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" and self.model
.get_mclasses_by_name
("Object") != null then
255 # Bool is injected because it is needed by engine to code the result
256 # of the implicit casts.
257 var c
= new MClass(self, name
, null, enum_kind
, public_visibility
)
258 var cladef
= new MClassDef(self, c
.mclass_type
, new Location(null, 0,0,0,0))
259 cladef
.set_supertypes
([object_type
])
260 cladef
.add_in_hierarchy
263 print
("Fatal Error: no primitive class {name}")
266 if cla
.length
!= 1 then
267 var msg
= "Fatal Error: more than one primitive class {name}:"
268 for c
in cla
do msg
+= " {c.full_name}"
275 # Try to get the primitive method named `name` on the type `recv`
276 fun try_get_primitive_method
(name
: String, recv
: MClass): nullable MMethod
278 var props
= self.model
.get_mproperties_by_name
(name
)
279 if props
== null then return null
280 var res
: nullable MMethod = null
281 for mprop
in props
do
282 assert mprop
isa MMethod
283 var intro
= mprop
.intro_mclassdef
284 for mclassdef
in recv
.mclassdefs
do
285 if not self.in_importation
.greaters
.has
(mclassdef
.mmodule
) then continue
286 if not mclassdef
.in_hierarchy
.greaters
.has
(intro
) then continue
289 else if res
!= mprop
then
290 print
("Fatal Error: ambigous property name '{name}'; conflict between {mprop.full_name} and {res.full_name}")
299 private class MClassDefSorter
301 redef type COMPARED: MClassDef
303 redef fun compare
(a
, b
)
307 if ca
!= cb
then return mmodule
.flatten_mclass_hierarchy
.compare
(ca
, cb
)
308 return mmodule
.model
.mclassdef_hierarchy
.compare
(a
, b
)
312 private class MPropDefSorter
314 redef type COMPARED: MPropDef
316 redef fun compare
(pa
, pb
)
322 if ca
!= cb
then return mmodule
.flatten_mclass_hierarchy
.compare
(ca
, cb
)
323 return mmodule
.model
.mclassdef_hierarchy
.compare
(a
, b
)
329 # `MClass` are global to the model; it means that a `MClass` is not bound to a
330 # specific `MModule`.
332 # This characteristic helps the reasoning about classes in a program since a
333 # single `MClass` object always denote the same class.
335 # The drawback is that classes (`MClass`) contain almost nothing by themselves.
336 # These do not really have properties nor belong to a hierarchy since the property and the
337 # hierarchy of a class depends of the refinement in the modules.
339 # Most services on classes require the precision of a module, and no one can asks what are
340 # the super-classes of a class nor what are properties of a class without precising what is
341 # the module considered.
343 # For instance, during the typing of a source-file, the module considered is the module of the file.
344 # eg. the question *is the method `foo` exists in the class `Bar`?* must be reformulated into
345 # *is the method `foo` exists in the class `Bar` in the current module?*
347 # During some global analysis, the module considered may be the main module of the program.
351 # The module that introduce the class
352 # While classes are not bound to a specific module,
353 # the introducing module is used for naming an visibility
354 var intro_mmodule
: MModule
356 # The short name of the class
357 # In Nit, the name of a class cannot evolve in refinements
358 redef var name
: String
360 # The canonical name of the class
362 # It is the name of the class prefixed by the full_name of the `intro_mmodule`
363 # Example: `"owner::module::MyClass"`
364 redef var full_name
is lazy
do return "{self.intro_mmodule.full_name}::{name}"
366 # The number of generic formal parameters
367 # 0 if the class is not generic
368 var arity
: Int is noinit
370 # Each generic formal parameters in order.
371 # is empty if the class is not generic
372 var mparameters
= new Array[MParameterType]
374 protected fun setup_parameter_names
(parameter_names
: nullable Array[String]) is
377 if parameter_names
== null then
380 self.arity
= parameter_names
.length
383 # Create the formal parameter types
385 assert parameter_names
!= null
386 var mparametertypes
= new Array[MParameterType]
387 for i
in [0..arity
[ do
388 var mparametertype
= new MParameterType(self, i
, parameter_names
[i
])
389 mparametertypes
.add
(mparametertype
)
391 self.mparameters
= mparametertypes
392 var mclass_type
= new MGenericType(self, mparametertypes
)
393 self.mclass_type
= mclass_type
394 self.get_mtype_cache
[mparametertypes
] = mclass_type
396 self.mclass_type
= new MClassType(self)
400 # The kind of the class (interface, abstract class, etc.)
401 # In Nit, the kind of a class cannot evolve in refinements
404 # The visibility of the class
405 # In Nit, the visibility of a class cannot evolve in refinements
406 var visibility
: MVisibility
410 intro_mmodule
.intro_mclasses
.add
(self)
411 var model
= intro_mmodule
.model
412 model
.mclasses_by_name
.add_one
(name
, self)
413 model
.mclasses
.add
(self)
416 redef fun model
do return intro_mmodule
.model
418 # All class definitions (introduction and refinements)
419 var mclassdefs
= new Array[MClassDef]
422 redef fun to_s
do return self.name
424 # The definition that introduces the class.
