modules
949 # * the class definitions of this type and its super-types
951 # This function is used mainly internally.
953 # REQUIRE: `not self.need_anchor`
954 fun collect_mclassdefs
(mmodule
: MModule): Set[MClassDef] is abstract
956 # Compute all the super-classes.
957 # This function is used mainly internally.
959 # REQUIRE: `not self.need_anchor`
960 fun collect_mclasses
(mmodule
: MModule): Set[MClass] is abstract
962 # Compute all the declared super-types.
963 # Super-types are returned as declared in the classdefs (verbatim).
964 # This function is used mainly internally.
966 # REQUIRE: `not self.need_anchor`
967 fun collect_mtypes
(mmodule
: MModule): Set[MClassType] is abstract
969 # Is the property in self for a given module
970 # This method does not filter visibility or whatever
972 # REQUIRE: `not self.need_anchor`
973 fun has_mproperty
(mmodule
: MModule, mproperty
: MProperty): Bool
975 assert not self.need_anchor
976 return self.collect_mclassdefs
(mmodule
).has
(mproperty
.intro_mclassdef
)
980 # A type based on a class.
982 # `MClassType` have properties (see `has_mproperty`).
986 # The associated class
989 redef fun model
do return self.mclass
.intro_mmodule
.model
991 private init(mclass
: MClass)
996 # The formal arguments of the type
997 # ENSURE: `result.length == self.mclass.arity`
998 var arguments
= new Array[MType]
1000 redef fun to_s
do return mclass
.to_s
1002 redef fun need_anchor
do return false
1004 redef fun anchor_to
(mmodule
: MModule, anchor
: MClassType): MClassType
1006 return super.as(MClassType)
1009 redef fun resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule, cleanup_virtual
: Bool): MClassType do return self
1011 redef fun can_resolve_for
(mtype
, anchor
, mmodule
) do return true
1013 redef fun collect_mclassdefs
(mmodule
)
1015 assert not self.need_anchor
1016 var cache
= self.collect_mclassdefs_cache
1017 if not cache
.has_key
(mmodule
) then
1018 self.collect_things
(mmodule
)
1020 return cache
[mmodule
]
1023 redef fun collect_mclasses
(mmodule
)
1025 assert not self.need_anchor
1026 var cache
= self.collect_mclasses_cache
1027 if not cache
.has_key
(mmodule
) then
1028 self.collect_things
(mmodule
)
1030 return cache
[mmodule
]
1033 redef fun collect_mtypes
(mmodule
)
1035 assert not self.need_anchor
1036 var cache
= self.collect_mtypes_cache
1037 if not cache
.has_key
(mmodule
) then
1038 self.collect_things
(mmodule
)
1040 return cache
[mmodule
]
1043 # common implementation for `collect_mclassdefs`, `collect_mclasses`, and `collect_mtypes`.
1044 private fun collect_things
(mmodule
: MModule)
1046 var res
= new HashSet[MClassDef]
1047 var seen
= new HashSet[MClass]
1048 var types
= new HashSet[MClassType]
1049 seen
.add
(self.mclass
)
1050 var todo
= [self.mclass
]
1051 while not todo
.is_empty
do
1052 var mclass
= todo
.pop
1053 #print "process {mclass}"
1054 for mclassdef
in mclass
.mclassdefs
do
1055 if not mmodule
.in_importation
<= mclassdef
.mmodule
then continue
1056 #print " process {mclassdef}"
1058 for supertype
in mclassdef
.supertypes
do
1059 types
.add
(supertype
)
1060 var superclass
= supertype
.mclass
1061 if seen
.has
(superclass
) then continue
1062 #print " add {superclass}"
1063 seen
.add
(superclass
)
1064 todo
.add
(superclass
)
1068 collect_mclassdefs_cache
[mmodule
] = res
1069 collect_mclasses_cache
[mmodule
] = seen
1070 collect_mtypes_cache
[mmodule
] = types
1073 private var collect_mclassdefs_cache
= new HashMap[MModule, Set[MClassDef]]
1074 private var collect_mclasses_cache
= new HashMap[MModule, Set[MClass]]
1075 private var collect_mtypes_cache
= new HashMap[MModule, Set[MClassType]]
1079 # A type based on a generic class.
1080 # A generic type a just a class with additional formal generic arguments.
