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
, 0, enum_kind
, public_visibility
)
254 var cladef
= new MClassDef(self, c
.mclass_type
, new Location(null, 0,0,0,0), new Array[String])
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 # The kind of the class (interface, abstract class, etc.)
364 # In Nit, the kind of a class cannot evolve in refinements
367 # The visibility of the class
368 # In Nit, the visibility of a class cannot evolve in refinements
369 var visibility
: MVisibility
371 init(intro_mmodule
: MModule, name
: String, arity
: Int, kind
: MClassKind, visibility
: MVisibility)
373 self.intro_mmodule
= intro_mmodule
377 self.visibility
= visibility
378 intro_mmodule
.intro_mclasses
.add
(self)
379 var model
= intro_mmodule
.model
380 model
.mclasses_by_name
.add_one
(name
, self)
381 model
.mclasses
.add
(self)
383 # Create the formal parameter types
385 var mparametertypes
= new Array[MParameterType]
386 for i
in [0..arity
[ do
387 var mparametertype
= new MParameterType(self, i
)
388 mparametertypes
.add
(mparametertype
)
390 var mclass_type
= new MGenericType(self, mparametertypes
)
391 self.mclass_type
= mclass_type
392 self.get_mtype_cache
.add
(mclass_type
)
394 self.mclass_type
= new MClassType(self)
398 redef fun model
do return intro_mmodule
.model
400 # All class definitions (introduction and refinements)
401 var mclassdefs
: Array[MClassDef] = new Array[MClassDef]
404 redef fun to_s
do return self.name
406 # The definition that introduced the class
407 # Warning: the introduction is the first `MClassDef` object associated
408 # to self. If self is just created without having any associated
409 # definition, this method will abort
412 assert has_a_first_definition
: not mclassdefs
.is_empty
413 return mclassdefs
.first
416 # Return the class `self` in the class hierarchy of the module `mmodule`.
418 # SEE: `MModule::flatten_mclass_hierarchy`
419 # REQUIRE: `mmodule.has_mclass(self)`
420 fun in_hierarchy
(mmodule
: MModule): POSetElement[MClass]
422 return mmodule
.flatten_mclass_hierarchy
[self]
425 # The principal static type of the class.
427 # For non-generic class, mclass_type is the only `MClassType` based
430 # For a generic class, the arguments are the formal parameters.
431 # i.e.: for the class Array[E:Object], the `mclass_type` is Array[E].
432 # If you want Array[Object] the see `MClassDef::bound_mtype`
434 # For generic classes, the mclass_type is also the way to get a formal
435 # generic parameter type.
437 # To get other types based on a generic class, see `get_mtype`.
439 # ENSURE: `mclass_type.mclass == self`
440 var mclass_type
: MClassType
442 # Return a generic type based on the class
443 # Is the class is not generic, then the result is `mclass_type`
445 # REQUIRE: `mtype_arguments.length == self.arity`
446 fun get_mtype
(mtype_arguments
: Array[MType]): MClassType
448 assert mtype_arguments
.length
== self.arity
449 if self.arity
== 0 then return self.mclass_type
450 for t
in self.get_mtype_cache
do
451 if t
.arguments
== mtype_arguments
then
455 var res
= new MGenericType(self, mtype_arguments
)
456 self.get_mtype_cache
.add res
460 private var get_mtype_cache
: Array[MGenericType] = new Array[MGenericType]
464 # A definition (an introduction or a refinement) of a class in a module
466 # A `MClassDef` is associated with an explicit (or almost) definition of a
467 # class. Unlike `MClass`, a `MClassDef` is a local definition that belong to
468 # a specific class and a specific module, and contains declarations like super-classes
471 # It is the class definitions that are the backbone of most things in the model:
472 # ClassDefs are defined with regard with other classdefs.
473 # Refinement and specialization are combined to produce a big poset called the `Model::mclassdef_hierarchy`.
475 # Moreover, the extension and the intention of types is defined by looking at the MClassDefs.
479 # The module where the definition is
482 # The associated `MClass`
485 # The bounded type associated to the mclassdef
487 # For a non-generic class, `bound_mtype` and `mclass.mclass_type`
491 # For the classdef Array[E: Object], the bound_mtype is Array[Object].
492 # If you want Array[E], then see `mclass.mclass_type`
494 # ENSURE: `bound_mtype.mclass == self.mclass`
495 var bound_mtype
: MClassType
497 # Name of each formal generic parameter (in order of declaration)
498 var parameter_names
: Array[String]
500 # The origin of the definition
501 var location
: Location
503 # Internal name combining the module and the class
504 # Example: "mymodule#MyClass"
505 redef var to_s
: String
507 init(mmodule
: MModule, bound_mtype
: MClassType, location
: Location, parameter_names
: Array[String])
509 assert bound_mtype
.mclass
.arity
== parameter_names
.length
510 self.bound_mtype
= bound_mtype
511 self.mmodule
= mmodule
512 self.mclass
= bound_mtype
.mclass
513 self.location
= location
514 mmodule
.mclassdefs
.add
(self)
515 mclass
.mclassdefs
.add
(self)
516 self.parameter_names
= parameter_names
517 self.to_s
= "{mmodule}#{mclass}"
520 # Actually the name of the `mclass`
521 redef fun name
do return mclass
.name
523 redef fun model
do return mmodule
.model
525 # All declared super-types
526 # FIXME: quite ugly but not better idea yet
527 var supertypes
: Array[MClassType] = new Array[MClassType]
529 # Register some super-types for the class (ie "super SomeType")
531 # The hierarchy must not already be set
532 # REQUIRE: `self.in_hierarchy == null`
533 fun set_supertypes
(supertypes
: Array[MClassType])
535 assert unique_invocation
: self.in_hierarchy
== null
536 var mmodule
= self.mmodule
537 var model
= mmodule
.model
538 var mtype
= self.bound_mtype
540 for supertype
in supertypes
do
541 self.supertypes
.add
(supertype
)
543 # Register in full_type_specialization_hierarchy
544 model
.full_mtype_specialization_hierarchy
.add_edge
(mtype
, supertype
)
545 # Register in intro_type_specialization_hierarchy
546 if mclass
.intro_mmodule
== mmodule
and supertype
.mclass
.intro_mmodule
== mmodule
then
547 model
.intro_mtype_specialization_hierarchy
.add_edge
(mtype
, supertype
)
553 # Collect the super-types (set by set_supertypes) to build the hierarchy
555 # This function can only invoked once by class
556 # REQUIRE: `self.in_hierarchy == null`
557 # ENSURE: `self.in_hierarchy != null`
560 assert unique_invocation
: self.in_hierarchy
== null
561 var model
= mmodule
.model
562 var res
= model
.mclassdef_hierarchy
.add_node
(self)
563 self.in_hierarchy
= res
564 var mtype
= self.bound_mtype
566 # Here we need to connect the mclassdef to its pairs in the mclassdef_hierarchy
567 # The simpliest way is to attach it to collect_mclassdefs
568 for mclassdef
in mtype
.collect_mclassdefs
(mmodule
) do
569 res
.poset
.add_edge
(self, mclassdef
)
573 # The view of the class definition in `mclassdef_hierarchy`
574 var in_hierarchy
: nullable POSetElement[MClassDef] = null
576 # Is the definition the one that introduced `mclass`?