426 # Warning: such a definition may not exist in the early life of the object.
427 # In this case, the method will abort.
428 var intro
: MClassDef is noinit
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 is noinit
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 var res
= get_mtype_cache
.get_or_null
(mtype_arguments
)
465 if res
!= null then return res
466 res
= new MGenericType(self, mtype_arguments
)
467 self.get_mtype_cache
[mtype_arguments
.to_a
] = res
471 private var get_mtype_cache
= new HashMap[Array[MType], MGenericType]
475 # A definition (an introduction or a refinement) of a class in a module
477 # A `MClassDef` is associated with an explicit (or almost) definition of a
478 # class. Unlike `MClass`, a `MClassDef` is a local definition that belong to
479 # a specific class and a specific module, and contains declarations like super-classes
482 # It is the class definitions that are the backbone of most things in the model:
483 # ClassDefs are defined with regard with other classdefs.
484 # Refinement and specialization are combined to produce a big poset called the `Model::mclassdef_hierarchy`.
486 # Moreover, the extension and the intention of types is defined by looking at the MClassDefs.
490 # The module where the definition is
493 # The associated `MClass`
494 var mclass
: MClass is noinit
496 # The bounded type associated to the mclassdef
498 # For a non-generic class, `bound_mtype` and `mclass.mclass_type`
502 # For the classdef Array[E: Object], the bound_mtype is Array[Object].
503 # If you want Array[E], then see `mclass.mclass_type`
505 # ENSURE: `bound_mtype.mclass == self.mclass`
506 var bound_mtype
: MClassType
508 # The origin of the definition
509 var location
: Location
511 # Internal name combining the module and the class
512 # Example: "mymodule#MyClass"
513 redef var to_s
: String is noinit
517 self.mclass
= bound_mtype
.mclass
518 mmodule
.mclassdefs
.add
(self)
519 mclass
.mclassdefs
.add
(self)
520 if mclass
.intro_mmodule
== mmodule
then
521 assert not isset mclass
._intro
524 self.to_s
= "{mmodule}#{mclass}"
527 # Actually the name of the `mclass`
528 redef fun name
do return mclass
.name
530 # The module and class name separated by a '#'.
532 # The short-name of the class is used for introduction.
533 # Example: "my_module#MyClass"
535 # The full-name of the class is used for refinement.
536 # Example: "my_module#intro_module::MyClass"
537 redef var full_name
is lazy
do
539 return "{mmodule.full_name}#{mclass.name}"
541 return "{mmodule.full_name}#{mclass.full_name}"
545 redef fun model
do return mmodule
.model
547 # All declared super-types
548 # FIXME: quite ugly but not better idea yet
549 var supertypes
= new Array[MClassType]
551 # Register some super-types for the class (ie "super SomeType")
553 # The hierarchy must not already be set
554 # REQUIRE: `self.in_hierarchy == null`
555 fun set_supertypes
(supertypes
: Array[MClassType])
557 assert unique_invocation
: self.in_hierarchy
== null
558 var mmodule
= self.mmodule
559 var model
= mmodule
.model
560 var mtype
= self.bound_mtype
562 for supertype
in supertypes
do
563 self.supertypes
.add
(supertype
)
565 # Register in full_type_specialization_hierarchy
566 model
.full_mtype_specialization_hierarchy
.add_edge
(mtype
, supertype
)
567 # Register in intro_type_specialization_hierarchy
568 if mclass
.intro_mmodule
== mmodule
and supertype
.mclass
.intro_mmodule
== mmodule
then
569 model
.intro_mtype_specialization_hierarchy
.add_edge
(mtype
, supertype
)
575 # Collect the super-types (set by set_supertypes) to build the hierarchy
577 # This function can only invoked once by class
578 # REQUIRE: `self.in_hierarchy == null`
579 # ENSURE: `self.in_hierarchy != null`
582 assert unique_invocation
: self.in_hierarchy
== null
583 var model
= mmodule
.model
584 var res
= model
.mclassdef_hierarchy
.add_node
(self)
585 self.in_hierarchy
= res
586 var mtype
= self.bound_mtype
588 # Here we need to connect the mclassdef to its pairs in the mclassdef_hierarchy
589 # The simpliest way is to attach it to collect_mclassdefs
590 for mclassdef
in mtype
.collect_mclassdefs
(mmodule
) do
591 res
.poset
.add_edge
(self, mclassdef
)
595 # The view of the class definition in `mclassdef_hierarchy`
596 var in_hierarchy
: nullable POSetElement[MClassDef] = null
598 # Is the definition the one that introduced `mclass`?