1084 private init(mclass
: MClass, arguments
: Array[MType])
1087 assert self.mclass
.arity
== arguments
.length
1088 self.arguments
= arguments
1090 self.need_anchor
= false
1091 for t
in arguments
do
1092 if t
.need_anchor
then
1093 self.need_anchor
= true
1098 self.to_s
= "{mclass}[{arguments.join(", ")}]"
1101 # Recursively print the type of the arguments within brackets.
1102 # Example: `"Map[String, List[Int]]"`
1103 redef var to_s
: String
1105 redef var need_anchor
: Bool
1107 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1109 if not need_anchor
then return self
1110 assert can_resolve_for
(mtype
, anchor
, mmodule
)
1111 var types
= new Array[MType]
1112 for t
in arguments
do
1113 types
.add
(t
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
))
1115 return mclass
.get_mtype
(types
)
1118 redef fun can_resolve_for
(mtype
, anchor
, mmodule
)
1120 if not need_anchor
then return true
1121 for t
in arguments
do
1122 if not t
.can_resolve_for
(mtype
, anchor
, mmodule
) then return false
1131 for a
in self.arguments
do
1133 if d
> dmax
then dmax
= d
1141 for a
in self.arguments
do
1148 # A virtual formal type.
1152 # The property associated with the type.
1153 # Its the definitions of this property that determine the bound or the virtual type.
1154 var mproperty
: MProperty
1156 redef fun model
do return self.mproperty
.intro_mclassdef
.mmodule
.model
1158 # Lookup the bound for a given resolved_receiver
1159 # The result may be a other virtual type (or a parameter type)
1161 # The result is returned exactly as declared in the "type" property (verbatim).
1163 # In case of conflict, the method aborts.
1164 fun lookup_bound
(mmodule
: MModule, resolved_receiver
: MType): MType
1166 assert not resolved_receiver
.need_anchor
1167 var props
= self.mproperty
.lookup_definitions
(mmodule
, resolved_receiver
)
1168 if props
.is_empty
then
1170 else if props
.length
== 1 then
1171 return props
.first
.as(MVirtualTypeDef).bound
.as(not null)
1173 var types
= new ArraySet[MType]
1175 types
.add
(p
.as(MVirtualTypeDef).bound
.as(not null))
1177 if types
.length
== 1 then
1183 # Is the virtual type fixed for a given resolved_receiver?
1184 fun is_fixed
(mmodule
: MModule, resolved_receiver
: MType): Bool
1186 assert not resolved_receiver
.need_anchor
1187 var props
= self.mproperty
.lookup_definitions
(mmodule
, resolved_receiver
)
1188 if props
.is_empty
then
1192 if p
.as(MVirtualTypeDef).is_fixed
then return true
1197 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1199 assert can_resolve_for
(mtype
, anchor
, mmodule
)
1200 # self is a virtual type declared (or inherited) in mtype
1201 # The point of the function it to get the bound of the virtual type that make sense for mtype
1202 # But because mtype is maybe a virtual/formal type, we need to get a real receiver first
1203 #print "{class_name}: {self}/{mtype}/{anchor}?"
1204 var resolved_reciever
1205 if mtype
.need_anchor
then
1206 assert anchor
!= null
1207 resolved_reciever
= mtype
.resolve_for
(anchor
, null, mmodule
, true)
1209 resolved_reciever
= mtype
1211 # Now, we can get the bound
1212 var verbatim_bound
= lookup_bound
(mmodule
, resolved_reciever
)
1213 # The bound is exactly as declared in the "type" property, so we must resolve it again
1214 var res
= verbatim_bound
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1215 #print "{class_name}: {self}/{mtype}/{anchor} -> {self}/{resolved_receiver}/{anchor} -> {verbatim_bound}/{mtype}/{anchor} -> {res}"
1217 # What to return here? There is a bunch a special cases:
1218 # If 'cleanup_virtual' we must return the resolved type, since we cannot return self
1219 if cleanup_virtual
then return res
1220 # 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
1221 if resolved_reciever
isa MNullableType then resolved_reciever
= resolved_reciever
.mtype
1222 if resolved_reciever
.as(MClassType).mclass
.kind
== enum_kind
then return res
1223 # 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.