577 fun is_intro
: Bool do return mclass
.intro
== self
579 # All properties introduced by the classdef
580 var intro_mproperties
: Array[MProperty] = new Array[MProperty]
582 # All property definitions in the class (introductions and redefinitions)
583 var mpropdefs
: Array[MPropDef] = new Array[MPropDef]
586 # A global static type
588 # MType are global to the model; it means that a `MType` is not bound to a
589 # specific `MModule`.
590 # This characteristic helps the reasoning about static types in a program
591 # since a single `MType` object always denote the same type.
593 # However, because a `MType` is global, it does not really have properties
594 # nor have subtypes to a hierarchy since the property and the class hierarchy
595 # depends of a module.
596 # Moreover, virtual types an formal generic parameter types also depends on
597 # a receiver to have sense.
599 # Therefore, most method of the types require a module and an anchor.
600 # The module is used to know what are the classes and the specialization
602 # The anchor is used to know what is the bound of the virtual types and formal
603 # generic parameter types.
605 # MType are not directly usable to get properties. See the `anchor_to` method
606 # and the `MClassType` class.
608 # FIXME: the order of the parameters is not the best. We mus pick on from:
609 # * foo(mmodule, anchor, othertype)
610 # * foo(othertype, anchor, mmodule)
611 # * foo(anchor, mmodule, othertype)
612 # * foo(othertype, mmodule, anchor)
616 redef fun name
do return to_s
618 # Return true if `self` is an subtype of `sup`.
619 # The typing is done using the standard typing policy of Nit.
621 # REQUIRE: `anchor == null implies not self.need_anchor and not sup.need_anchor`
622 # REQUIRE: `anchor != null implies self.can_resolve_for(anchor, null, mmodule) and sup.can_resolve_for(anchor, null, mmodule)`
623 fun is_subtype
(mmodule
: MModule, anchor
: nullable MClassType, sup
: MType): Bool
626 if sub
== sup
then return true
627 if anchor
== null then
628 assert not sub
.need_anchor
629 assert not sup
.need_anchor
631 assert sub
.can_resolve_for
(anchor
, null, mmodule
)
632 assert sup
.can_resolve_for
(anchor
, null, mmodule
)
635 # First, resolve the formal types to a common version in the receiver
636 # The trick here is that fixed formal type will be associed to the bound
637 # And unfixed formal types will be associed to a canonical formal type.
638 if sub
isa MParameterType or sub
isa MVirtualType then
639 assert anchor
!= null
640 sub
= sub
.resolve_for
(anchor
.mclass
.mclass_type
, anchor
, mmodule
, false)
642 if sup
isa MParameterType or sup
isa MVirtualType then
643 assert anchor
!= null
644 sup
= sup
.resolve_for
(anchor
.mclass
.mclass_type
, anchor
, mmodule
, false)
647 # Does `sup` accept null or not?
648 # Discard the nullable marker if it exists
649 var sup_accept_null
= false
650 if sup
isa MNullableType then
651 sup_accept_null
= true
653 else if sup
isa MNullType then
654 sup_accept_null
= true
657 # Can `sub` provide null or not?
658 # Thus we can match with `sup_accept_null`
659 # Also discard the nullable marker if it exists
660 if sub
isa MNullableType then
661 if not sup_accept_null
then return false
663 else if sub
isa MNullType then
664 return sup_accept_null
666 # Now the case of direct null and nullable is over.
668 # A unfixed formal type can only accept itself
669 if sup
isa MParameterType or sup
isa MVirtualType then
673 # If `sub` is a formal type, then it is accepted if its bound is accepted
674 if sub
isa MParameterType or sub
isa MVirtualType then
675 assert anchor
!= null
676 sub
= sub
.anchor_to
(mmodule
, anchor
)
678 # Manage the second layer of null/nullable
679 if sub
isa MNullableType then
680 if not sup_accept_null
then return false
682 else if sub
isa MNullType then
683 return sup_accept_null
687 assert sub
isa MClassType # It is the only remaining type
689 if sup
isa MNullType then
690 # `sup` accepts only null
694 assert sup
isa MClassType # It is the only remaining type
696 # Now both are MClassType, we need to dig
698 if sub
== sup
then return true
700 if anchor
== null then anchor
= sub
# UGLY: any anchor will work
701 var resolved_sub
= sub
.anchor_to
(mmodule
, anchor
)
702 var res
= resolved_sub
.collect_mclasses
(mmodule
).has
(sup
.mclass
)
703 if res
== false then return false
704 if not sup
isa MGenericType then return true
705 var sub2
= sub
.supertype_to
(mmodule
, anchor
, sup
.mclass
)
706 assert sub2
.mclass
== sup
.mclass
707 for i
in [0..sup
.mclass
.arity
[ do
708 var sub_arg
= sub2
.arguments
[i
]
709 var sup_arg
= sup
.arguments
[i
]
710 res
= sub_arg
.is_subtype
(mmodule
, anchor
, sup_arg
)
711 if res
== false then return false
716 # The base class type on which self is based
718 # This base type is used to get property (an internally to perform
719 # unsafe type comparison).
721 # Beware: some types (like null) are not based on a class thus this
724 # Basically, this function transform the virtual types and parameter
725 # types to their bounds.
729 # class B super A end
731 # class Y super X end
739 # Map[T,U] anchor_to H #-> Map[B,Y]
741 # Explanation of the example:
742 # In H, T is set to B, because "H super G[B]", and U is bound to Y,
743 # because "redef type U: Y". Therefore, Map[T, U] is bound to
746 # ENSURE: `not self.need_anchor implies result == self`
747 # ENSURE: `not result.need_anchor`
748 fun anchor_to
(mmodule
: MModule, anchor
: MClassType): MType
750 if not need_anchor
then return self
751 assert not anchor
.need_anchor
752 # Just resolve to the anchor and clear all the virtual types
753 var res
= self.resolve_for
(anchor
, null, mmodule
, true)
754 assert not res
.need_anchor
758 # Does `self` contain a virtual type or a formal generic parameter type?