1224 if res
isa MVirtualType then return res
1225 # If we are final, just return the resolution
1226 if is_fixed
(mmodule
, resolved_reciever
) then return res
1227 # 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
1228 if res
isa MClassType and res
.mclass
.kind
== enum_kind
then return res
1229 # TODO: What if bound to a MParameterType?
1230 # Note that Nullable types can always be redefined by the non nullable version, so there is no specific case on it.
1232 # If anything apply, then `self' cannot be resolved, so return self
1236 redef fun can_resolve_for
(mtype
, anchor
, mmodule
)
1238 if mtype
.need_anchor
then
1239 assert anchor
!= null
1240 mtype
= mtype
.anchor_to
(mmodule
, anchor
)
1242 return mtype
.has_mproperty
(mmodule
, mproperty
)
1245 redef fun to_s
do return self.mproperty
.to_s
1247 init(mproperty
: MProperty)
1249 self.mproperty
= mproperty
1253 # The type associated to a formal parameter generic type of a class
1255 # Each parameter type is associated to a specific class.
1256 # It means that all refinements of a same class "share" the parameter type,
1257 # but that a generic subclass has its own parameter types.
1259 # However, in the sense of the meta-model, a parameter type of a class is
1260 # a valid type in a subclass. The "in the sense of the meta-model" is
1261 # important because, in the Nit language, the programmer cannot refers
1262 # directly to the parameter types of the super-classes.
1266 # fun e: E is abstract
1271 # In the class definition B[F], `F` is a valid type but `E` is not.
1272 # However, `self.e` is a valid method call, and the signature of `e` is
1275 # Note that parameter types are shared among class refinements.
1276 # Therefore parameter only have an internal name (see `to_s` for details).
1277 class MParameterType
1280 # The generic class where the parameter belong
1283 redef fun model
do return self.mclass
.intro_mmodule
.model
1285 # The position of the parameter (0 for the first parameter)
1286 # FIXME: is `position` a better name?
1291 redef fun to_s
do return name
1293 # Resolve the bound for a given resolved_receiver
1294 # The result may be a other virtual type (or a parameter type)
1295 fun lookup_bound
(mmodule
: MModule, resolved_receiver
: MType): MType
1297 assert not resolved_receiver
.need_anchor
1298 var goalclass
= self.mclass
1299 var supertypes
= resolved_receiver
.collect_mtypes
(mmodule
)
1300 for t
in supertypes
do
1301 if t
.mclass
== goalclass
then
1302 # Yeah! c specialize goalclass with a "super `t'". So the question is what is the argument of f
1303 # FIXME: Here, we stop on the first goal. Should we check others and detect inconsistencies?
1304 var res
= t
.arguments
[self.rank
]
1311 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1313 assert can_resolve_for
(mtype
, anchor
, mmodule
)
1314 #print "{class_name}: {self}/{mtype}/{anchor}?"
1316 if mtype
isa MGenericType and mtype
.mclass
== self.mclass
then
1317 var res
= mtype
.arguments
[self.rank
]
1318 if anchor
!= null and res
.need_anchor
then
1319 # Maybe the result can be resolved more if are bound to a final class
1320 var r2
= res
.anchor_to
(mmodule
, anchor
)
1321 if r2
isa MClassType and r2
.mclass
.kind
== enum_kind
then return r2
1326 # self is a parameter type of mtype (or of a super-class of mtype)
1327 # The point of the function it to get the bound of the virtual type that make sense for mtype
1328 # But because mtype is maybe a virtual/formal type, we need to get a real receiver first
1329 # FIXME: What happens here is far from clear. Thus this part must be validated and clarified
1330 var resolved_receiver
1331 if mtype
.need_anchor
then
1332 assert anchor
!= null
1333 resolved_receiver
= mtype
.resolve_for
(anchor
.mclass
.mclass_type
, anchor
, mmodule
, true)
1335 resolved_receiver
= mtype
1337 if resolved_receiver
isa MNullableType then resolved_receiver
= resolved_receiver
.mtype
1338 if resolved_receiver
isa MParameterType then
1339 assert resolved_receiver
.mclass
== anchor
.mclass
1340 resolved_receiver
= anchor
.arguments
[resolved_receiver
.rank
]
1341 if resolved_receiver
isa MNullableType then resolved_receiver
= resolved_receiver
.mtype
1343 assert resolved_receiver
isa MClassType
1345 # Eh! The parameter is in the current class.
1346 # So we return the corresponding argument, no mater what!
1347 if resolved_receiver
.mclass
== self.mclass
then
1348 var res
= resolved_receiver
.arguments
[self.rank
]
1349 #print "{class_name}: {self}/{mtype}/{anchor} -> direct {res}"
1353 if resolved_receiver
.need_anchor
then
1354 assert anchor
!= null
1355 resolved_receiver
= resolved_receiver
.resolve_for
(anchor
, null, mmodule
, false)
1357 # Now, we can get the bound
1358 var verbatim_bound
= lookup_bound
(mmodule
, resolved_receiver
)
1359 # The bound is exactly as declared in the "type" property, so we must resolve it again
1360 var res
= verbatim_bound
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1362 #print "{class_name}: {self}/{mtype}/{anchor} -> indirect {res}"
1367 redef fun can_resolve_for
(mtype
, anchor
, mmodule
)
1369 if mtype
.need_anchor
then
1370 assert anchor
!= null
1371 mtype
= mtype
.anchor_to
(mmodule
, anchor
)
1373 return mtype
.collect_mclassdefs
(mmodule
).has
(mclass
.intro
)
1376 init(mclass
: MClass, rank
: Int, name
: String)
1378 self.mclass
= mclass
1384 # A type prefixed with "nullable"
1388 # The base type of the nullable type
1391 redef fun model
do return self.mtype
.model
1396 self.to_s
= "nullable {mtype}"
1399 redef var to_s
: String
1401 redef fun need_anchor
do return mtype
.need_anchor
1402 redef fun as_nullable
do return self
1403 redef fun as_notnullable
do return mtype
1404 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1406 var res
= self.mtype
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1407 return res
.as_nullable
1410 redef fun can_resolve_for
(mtype
, anchor
, mmodule
)
1412 return self.mtype
.can_resolve_for
(mtype
, anchor
, mmodule
)
1415 redef fun depth
do return self.mtype
.depth
1417 redef fun length
do return self.mtype
.length
1419 redef fun collect_mclassdefs
(mmodule
)
1421 assert not self.need_anchor
1422 return self.mtype
.collect_mclassdefs
(mmodule
)
1425 redef fun collect_mclasses
(mmodule
)
1427 assert not self.need_anchor
1428 return self.mtype
.collect_mclasses
(mmodule
)
1431 redef fun collect_mtypes
(mmodule
)
1433 assert not self.need_anchor
1434 return self.mtype
.collect_mtypes
(mmodule
)
1438 # The type of the only value null
1440 # The is only one null type per model, see `MModel::null_type`.
1443 redef var model
: Model
1444 protected init(model
: Model)
1448 redef fun to_s
do return "null"
1449 redef fun as_nullable
do return self
1450 redef fun need_anchor
do return false
1451 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
) do return self
1452 redef fun can_resolve_for
(mtype
, anchor
, mmodule
) do return true
1454 redef fun collect_mclassdefs
(mmodule
) do return new HashSet[MClassDef]
1456 redef fun collect_mclasses
(mmodule
) do return new HashSet[MClass]
1458 redef fun collect_mtypes
(mmodule
) do return new HashSet[MClassType]
1461 # A signature of a method
1465 # The each parameter (in order)
1466 var mparameters
: Array[MParameter]
1468 # The return type (null for a procedure)
1469 var return_mtype
: nullable MType
1474 var t
= self.return_mtype
1475 if t
!= null then dmax
= t
.depth
1476 for p
in mparameters
do
1477 var d
= p
.mtype
.depth
1478 if d
> dmax
then dmax
= d
1486 var t
= self.return_mtype
1487 if t
!= null then res
+= t
.length
1488 for p
in mparameters
do
1489 res
+= p
.mtype
.length
1494 # REQUIRE: 1 <= mparameters.count p -> p.is_vararg
1495 init(mparameters
: Array[MParameter], return_mtype
: nullable MType)
1497 var vararg_rank
= -1
1498 for i
in [0..mparameters
.length
[ do
1499 var parameter
= mparameters
[i
]
1500 if parameter
.is_vararg
then
1501 assert vararg_rank
== -1
1505 self.mparameters
= mparameters
1506 self.return_mtype
= return_mtype
1507 self.vararg_rank
= vararg_rank
1510 # The rank of the ellipsis (`...`) for vararg (starting from 0).
1511 # value is -1 if there is no vararg.