759 # In order to remove those types, you usually want to use `anchor_to`.
760 fun need_anchor
: Bool do return true
762 # Return the supertype when adapted to a class.
764 # In Nit, for each super-class of a type, there is a equivalent super-type.
768 # class H[V] super G[V, Bool] end
769 # H[Int] supertype_to G #-> G[Int, Bool]
771 # REQUIRE: `super_mclass` is a super-class of `self`
772 # REQUIRE: `self.need_anchor implies anchor != null and self.can_resolve_for(anchor, null, mmodule)`
773 # ENSURE: `result.mclass = super_mclass`
774 fun supertype_to
(mmodule
: MModule, anchor
: nullable MClassType, super_mclass
: MClass): MClassType
776 if super_mclass
.arity
== 0 then return super_mclass
.mclass_type
777 if self isa MClassType and self.mclass
== super_mclass
then return self
779 if self.need_anchor
then
780 assert anchor
!= null
781 resolved_self
= self.anchor_to
(mmodule
, anchor
)
785 var supertypes
= resolved_self
.collect_mtypes
(mmodule
)
786 for supertype
in supertypes
do
787 if supertype
.mclass
== super_mclass
then
788 # FIXME: Here, we stop on the first goal. Should we check others and detect inconsistencies?
789 return supertype
.resolve_for
(self, anchor
, mmodule
, false)
795 # Replace formals generic types in self with resolved values in `mtype`
796 # If `cleanup_virtual` is true, then virtual types are also replaced
799 # This function returns self if `need_anchor` is false.
804 # class H[F] super G[F] end
807 # * Array[E].resolve_for(H[Int]) #-> Array[Int]
808 # * Array[E].resolve_for(G[Z], X[Int]) #-> Array[Z]
810 # Explanation of the example:
811 # * Array[E].need_anchor is true because there is a formal generic parameter type E
812 # * E makes sense for H[Int] because E is a formal parameter of G and H specialize G
813 # * Since "H[F] super G[F]", E is in fact F for H
814 # * More specifically, in H[Int], E is Int
815 # * So, in H[Int], Array[E] is Array[Int]
817 # This function is mainly used to inherit a signature.
818 # Because, unlike `anchor_to`, we do not want a full resolution of
819 # a type but only an adapted version of it.
824 # fun foo(e:E):E is abstract
826 # class B super A[Int] end
828 # The signature on foo is (e: E): E
829 # If we resolve the signature for B, we get (e:Int):Int
834 # fun foo(e:E) is abstract
838 # fun bar do a.foo(x) # <- x is here
841 # The first question is: is foo available on `a`?
843 # The static type of a is `A[Array[F]]`, that is an open type.
844 # in order to find a method `foo`, whe must look at a resolved type.
846 # A[Array[F]].anchor_to(B[nullable Object]) #-> A[Array[nullable Object]]
848 # the method `foo` exists in `A[Array[nullable Object]]`, therefore `foo` exists for `a`.
850 # The next question is: what is the accepted types for `x`?
852 # the signature of `foo` is `foo(e:E)`, thus we must resolve the type E
854 # E.resolve_for(A[Array[F]],B[nullable Object]) #-> Array[F]
856 # The resolution can be done because `E` make sense for the class A (see `can_resolve_for`)
858 # FIXME: the parameter `cleanup_virtual` is just a bad idea, but having
859 # two function instead of one seems also to be a bad idea.
861 # REQUIRE: `can_resolve_for(mtype, anchor, mmodule)`
862 # ENSURE: `not self.need_anchor implies result == self`
863 fun resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule, cleanup_virtual
: Bool): MType is abstract
865 # Can the type be resolved?
867 # In order to resolve open types, the formal types must make sence.
876 # * E.can_resolve_for(A[Int]) #-> true, E make sense in A
877 # * E.can_resolve_for(B[Int]) #-> false, E does not make sense in B
878 # * B[E].can_resolve_for(A[F], B[Object]) #-> true,
879 # B[E] is a red hearing only the E is important,
882 # REQUIRE: `anchor != null implies not anchor.need_anchor`
883 # REQUIRE: `mtype.need_anchor implies anchor != null and mtype.can_resolve_for(anchor, null, mmodule)`
884 # ENSURE: `not self.need_anchor implies result == true`
885 fun can_resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule): Bool is abstract
887 # Return the nullable version of the type
888 # If the type is already nullable then self is returned
889 fun as_nullable
: MType
891 var res
= self.as_nullable_cache
892 if res
!= null then return res
893 res
= new MNullableType(self)
894 self.as_nullable_cache
= res
898 # Return the not nullable version of the type
899 # Is the type is already not nullable, then self is returned.
901 # Note: this just remove the `nullable` notation, but the result can still contains null.
902 # For instance if `self isa MNullType` or self is a a formal type bounded by a nullable type.
903 fun as_notnullable
: MType
908 private var as_nullable_cache
: nullable MType = null
911 # The deph of the type seen as a tree.
918 # Formal types have a depth of 1.
924 # The length of the type seen as a tree.
931 # Formal types have a length of 1.
937 # Compute all the classdefs inherited/imported.
938 # The returned set contains:
939 # * the class definitions from `mmodule` and its imported modules
940 # * the class definitions of this type and its super-types
942 # This function is used mainly internally.
944 # REQUIRE: `not self.need_anchor`
945 fun collect_mclassdefs
(mmodule
: MModule): Set[MClassDef] is abstract
947 # Compute all the super-classes.
948 # This function is used mainly internally.
950 # REQUIRE: `not self.need_anchor`
951 fun collect_mclasses
(mmodule
: MModule): Set[MClass] is abstract
953 # Compute all the declared super-types.
954 # Super-types are returned as declared in the classdefs (verbatim).
955 # This function is used mainly internally.
957 # REQUIRE: `not self.need_anchor`
958 fun collect_mtypes
(mmodule
: MModule): Set[MClassType] is abstract
960 # Is the property in self for a given module
961 # This method does not filter visibility or whatever
963 # REQUIRE: `not self.need_anchor`
964 fun has_mproperty
(mmodule
: MModule, mproperty
: MProperty): Bool
966 assert not self.need_anchor
967 return self.collect_mclassdefs
(mmodule
).has
(mproperty
.intro_mclassdef
)
971 # A type based on a class.
973 # `MClassType` have properties (see `has_mproperty`).
977 # The associated class
980 redef fun model
do return self.mclass
.intro_mmodule
.model
982 private init(mclass
: MClass)
987 # The formal arguments of the type
988 # ENSURE: `result.length == self.mclass.arity`
989 var arguments
: Array[MType] = new Array[MType]
991 redef fun to_s
do return mclass
.to_s
993 redef fun need_anchor
do return false
995 redef fun anchor_to
(mmodule
: MModule, anchor
: MClassType): MClassType
997 return super.as(MClassType)
1000 redef fun resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule, cleanup_virtual
: Bool): MClassType do return self
1002 redef fun can_resolve_for
(mtype
, anchor
, mmodule
) do return true
1004 redef fun collect_mclassdefs
(mmodule
)
1006 assert not self.need_anchor
1007 var cache
= self.collect_mclassdefs_cache
1008 if not cache
.has_key
(mmodule
) then
1009 self.collect_things
(mmodule
)
1011 return cache
[mmodule
]
1014 redef fun collect_mclasses
(mmodule
)
1016 assert not self.need_anchor
1017 var cache
= self.collect_mclasses_cache
1018 if not cache
.has_key
(mmodule
) then
1019 self.collect_things
(mmodule
)
1021 return cache
[mmodule
]
1024 redef fun collect_mtypes
(mmodule
)
1026 assert not self.need_anchor
1027 var cache
= self.collect_mtypes_cache
1028 if not cache
.has_key
(mmodule
) then
1029 self.collect_things
(mmodule
)
1031 return cache
[mmodule
]
1034 # common implementation for `collect_mclassdefs`, `collect_mclasses`, and `collect_mtypes`.
1035 private fun collect_things
(mmodule
: MModule)
1037 var res
= new HashSet[MClassDef]
1038 var seen
= new HashSet[MClass]
1039 var types
= new HashSet[MClassType]
1040 seen
.add
(self.mclass
)
1041 var todo
= [self.mclass
]
1042 while not todo
.is_empty
do
1043 var mclass
= todo
.pop
1044 #print "process {mclass}"
1045 for mclassdef
in mclass
.mclassdefs
do
1046 if not mmodule
.in_importation
<= mclassdef
.mmodule
then continue
1047 #print " process {mclassdef}"
1049 for supertype
in mclassdef
.supertypes
do
1050 types
.add
(supertype
)
1051 var superclass
= supertype
.mclass
1052 if seen
.has
(superclass
) then continue
1053 #print " add {superclass}"
1054 seen
.add
(superclass
)
1055 todo
.add
(superclass
)
1059 collect_mclassdefs_cache
[mmodule
] = res
1060 collect_mclasses_cache
[mmodule
] = seen
1061 collect_mtypes_cache
[mmodule
] = types
1064 private var collect_mclassdefs_cache
: HashMap[MModule, Set[MClassDef]] = new HashMap[MModule, Set[MClassDef]]
1065 private var collect_mclasses_cache
: HashMap[MModule, Set[MClass]] = new HashMap[MModule, Set[MClass]]
1066 private var collect_mtypes_cache
: HashMap[MModule, Set[MClassType]] = new HashMap[MModule, Set[MClassType]]
1070 # A type based on a generic class.
1071 # A generic type a just a class with additional formal generic arguments.
1075 private init(mclass
: MClass, arguments
: Array[MType])
1078 assert self.mclass
.arity
== arguments
.length
1079 self.arguments
= arguments
1081 self.need_anchor
= false
1082 for t
in arguments
do
1083 if t
.need_anchor
then
1084 self.need_anchor
= true
1089 self.to_s
= "{mclass}[{arguments.join(", ")}]"
1092 # Recursively print the type of the arguments within brackets.
1093 # Example: `"Map[String, List[Int]]"`
1094 redef var to_s
: String
1096 redef var need_anchor
: Bool
1098 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1100 if not need_anchor
then return self
1101 assert can_resolve_for
(mtype
, anchor
, mmodule
)
1102 var types
= new Array[MType]
1103 for t
in arguments
do
1104 types
.add
(t
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
))
1106 return mclass
.get_mtype
(types
)
1109 redef fun can_resolve_for
(mtype
, anchor
, mmodule
)
1111 if not need_anchor
then return true
1112 for t
in arguments
do
1113 if not t
.can_resolve_for
(mtype
, anchor
, mmodule
) then return false
1122 for a
in self.arguments
do
1124 if d
> dmax
then dmax
= d
1132 for a
in self.arguments
do
1139 # A virtual formal type.
1143 # The property associated with the type.
1144 # Its the definitions of this property that determine the bound or the virtual type.
1145 var mproperty
: MProperty
1147 redef fun model
do return self.mproperty
.intro_mclassdef
.mmodule
.model
1149 # Lookup the bound for a given resolved_receiver
1150 # The result may be a other virtual type (or a parameter type)
1152 # The result is returned exactly as declared in the "type" property (verbatim).
1154 # In case of conflict, the method aborts.
1155 fun lookup_bound
(mmodule
: MModule, resolved_receiver
: MType): MType
1157 assert not resolved_receiver
.need_anchor
1158 var props
= self.mproperty
.lookup_definitions
(mmodule
, resolved_receiver
)
1159 if props
.is_empty
then
1161 else if props
.length
== 1 then
1162 return props
.first
.as(MVirtualTypeDef).bound
.as(not null)
1164 var types
= new ArraySet[MType]
1166 types
.add
(p
.as(MVirtualTypeDef).bound
.as(not null))
1168 if types
.length
== 1 then
1174 # Is the virtual type fixed for a given resolved_receiver?
1175 fun is_fixed
(mmodule
: MModule, resolved_receiver
: MType): Bool
1177 assert not resolved_receiver
.need_anchor
1178 var props
= self.mproperty
.lookup_definitions
(mmodule
, resolved_receiver
)
1179 if props
.is_empty
then
1183 if p
.as(MVirtualTypeDef).is_fixed
then return true
1188 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1190 assert can_resolve_for
(mtype
, anchor
, mmodule
)
1191 # self is a virtual type declared (or inherited) in mtype
1192 # The point of the function it to get the bound of the virtual type that make sense for mtype
1193 # But because mtype is maybe a virtual/formal type, we need to get a real receiver first
1194 #print "{class_name}: {self}/{mtype}/{anchor}?"