1512 # Example: for "(a: Int, b: Bool..., c: Char)" #-> vararg_rank=1
1513 var vararg_rank
: Int
1515 # The number or parameters
1516 fun arity
: Int do return mparameters
.length
1520 var b
= new FlatBuffer
1521 if not mparameters
.is_empty
then
1523 for i
in [0..mparameters
.length
[ do
1524 var mparameter
= mparameters
[i
]
1525 if i
> 0 then b
.append
(", ")
1526 b
.append
(mparameter
.name
)
1528 b
.append
(mparameter
.mtype
.to_s
)
1529 if mparameter
.is_vararg
then
1535 var ret
= self.return_mtype
1543 redef fun resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule, cleanup_virtual
: Bool): MSignature
1545 var params
= new Array[MParameter]
1546 for p
in self.mparameters
do
1547 params
.add
(p
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
))
1549 var ret
= self.return_mtype
1551 ret
= ret
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1553 var res
= new MSignature(params
, ret
)
1558 # A parameter in a signature
1562 # The name of the parameter
1563 redef var name
: String
1565 # The static type of the parameter
1568 # Is the parameter a vararg?
1571 init(name
: String, mtype
: MType, is_vararg
: Bool) do
1574 self.is_vararg
= is_vararg
1580 return "{name}: {mtype}..."
1582 return "{name}: {mtype}"
1586 fun resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule, cleanup_virtual
: Bool): MParameter
1588 if not self.mtype
.need_anchor
then return self
1589 var newtype
= self.mtype
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1590 var res
= new MParameter(self.name
, newtype
, self.is_vararg
)
1594 redef fun model
do return mtype
.model
1597 # A service (global property) that generalize method, attribute, etc.
1599 # `MProperty` are global to the model; it means that a `MProperty` is not bound
1600 # to a specific `MModule` nor a specific `MClass`.
1602 # A MProperty gather definitions (see `mpropdefs`) ; one for the introduction
1603 # and the other in subclasses and in refinements.
1605 # A `MProperty` is used to denotes services in polymorphic way (ie. independent
1606 # of any dynamic type).
1607 # For instance, a call site "x.foo" is associated to a `MProperty`.
1608 abstract class MProperty
1611 # The associated MPropDef subclass.
1612 # The two specialization hierarchy are symmetric.
1613 type MPROPDEF: MPropDef
1615 # The classdef that introduce the property
1616 # While a property is not bound to a specific module, or class,
1617 # the introducing mclassdef is used for naming and visibility
1618 var intro_mclassdef
: MClassDef
1620 # The (short) name of the property
1621 redef var name
: String
1623 # The canonical name of the property
1624 # Example: "owner::my_module::MyClass::my_method"
1625 fun full_name
: String
1627 return "{self.intro_mclassdef.mmodule.full_name}::{self.intro_mclassdef.mclass.name}::{name}"
1630 # The visibility of the property
1631 var visibility
: MVisibility
1633 init(intro_mclassdef
: MClassDef, name
: String, visibility
: MVisibility)
1635 self.intro_mclassdef
= intro_mclassdef
1637 self.visibility
= visibility
1638 intro_mclassdef
.intro_mproperties
.add
(self)
1639 var model
= intro_mclassdef
.mmodule
.model
1640 model
.mproperties_by_name
.add_one
(name
, self)
1641 model
.mproperties
.add
(self)
1644 # All definitions of the property.
1645 # The first is the introduction,
1646 # The other are redefinitions (in refinements and in subclasses)
1647 var mpropdefs
= new Array[MPROPDEF]
1649 # The definition that introduced the property
1650 # Warning: the introduction is the first `MPropDef` object
1651 # associated to self. If self is just created without having any
1652 # associated definition, this method will abort
1653 fun intro
: MPROPDEF do return mpropdefs
.first
1655 redef fun model
do return intro
.model
1658 redef fun to_s
do return name
1660 # Return the most specific property definitions defined or inherited by a type.
1661 # The selection knows that refinement is stronger than specialization;
1662 # however, in case of conflict more than one property are returned.
1663 # If mtype does not know mproperty then an empty array is returned.