1195 var resolved_reciever
1196 if mtype
.need_anchor
then
1197 assert anchor
!= null
1198 resolved_reciever
= mtype
.resolve_for
(anchor
, null, mmodule
, true)
1200 resolved_reciever
= mtype
1202 # Now, we can get the bound
1203 var verbatim_bound
= lookup_bound
(mmodule
, resolved_reciever
)
1204 # The bound is exactly as declared in the "type" property, so we must resolve it again
1205 var res
= verbatim_bound
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1206 #print "{class_name}: {self}/{mtype}/{anchor} -> {self}/{resolved_reciever}/{anchor} -> {verbatim_bound}/{mtype}/{anchor} -> {res}"
1208 # What to return here? There is a bunch a special cases:
1209 # If 'cleanup_virtual' we must return the resolved type, since we cannot return self
1210 if cleanup_virtual
then return res
1211 # 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
1212 if resolved_reciever
isa MNullableType then resolved_reciever
= resolved_reciever
.mtype
1213 if resolved_reciever
.as(MClassType).mclass
.kind
== enum_kind
then return res
1214 # 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.
1215 if res
isa MVirtualType then return res
1216 # If we are final, just return the resolution
1217 if is_fixed
(mmodule
, resolved_reciever
) then return res
1218 # 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
1219 if res
isa MClassType and res
.mclass
.kind
== enum_kind
then return res
1220 # TODO: Add 'fixed' virtual type in the specification.
1221 # TODO: What if bound to a MParameterType?
1222 # Note that Nullable types can always be redefined by the non nullable version, so there is no specific case on it.
1224 # If anything apply, then `self' cannot be resolved, so return self
1228 redef fun can_resolve_for
(mtype
, anchor
, mmodule
)
1230 if mtype
.need_anchor
then
1231 assert anchor
!= null
1232 mtype
= mtype
.anchor_to
(mmodule
, anchor
)
1234 return mtype
.has_mproperty
(mmodule
, mproperty
)
1237 redef fun to_s
do return self.mproperty
.to_s
1239 init(mproperty
: MProperty)
1241 self.mproperty
= mproperty
1245 # The type associated the a formal parameter generic type of a class
1247 # Each parameter type is associated to a specific class.
1248 # It means that all refinements of a same class "share" the parameter type,
1249 # but that a generic subclass has its own parameter types.
1251 # However, in the sense of the meta-model, a parameter type of a class is
1252 # a valid type in a subclass. The "in the sense of the meta-model" is
1253 # important because, in the Nit language, the programmer cannot refers
1254 # directly to the parameter types of the super-classes.
1258 # fun e: E is abstract
1263 # In the class definition B[F], `F` is a valid type but `E` is not.
1264 # However, `self.e` is a valid method call, and the signature of `e` is
1267 # Note that parameter types are shared among class refinements.
1268 # Therefore parameter only have an internal name (see `to_s` for details).
1269 # TODO: Add a `name_for` to get better messages.
1270 class MParameterType
1273 # The generic class where the parameter belong
1276 redef fun model
do return self.mclass
.intro_mmodule
.model
1278 # The position of the parameter (0 for the first parameter)
1279 # FIXME: is `position` a better name?
1282 # Internal name of the parameter type
1283 # Names of parameter types changes in each class definition
1284 # Therefore, this method return an internal name.
1285 # Example: return "G#1" for the second parameter of the class G
1286 # FIXME: add a way to get the real name in a classdef
1287 redef fun to_s
do return "{mclass}#{rank}"
1289 # Resolve the bound for a given resolved_receiver
1290 # The result may be a other virtual type (or a parameter type)
1291 fun lookup_bound
(mmodule
: MModule, resolved_receiver
: MType): MType
1293 assert not resolved_receiver
.need_anchor
1294 var goalclass
= self.mclass
1295 var supertypes
= resolved_receiver
.collect_mtypes
(mmodule
)
1296 for t
in supertypes
do
1297 if t
.mclass
== goalclass
then
1298 # Yeah! c specialize goalclass with a "super `t'". So the question is what is the argument of f
1299 # FIXME: Here, we stop on the first goal. Should we check others and detect inconsistencies?
1300 var res
= t
.arguments
[self.rank
]
1307 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1309 assert can_resolve_for
(mtype
, anchor
, mmodule
)
1310 #print "{class_name}: {self}/{mtype}/{anchor}?"
1312 if mtype
isa MGenericType and mtype
.mclass
== self.mclass
then
1313 var res
= mtype
.arguments
[self.rank
]
1314 if anchor
!= null and res
.need_anchor
then
1315 # Maybe the result can be resolved more if are bound to a final class
1316 var r2
= res
.anchor_to
(mmodule
, anchor
)
1317 if r2
isa MClassType and r2
.mclass
.kind
== enum_kind
then return r2
1322 # self is a parameter type of mtype (or of a super-class of mtype)
1323 # The point of the function it to get the bound of the virtual type that make sense for mtype
1324 # But because mtype is maybe a virtual/formal type, we need to get a real receiver first
1325 # FIXME: What happend here is far from clear. Thus this part must be validated and clarified
1326 var resolved_receiver
1327 if mtype
.need_anchor
then
1328 assert anchor
!= null
1329 resolved_receiver
= mtype
.resolve_for
(anchor
.mclass
.mclass_type
, anchor
, mmodule
, true)
1331 resolved_receiver
= mtype
1333 if resolved_receiver
isa MNullableType then resolved_receiver
= resolved_receiver
.mtype
1334 if resolved_receiver
isa MParameterType then
1335 assert resolved_receiver
.mclass
== anchor
.mclass
1336 resolved_receiver
= anchor
.arguments
[resolved_receiver
.rank
]
1337 if resolved_receiver
isa MNullableType then resolved_receiver
= resolved_receiver
.mtype
1339 assert resolved_receiver
isa MClassType
1341 # Eh! The parameter is in the current class.
1342 # So we return the corresponding argument, no mater what!