1665 # If you want the really most specific property, then look at `lookup_first_definition`
1666 fun lookup_definitions
(mmodule
: MModule, mtype
: MType): Array[MPROPDEF]
1668 assert not mtype
.need_anchor
1669 mtype
= mtype
.as_notnullable
1671 var cache
= self.lookup_definitions_cache
[mmodule
, mtype
]
1672 if cache
!= null then return cache
1674 #print "select prop {mproperty} for {mtype} in {self}"
1675 # First, select all candidates
1676 var candidates
= new Array[MPROPDEF]
1677 for mpropdef
in self.mpropdefs
do
1678 # If the definition is not imported by the module, then skip
1679 if not mmodule
.in_importation
<= mpropdef
.mclassdef
.mmodule
then continue
1680 # If the definition is not inherited by the type, then skip
1681 if not mtype
.is_subtype
(mmodule
, null, mpropdef
.mclassdef
.bound_mtype
) then continue
1683 candidates
.add
(mpropdef
)
1685 # Fast track for only one candidate
1686 if candidates
.length
<= 1 then
1687 self.lookup_definitions_cache
[mmodule
, mtype
] = candidates
1691 # Second, filter the most specific ones
1692 return select_most_specific
(mmodule
, candidates
)
1695 private var lookup_definitions_cache
= new HashMap2[MModule, MType, Array[MPROPDEF]]
1697 # Return the most specific property definitions inherited by a type.
1698 # The selection knows that refinement is stronger than specialization;
1699 # however, in case of conflict more than one property are returned.
1700 # If mtype does not know mproperty then an empty array is returned.
1702 # If you want the really most specific property, then look at `lookup_next_definition`
1704 # FIXME: Move to `MPropDef`?
1705 fun lookup_super_definitions
(mmodule
: MModule, mtype
: MType): Array[MPROPDEF]
1707 assert not mtype
.need_anchor
1708 mtype
= mtype
.as_notnullable
1710 # First, select all candidates
1711 var candidates
= new Array[MPROPDEF]
1712 for mpropdef
in self.mpropdefs
do
1713 # If the definition is not imported by the module, then skip
1714 if not mmodule
.in_importation
<= mpropdef
.mclassdef
.mmodule
then continue
1715 # If the definition is not inherited by the type, then skip
1716 if not mtype
.is_subtype
(mmodule
, null, mpropdef
.mclassdef
.bound_mtype
) then continue
1717 # If the definition is defined by the type, then skip (we want the super, so e skip the current)
1718 if mtype
== mpropdef
.mclassdef
.bound_mtype
and mmodule
== mpropdef
.mclassdef
.mmodule
then continue
1720 candidates
.add
(mpropdef
)
1722 # Fast track for only one candidate
1723 if candidates
.length
<= 1 then return candidates
1725 # Second, filter the most specific ones
1726 return select_most_specific
(mmodule
, candidates
)
1729 # Return an array containing olny the most specific property definitions
1730 # This is an helper function for `lookup_definitions` and `lookup_super_definitions`
1731 private fun select_most_specific
(mmodule
: MModule, candidates
: Array[MPROPDEF]): Array[MPROPDEF]
1733 var res
= new Array[MPROPDEF]
1734 for pd1
in candidates
do
1735 var cd1
= pd1
.mclassdef
1738 for pd2
in candidates
do
1739 if pd2
== pd1
then continue # do not compare with self!
1740 var cd2
= pd2
.mclassdef
1742 if c2
.mclass_type
== c1
.mclass_type
then
1743 if cd2
.mmodule
.in_importation
< cd1
.mmodule
then
1744 # cd2 refines cd1; therefore we skip pd1
1748 else if cd2
.bound_mtype
.is_subtype
(mmodule
, null, cd1
.bound_mtype
) and cd2
.bound_mtype
!= cd1
.bound_mtype
then
1749 # cd2 < cd1; therefore we skip pd1
1758 if res
.is_empty
then
1759 print
"All lost! {candidates.join(", ")}"
1760 # FIXME: should be abort!
1765 # Return the most specific definition in the linearization of `mtype`.
1767 # If you want to know the next properties in the linearization,
1768 # look at `MPropDef::lookup_next_definition`.