1343 if resolved_receiver
.mclass
== self.mclass
then
1344 var res
= resolved_receiver
.arguments
[self.rank
]
1345 #print "{class_name}: {self}/{mtype}/{anchor} -> direct {res}"
1349 if resolved_receiver
.need_anchor
then
1350 assert anchor
!= null
1351 resolved_receiver
= resolved_receiver
.resolve_for
(anchor
, null, mmodule
, false)
1353 # Now, we can get the bound
1354 var verbatim_bound
= lookup_bound
(mmodule
, resolved_receiver
)
1355 # The bound is exactly as declared in the "type" property, so we must resolve it again
1356 var res
= verbatim_bound
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1358 #print "{class_name}: {self}/{mtype}/{anchor} -> indirect {res}"
1363 redef fun can_resolve_for
(mtype
, anchor
, mmodule
)
1365 if mtype
.need_anchor
then
1366 assert anchor
!= null
1367 mtype
= mtype
.anchor_to
(mmodule
, anchor
)
1369 return mtype
.collect_mclassdefs
(mmodule
).has
(mclass
.intro
)
1372 init(mclass
: MClass, rank
: Int)
1374 self.mclass
= mclass
1379 # A type prefixed with "nullable"
1383 # The base type of the nullable type
1386 redef fun model
do return self.mtype
.model
1391 self.to_s
= "nullable {mtype}"
1394 redef var to_s
: String
1396 redef fun need_anchor
do return mtype
.need_anchor
1397 redef fun as_nullable
do return self
1398 redef fun as_notnullable
do return mtype
1399 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1401 var res
= self.mtype
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1402 return res
.as_nullable
1405 redef fun can_resolve_for
(mtype
, anchor
, mmodule
)
1407 return self.mtype
.can_resolve_for
(mtype
, anchor
, mmodule
)
1410 redef fun depth
do return self.mtype
.depth
1412 redef fun length
do return self.mtype
.length
1414 redef fun collect_mclassdefs
(mmodule
)
1416 assert not self.need_anchor
1417 return self.mtype
.collect_mclassdefs
(mmodule
)
1420 redef fun collect_mclasses
(mmodule
)
1422 assert not self.need_anchor
1423 return self.mtype
.collect_mclasses
(mmodule
)
1426 redef fun collect_mtypes
(mmodule
)
1428 assert not self.need_anchor
1429 return self.mtype
.collect_mtypes
(mmodule
)
1433 # The type of the only value null
1435 # The is only one null type per model, see `MModel::null_type`.
1438 redef var model
: Model
1439 protected init(model
: Model)
1443 redef fun to_s
do return "null"
1444 redef fun as_nullable
do return self
1445 redef fun need_anchor
do return false
1446 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
) do return self
1447 redef fun can_resolve_for
(mtype
, anchor
, mmodule
) do return true
1449 redef fun collect_mclassdefs
(mmodule
) do return new HashSet[MClassDef]
1451 redef fun collect_mclasses
(mmodule
) do return new HashSet[MClass]
1453 redef fun collect_mtypes
(mmodule
) do return new HashSet[MClassType]
1456 # A signature of a method
1460 # The each parameter (in order)
1461 var mparameters
: Array[MParameter]
1463 # The return type (null for a procedure)
1464 var return_mtype
: nullable MType
1469 var t
= self.return_mtype
1470 if t
!= null then dmax
= t
.depth
1471 for p
in mparameters
do
1472 var d
= p
.mtype
.depth
1473 if d
> dmax
then dmax
= d
1481 var t
= self.return_mtype
1482 if t
!= null then res
+= t
.length
1483 for p
in mparameters
do
1484 res
+= p
.mtype
.length
1489 # REQUIRE: 1 <= mparameters.count p -> p.is_vararg
1490 init(mparameters
: Array[MParameter], return_mtype
: nullable MType)
1492 var vararg_rank
= -1
1493 for i
in [0..mparameters
.length
[ do
1494 var parameter
= mparameters
[i
]
1495 if parameter
.is_vararg
then
1496 assert vararg_rank
== -1
1500 self.mparameters
= mparameters
1501 self.return_mtype
= return_mtype
1502 self.vararg_rank
= vararg_rank
1505 # The rank of the ellipsis (`...`) for vararg (starting from 0).
1506 # value is -1 if there is no vararg.
1507 # Example: for "(a: Int, b: Bool..., c: Char)" #-> vararg_rank=1
1508 var vararg_rank
: Int
1510 # The number or parameters
1511 fun arity
: Int do return mparameters
.length
1515 var b
= new FlatBuffer
1516 if not mparameters
.is_empty
then
1518 for i
in [0..mparameters
.length
[ do
1519 var mparameter
= mparameters
[i
]
1520 if i
> 0 then b
.append
(", ")
1521 b
.append
(mparameter
.name
)
1523 b
.append
(mparameter
.mtype
.to_s
)
1524 if mparameter
.is_vararg
then
1530 var ret
= self.return_mtype
1538 redef fun resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule, cleanup_virtual
: Bool): MSignature
1540 var params
= new Array[MParameter]
1541 for p
in self.mparameters
do
1542 params
.add
(p
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
))
1544 var ret
= self.return_mtype
1546 ret
= ret
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1548 var res
= new MSignature(params
, ret
)
1553 # A parameter in a signature
1557 # The name of the parameter
1558 redef var name
: String
1560 # The static type of the parameter
1563 # Is the parameter a vararg?
1566 init(name
: String, mtype
: MType, is_vararg
: Bool) do
1569 self.is_vararg
= is_vararg
1575 return "{name}: {mtype}..."
1577 return "{name}: {mtype}"
1581 fun resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule, cleanup_virtual
: Bool): MParameter
1583 if not self.mtype
.need_anchor
then return self
1584 var newtype
= self.mtype
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1585 var res
= new MParameter(self.name
, newtype
, self.is_vararg
)
1589 redef fun model
do return mtype
.model
1592 # A service (global property) that generalize method, attribute, etc.
1594 # `MProperty` are global to the model; it means that a `MProperty` is not bound
1595 # to a specific `MModule` nor a specific `MClass`.
1597 # A MProperty gather definitions (see `mpropdefs`) ; one for the introduction
1598 # and the other in subclasses and in refinements.
1600 # A `MProperty` is used to denotes services in polymorphic way (ie. independent
1601 # of any dynamic type).
1602 # For instance, a call site "x.foo" is associated to a `MProperty`.
1603 abstract class MProperty
1606 # The associated MPropDef subclass.
1607 # The two specialization hierarchy are symmetric.
1608 type MPROPDEF: MPropDef
1610 # The classdef that introduce the property
1611 # While a property is not bound to a specific module, or class,
1612 # the introducing mclassdef is used for naming and visibility
1613 var intro_mclassdef
: MClassDef
1615 # The (short) name of the property
1616 redef var name
: String
1618 # The canonical name of the property
1619 # Example: "owner::my_module::MyClass::my_method"
1620 fun full_name
: String
1622 return "{self.intro_mclassdef.mmodule.full_name}::{self.intro_mclassdef.mclass.name}::{name}"
1625 # The visibility of the property
1626 var visibility
: MVisibility
1628 init(intro_mclassdef
: MClassDef, name
: String, visibility
: MVisibility)
1630 self.intro_mclassdef
= intro_mclassdef
1632 self.visibility
= visibility
1633 intro_mclassdef
.intro_mproperties
.add
(self)
1634 var model
= intro_mclassdef
.mmodule
.model
1635 model
.mproperties_by_name
.add_one
(name
, self)
1636 model
.mproperties
.add
(self)
1639 # All definitions of the property.
1640 # The first is the introduction,
1641 # The other are redefinitions (in refinements and in subclasses)
1642 var mpropdefs
: Array[MPROPDEF] = new Array[MPROPDEF]
1644 # The definition that introduced the property
1645 # Warning: the introduction is the first `MPropDef` object
1646 # associated to self. If self is just created without having any
1647 # associated definition, this method will abort
1648 fun intro
: MPROPDEF do return mpropdefs
.first
1650 redef fun model
do return intro
.model
1653 redef fun to_s
do return name
1655 # Return the most specific property definitions defined or inherited by a type.
1656 # The selection knows that refinement is stronger than specialization;
1657 # however, in case of conflict more than one property are returned.
1658 # If mtype does not know mproperty then an empty array is returned.
1660 # If you want the really most specific property, then look at `lookup_first_definition`
1661 fun lookup_definitions
(mmodule
: MModule, mtype
: MType): Array[MPROPDEF]
1663 assert not mtype
.need_anchor
1664 mtype
= mtype
.as_notnullable
1666 var cache
= self.lookup_definitions_cache
[mmodule
, mtype
]
1667 if cache
!= null then return cache
1669 #print "select prop {mproperty} for {mtype} in {self}"
1670 # First, select all candidates
1671 var candidates
= new Array[MPROPDEF]
1672 for mpropdef
in self.mpropdefs
do
1673 # If the definition is not imported by the module, then skip
1674 if not mmodule
.in_importation
<= mpropdef
.mclassdef
.mmodule
then continue
1675 # If the definition is not inherited by the type, then skip
1676 if not mtype
.is_subtype
(mmodule
, null, mpropdef
.mclassdef
.bound_mtype
) then continue
1678 candidates
.add
(mpropdef
)
1680 # Fast track for only one candidate
1681 if candidates
.length
<= 1 then
1682 self.lookup_definitions_cache
[mmodule
, mtype
] = candidates
1686 # Second, filter the most specific ones
1687 return select_most_specific
(mmodule
, candidates
)
1690 private var lookup_definitions_cache
: HashMap2[MModule, MType, Array[MPROPDEF]] = new HashMap2[MModule, MType, Array[MPROPDEF]]
1692 # Return the most specific property definitions inherited by a type.
1693 # The selection knows that refinement is stronger than specialization;
1694 # however, in case of conflict more than one property are returned.
1695 # If mtype does not know mproperty then an empty array is returned.
1697 # If you want the really most specific property, then look at `lookup_next_definition`
1699 # FIXME: Move to `MPropDef`?
1700 fun lookup_super_definitions
(mmodule
: MModule, mtype
: MType): Array[MPROPDEF]
1702 assert not mtype
.need_anchor
1703 mtype
= mtype
.as_notnullable
1705 # First, select all candidates
1706 var candidates
= new Array[MPROPDEF]
1707 for mpropdef
in self.mpropdefs
do
1708 # If the definition is not imported by the module, then skip
1709 if not mmodule
.in_importation
<= mpropdef
.mclassdef
.mmodule
then continue
1710 # If the definition is not inherited by the type, then skip
1711 if not mtype
.is_subtype
(mmodule
, null, mpropdef
.mclassdef
.bound_mtype
) then continue
1712 # If the definition is defined by the type, then skip (we want the super, so e skip the current)
1713 if mtype
== mpropdef
.mclassdef
.bound_mtype
and mmodule
== mpropdef
.mclassdef
.mmodule
then continue
1715 candidates
.add
(mpropdef
)
1717 # Fast track for only one candidate
1718 if candidates
.length
<= 1 then return candidates
1720 # Second, filter the most specific ones
1721 return select_most_specific
(mmodule
, candidates
)
1724 # Return an array containing olny the most specific property definitions
1725 # This is an helper function for `lookup_definitions` and `lookup_super_definitions`
1726 private fun select_most_specific
(mmodule
: MModule, candidates
: Array[MPROPDEF]): Array[MPROPDEF]
1728 var res
= new Array[MPROPDEF]
1729 for pd1
in candidates
do
1730 var cd1
= pd1
.mclassdef
1733 for pd2
in candidates
do
1734 if pd2
== pd1
then continue # do not compare with self!
1735 var cd2
= pd2
.mclassdef
1737 if c2
.mclass_type
== c1
.mclass_type
then
1738 if cd2
.mmodule
.in_importation
< cd1
.mmodule
then
1739 # cd2 refines cd1; therefore we skip pd1
1743 else if cd2
.bound_mtype
.is_subtype
(mmodule
, null, cd1
.bound_mtype
) and cd2
.bound_mtype
!= cd1
.bound_mtype
then
1744 # cd2 < cd1; therefore we skip pd1
1753 if res
.is_empty
then
1754 print
"All lost! {candidates.join(", ")}"
1755 # FIXME: should be abort!
1760 # Return the most specific definition in the linearization of `mtype`.
1762 # If you want to know the next properties in the linearization,
1763 # look at `MPropDef::lookup_next_definition`.
1765 # FIXME: the linearisation is still unspecified
1767 # REQUIRE: `not mtype.need_anchor`
1768 # REQUIRE: `mtype.has_mproperty(mmodule, self)`
1769 fun lookup_first_definition
(mmodule
: MModule, mtype
: MType): MPROPDEF
1771 assert mtype
.has_mproperty
(mmodule
, self)
1772 return lookup_all_definitions
(mmodule
, mtype
).first
1775 # Return all definitions in a linearisation order
1776 # Most speficic first, most general last
1777 fun lookup_all_definitions
(mmodule
: MModule, mtype
: MType): Array[MPROPDEF]
1779 assert not mtype
.need_anchor
1780 mtype
= mtype
.as_notnullable
1782 var cache
= self.lookup_all_definitions_cache
[mmodule
, mtype
]
1783 if cache
!= null then return cache
1785 #print "select prop {mproperty} for {mtype} in {self}"
1786 # First, select all candidates
1787 var candidates
= new Array[MPROPDEF]
1788 for mpropdef
in self.mpropdefs
do
1789 # If the definition is not imported by the module, then skip
1790 if not mmodule
.in_importation
<= mpropdef
.mclassdef
.mmodule
then continue
1791 # If the definition is not inherited by the type, then skip
1792 if not mtype
.is_subtype
(mmodule
, null, mpropdef
.mclassdef
.bound_mtype
) then continue
1794 candidates
.add
(mpropdef
)
1796 # Fast track for only one candidate
1797 if candidates
.length
<= 1 then
1798 self.lookup_all_definitions_cache
[mmodule
, mtype
] = candidates
1802 mmodule
.linearize_mpropdefs
(candidates
)
1803 candidates
= candidates
.reversed
1804 self.lookup_all_definitions_cache
[mmodule
, mtype
] = candidates
1808 private var lookup_all_definitions_cache
: HashMap2[MModule, MType, Array[MPROPDEF]] = new HashMap2[MModule, MType, Array[MPROPDEF]]
1815 redef type MPROPDEF: MMethodDef
1817 init(intro_mclassdef
: MClassDef, name
: String, visibility
: MVisibility)
1822 # Is the property defined at the top_level of the module?