1770 # FIXME: the linearization is still unspecified
1772 # REQUIRE: `not mtype.need_anchor`
1773 # REQUIRE: `mtype.has_mproperty(mmodule, self)`
1774 fun lookup_first_definition
(mmodule
: MModule, mtype
: MType): MPROPDEF
1776 assert mtype
.has_mproperty
(mmodule
, self)
1777 return lookup_all_definitions
(mmodule
, mtype
).first
1780 # Return all definitions in a linearization order
1781 # Most specific first, most general last
1782 fun lookup_all_definitions
(mmodule
: MModule, mtype
: MType): Array[MPROPDEF]
1784 assert not mtype
.need_anchor
1785 mtype
= mtype
.as_notnullable
1787 var cache
= self.lookup_all_definitions_cache
[mmodule
, mtype
]
1788 if cache
!= null then return cache
1790 #print "select prop {mproperty} for {mtype} in {self}"
1791 # First, select all candidates
1792 var candidates
= new Array[MPROPDEF]
1793 for mpropdef
in self.mpropdefs
do
1794 # If the definition is not imported by the module, then skip
1795 if not mmodule
.in_importation
<= mpropdef
.mclassdef
.mmodule
then continue
1796 # If the definition is not inherited by the type, then skip
1797 if not mtype
.is_subtype
(mmodule
, null, mpropdef
.mclassdef
.bound_mtype
) then continue
1799 candidates
.add
(mpropdef
)
1801 # Fast track for only one candidate
1802 if candidates
.length
<= 1 then
1803 self.lookup_all_definitions_cache
[mmodule
, mtype
] = candidates
1807 mmodule
.linearize_mpropdefs
(candidates
)
1808 candidates
= candidates
.reversed
1809 self.lookup_all_definitions_cache
[mmodule
, mtype
] = candidates
1813 private var lookup_all_definitions_cache
= new HashMap2[MModule, MType, Array[MPROPDEF]]
1820 redef type MPROPDEF: MMethodDef
1822 init(intro_mclassdef
: MClassDef, name
: String, visibility
: MVisibility)
1827 # Is the property defined at the top_level of the module?
1828 # Currently such a property are stored in `Object`
1829 var is_toplevel
: Bool = false is writable
1831 # Is the property a constructor?
1832 # Warning, this property can be inherited by subclasses with or without being a constructor
1833 # therefore, you should use `is_init_for` the verify if the property is a legal constructor for a given class
1834 var is_init
: Bool = false is writable
1836 # The constructor is a (the) root init with empty signature but a set of initializers
1837 var is_root_init
: Bool = false is writable
1839 # Is the property a 'new' constructor?
1840 var is_new
: Bool = false is writable
1842 # Is the property a legal constructor for a given class?
1843 # As usual, visibility is not considered.
1844 # FIXME not implemented
1845 fun is_init_for
(mclass
: MClass): Bool
1851 # A global attribute
1855 redef type MPROPDEF: MAttributeDef
1857 init(intro_mclassdef
: MClassDef, name
: String, visibility
: MVisibility)
1863 # A global virtual type
1864 class MVirtualTypeProp
1867 redef type MPROPDEF: MVirtualTypeDef
1869 init(intro_mclassdef
: MClassDef, name
: String, visibility
: MVisibility)
1874 # The formal type associated to the virtual type property
1875 var mvirtualtype
= new MVirtualType(self)
1878 # A definition of a property (local property)
1880 # Unlike `MProperty`, a `MPropDef` is a local definition that belong to a
1881 # specific class definition (which belong to a specific module)
1882 abstract class MPropDef
1885 # The associated `MProperty` subclass.
1886 # the two specialization hierarchy are symmetric
1887 type MPROPERTY: MProperty
1890 type MPROPDEF: MPropDef
1892 # The origin of the definition
1893 var location
: Location
1895 # The class definition where the property definition is
1896 var mclassdef
: MClassDef
1898 # The associated global property
1899 var mproperty
: MPROPERTY
1901 init(mclassdef
: MClassDef, mproperty
: MPROPERTY, location
: Location)
1903 self.mclassdef
= mclassdef
1904 self.mproperty
= mproperty
1905 self.location
= location
1906 mclassdef
.mpropdefs
.add
(self)
1907 mproperty
.mpropdefs
.add
(self)
1908 self.to_s
= "{mclassdef}#{mproperty}"
1911 # Actually the name of the `mproperty`
1912 redef fun name
do return mproperty
.name
1914 redef fun model
do return mclassdef
.model
1916 # Internal name combining the module, the class and the property
1917 # Example: "mymodule#MyClass#mymethod"
1918 redef var to_s
: String
1920 # Is self the definition that introduce the property?