1823 # Currently such a property are stored in `Object`
1824 var is_toplevel
: Bool = false is writable
1826 # Is the property a constructor?
1827 # Warning, this property can be inherited by subclasses with or without being a constructor
1828 # therefore, you should use `is_init_for` the verify if the property is a legal constructor for a given class
1829 var is_init
: Bool = false is writable
1831 # The constructor is a (the) root init with empty signature but a set of initializers
1832 var is_root_init
: Bool = false is writable
1834 # The the property a 'new' contructor?
1835 var is_new
: Bool = false is writable
1837 # Is the property a legal constructor for a given class?
1838 # As usual, visibility is not considered.
1839 # FIXME not implemented
1840 fun is_init_for
(mclass
: MClass): Bool
1846 # A global attribute
1850 redef type MPROPDEF: MAttributeDef
1852 init(intro_mclassdef
: MClassDef, name
: String, visibility
: MVisibility)
1858 # A global virtual type
1859 class MVirtualTypeProp
1862 redef type MPROPDEF: MVirtualTypeDef
1864 init(intro_mclassdef
: MClassDef, name
: String, visibility
: MVisibility)
1869 # The formal type associated to the virtual type property
1870 var mvirtualtype
: MVirtualType = new MVirtualType(self)
1873 # A definition of a property (local property)
1875 # Unlike `MProperty`, a `MPropDef` is a local definition that belong to a
1876 # specific class definition (which belong to a specific module)
1877 abstract class MPropDef
1880 # The associated `MProperty` subclass.
1881 # the two specialization hierarchy are symmetric
1882 type MPROPERTY: MProperty
1885 type MPROPDEF: MPropDef
1887 # The origin of the definition
1888 var location
: Location
1890 # The class definition where the property definition is
1891 var mclassdef
: MClassDef
1893 # The associated global property
1894 var mproperty
: MPROPERTY
1896 init(mclassdef
: MClassDef, mproperty
: MPROPERTY, location
: Location)
1898 self.mclassdef
= mclassdef
1899 self.mproperty
= mproperty
1900 self.location
= location
1901 mclassdef
.mpropdefs
.add
(self)
1902 mproperty
.mpropdefs
.add
(self)
1903 self.to_s
= "{mclassdef}#{mproperty}"
1906 # Actually the name of the `mproperty`
1907 redef fun name
do return mproperty
.name
1909 redef fun model
do return mclassdef
.model
1911 # Internal name combining the module, the class and the property
1912 # Example: "mymodule#MyClass#mymethod"
1913 redef var to_s
: String
1915 # Is self the definition that introduce the property?
1916 fun is_intro
: Bool do return mproperty
.intro
== self
1918 # Return the next definition in linearization of `mtype`.
1920 # This method is used to determine what method is called by a super.
1922 # REQUIRE: `not mtype.need_anchor`
1923 fun lookup_next_definition
(mmodule
: MModule, mtype
: MType): MPROPDEF
1925 assert not mtype
.need_anchor
1927 var mpropdefs
= self.mproperty
.lookup_all_definitions
(mmodule
, mtype
)
1928 var i
= mpropdefs
.iterator
1929 while i
.is_ok
and i
.item
!= self do i
.next
1930 assert has_property
: i
.is_ok
1932 assert has_next_property
: i
.is_ok
1937 # A local definition of a method
1941 redef type MPROPERTY: MMethod
1942 redef type MPROPDEF: MMethodDef
1944 init(mclassdef
: MClassDef, mproperty
: MPROPERTY, location
: Location)
1949 # The signature attached to the property definition
1950 var msignature
: nullable MSignature = null is writable
1952 # The signature attached to the `new` call on a root-init
1953 # This is a concatenation of the signatures of the initializers
1955 # REQUIRE `mproperty.is_root_init == (new_msignature != null)`
1956 var new_msignature
: nullable MSignature = null is writable
1958 # List of initialisers to call in root-inits
1960 # They could be setters or attributes
1962 # REQUIRE `mproperty.is_root_init == (new_msignature != null)`
1963 var initializers
= new Array[MProperty]
1965 # Is the method definition abstract?
1966 var is_abstract
: Bool = false is writable
1968 # Is the method definition intern?
1969 var is_intern
= false is writable
1971 # Is the method definition extern?
1972 var is_extern
= false is writable
1975 # A local definition of an attribute
1979 redef type MPROPERTY: MAttribute
1980 redef type MPROPDEF: MAttributeDef
1982 init(mclassdef
: MClassDef, mproperty
: MPROPERTY, location
: Location)
1987 # The static type of the attribute
1988 var static_mtype
: nullable MType = null is writable
1991 # A local definition of a virtual type
1992 class MVirtualTypeDef
1995 redef type MPROPERTY: MVirtualTypeProp
1996 redef type MPROPDEF: MVirtualTypeDef
1998 init(mclassdef
: MClassDef, mproperty
: MPROPERTY, location
: Location)
2003 # The bound of the virtual type
2004 var bound
: nullable MType = null is writable
2006 # Is the bound fixed?
2007 var is_fixed
= false is writable
2014 # * `interface_kind`
2018 # Note this class is basically an enum.
2019 # FIXME: use a real enum once user-defined enums are available
2021 redef var to_s
: String
2023 # Is a constructor required?
2025 private init(s
: String, need_init
: Bool)
2028 self.need_init
= need_init
2031 # Can a class of kind `self` specializes a class of kine `other`?
2032 fun can_specialize
(other
: MClassKind): Bool
2034 if other
== interface_kind
then return true # everybody can specialize interfaces
2035 if self == interface_kind
or self == enum_kind
then
2036 # no other case for interfaces
2038 else if self == extern_kind
then
2039 # only compatible with themselve
2040 return self == other
2041 else if other
== enum_kind
or other
== extern_kind
then
2042 # abstract_kind and concrete_kind are incompatible
2045 # remain only abstract_kind and concrete_kind
2050 fun abstract_kind
: MClassKind do return once
new MClassKind("abstract class", true)
2051 fun concrete_kind
: MClassKind do return once
new MClassKind("class", true)
2052 fun interface_kind
: MClassKind do return once
new MClassKind("interface", false)
2053 fun enum_kind
: MClassKind do return once
new MClassKind("enum", false)
2054 fun extern_kind
: MClassKind do return once
new MClassKind("extern class", false)