1921 fun is_intro
: Bool do return mproperty
.intro
== self
1923 # Return the next definition in linearization of `mtype`.
1925 # This method is used to determine what method is called by a super.
1927 # REQUIRE: `not mtype.need_anchor`
1928 fun lookup_next_definition
(mmodule
: MModule, mtype
: MType): MPROPDEF
1930 assert not mtype
.need_anchor
1932 var mpropdefs
= self.mproperty
.lookup_all_definitions
(mmodule
, mtype
)
1933 var i
= mpropdefs
.iterator
1934 while i
.is_ok
and i
.item
!= self do i
.next
1935 assert has_property
: i
.is_ok
1937 assert has_next_property
: i
.is_ok
1942 # A local definition of a method
1946 redef type MPROPERTY: MMethod
1947 redef type MPROPDEF: MMethodDef
1949 init(mclassdef
: MClassDef, mproperty
: MPROPERTY, location
: Location)
1954 # The signature attached to the property definition
1955 var msignature
: nullable MSignature = null is writable
1957 # The signature attached to the `new` call on a root-init
1958 # This is a concatenation of the signatures of the initializers
1960 # REQUIRE `mproperty.is_root_init == (new_msignature != null)`
1961 var new_msignature
: nullable MSignature = null is writable
1963 # List of initialisers to call in root-inits
1965 # They could be setters or attributes
1967 # REQUIRE `mproperty.is_root_init == (new_msignature != null)`
1968 var initializers
= new Array[MProperty]
1970 # Is the method definition abstract?
1971 var is_abstract
: Bool = false is writable
1973 # Is the method definition intern?
1974 var is_intern
= false is writable
1976 # Is the method definition extern?
1977 var is_extern
= false is writable
1979 # An optional constant value returned in functions.
1981 # Only some specific primitife value are accepted by engines.
1982 # Is used when there is no better implementation available.
1984 # Currently used only for the implementation of the `--define`
1985 # command-line option.
1986 # SEE: module `mixin`.
1987 var constant_value
: nullable Object = null is writable
1990 # A local definition of an attribute
1994 redef type MPROPERTY: MAttribute
1995 redef type MPROPDEF: MAttributeDef
1997 init(mclassdef
: MClassDef, mproperty
: MPROPERTY, location
: Location)
2002 # The static type of the attribute
2003 var static_mtype
: nullable MType = null is writable
2006 # A local definition of a virtual type
2007 class MVirtualTypeDef
2010 redef type MPROPERTY: MVirtualTypeProp
2011 redef type MPROPDEF: MVirtualTypeDef
2013 init(mclassdef
: MClassDef, mproperty
: MPROPERTY, location
: Location)
2018 # The bound of the virtual type
2019 var bound
: nullable MType = null is writable
2021 # Is the bound fixed?
2022 var is_fixed
= false is writable
2029 # * `interface_kind`
2033 # Note this class is basically an enum.
2034 # FIXME: use a real enum once user-defined enums are available
2036 redef var to_s
: String
2038 # Is a constructor required?
2040 private init(s
: String, need_init
: Bool)
2043 self.need_init
= need_init
2046 # Can a class of kind `self` specializes a class of kine `other`?
2047 fun can_specialize
(other
: MClassKind): Bool
2049 if other
== interface_kind
then return true # everybody can specialize interfaces
2050 if self == interface_kind
or self == enum_kind
then
2051 # no other case for interfaces
2053 else if self == extern_kind
then
2054 # only compatible with themselves
2055 return self == other
2056 else if other
== enum_kind
or other
== extern_kind
then
2057 # abstract_kind and concrete_kind are incompatible
2060 # remain only abstract_kind and concrete_kind
2065 # The class kind `abstract`
2066 fun abstract_kind
: MClassKind do return once
new MClassKind("abstract class", true)
2067 # The class kind `concrete`
2068 fun concrete_kind
: MClassKind do return once
new MClassKind("class", true)
2069 # The class kind `interface`
2070 fun interface_kind
: MClassKind do return once
new MClassKind("interface", false)
2071 # The class kind `enum`
2072 fun enum_kind
: MClassKind do return once
new MClassKind("enum", false)
2073 # The class kind `extern`
2074 fun extern_kind
: MClassKind do return once
new MClassKind("extern class", false)