599 fun is_intro
: Bool do return mclass
.intro
== self
601 # All properties introduced by the classdef
602 var intro_mproperties
= new Array[MProperty]
604 # All property definitions in the class (introductions and redefinitions)
605 var mpropdefs
= new Array[MPropDef]
608 # A global static type
610 # MType are global to the model; it means that a `MType` is not bound to a
611 # specific `MModule`.
612 # This characteristic helps the reasoning about static types in a program
613 # since a single `MType` object always denote the same type.
615 # However, because a `MType` is global, it does not really have properties
616 # nor have subtypes to a hierarchy since the property and the class hierarchy
617 # depends of a module.
618 # Moreover, virtual types an formal generic parameter types also depends on
619 # a receiver to have sense.
621 # Therefore, most method of the types require a module and an anchor.
622 # The module is used to know what are the classes and the specialization
624 # The anchor is used to know what is the bound of the virtual types and formal
625 # generic parameter types.
627 # MType are not directly usable to get properties. See the `anchor_to` method
628 # and the `MClassType` class.
630 # FIXME: the order of the parameters is not the best. We mus pick on from:
631 # * foo(mmodule, anchor, othertype)
632 # * foo(othertype, anchor, mmodule)
633 # * foo(anchor, mmodule, othertype)
634 # * foo(othertype, mmodule, anchor)
638 redef fun name
do return to_s
640 # Return true if `self` is an subtype of `sup`.
641 # The typing is done using the standard typing policy of Nit.
643 # REQUIRE: `anchor == null implies not self.need_anchor and not sup.need_anchor`
644 # REQUIRE: `anchor != null implies self.can_resolve_for(anchor, null, mmodule) and sup.can_resolve_for(anchor, null, mmodule)`
645 fun is_subtype
(mmodule
: MModule, anchor
: nullable MClassType, sup
: MType): Bool
648 if sub
== sup
then return true
650 #print "1.is {sub} a {sup}? ===="
652 if anchor
== null then
653 assert not sub
.need_anchor
654 assert not sup
.need_anchor
656 # First, resolve the formal types to the simplest equivalent forms in the receiver
657 assert sub
.can_resolve_for
(anchor
, null, mmodule
)
658 sub
= sub
.lookup_fixed
(mmodule
, anchor
)
659 assert sup
.can_resolve_for
(anchor
, null, mmodule
)
660 sup
= sup
.lookup_fixed
(mmodule
, anchor
)
663 # Does `sup` accept null or not?
664 # Discard the nullable marker if it exists
665 var sup_accept_null
= false
666 if sup
isa MNullableType then
667 sup_accept_null
= true
669 else if sup
isa MNullType then
670 sup_accept_null
= true
673 # Can `sub` provide null or not?
674 # Thus we can match with `sup_accept_null`
675 # Also discard the nullable marker if it exists
676 if sub
isa MNullableType then
677 if not sup_accept_null
then return false
679 else if sub
isa MNullType then
680 return sup_accept_null
682 # Now the case of direct null and nullable is over.
684 # If `sub` is a formal type, then it is accepted if its bound is accepted
685 while sub
isa MParameterType or sub
isa MVirtualType do
686 #print "3.is {sub} a {sup}?"
688 # A unfixed formal type can only accept itself
689 if sub
== sup
then return true
691 assert anchor
!= null
692 sub
= sub
.lookup_bound
(mmodule
, anchor
)
694 #print "3.is {sub} a {sup}?"
696 # Manage the second layer of null/nullable
697 if sub
isa MNullableType then
698 if not sup_accept_null
then return false
700 else if sub
isa MNullType then
701 return sup_accept_null
704 #print "4.is {sub} a {sup}? <- no more resolution"
706 assert sub
isa MClassType # It is the only remaining type
708 # A unfixed formal type can only accept itself
709 if sup
isa MParameterType or sup
isa MVirtualType then
713 if sup
isa MNullType then
714 # `sup` accepts only null
718 assert sup
isa MClassType # It is the only remaining type
720 # Now both are MClassType, we need to dig
722 if sub
== sup
then return true
724 if anchor
== null then anchor
= sub
# UGLY: any anchor will work
725 var resolved_sub
= sub
.anchor_to
(mmodule
, anchor
)
726 var res
= resolved_sub
.collect_mclasses
(mmodule
).has
(sup
.mclass
)
727 if res
== false then return false
728 if not sup
isa MGenericType then return true
729 var sub2
= sub
.supertype_to
(mmodule
, anchor
, sup
.mclass
)
730 assert sub2
.mclass
== sup
.mclass
731 for i
in [0..sup
.mclass
.arity
[ do
732 var sub_arg
= sub2
.arguments
[i
]
733 var sup_arg
= sup
.arguments
[i
]
734 res
= sub_arg
.is_subtype
(mmodule
, anchor
, sup_arg
)
735 if res
== false then return false
740 # The base class type on which self is based
742 # This base type is used to get property (an internally to perform
743 # unsafe type comparison).
745 # Beware: some types (like null) are not based on a class thus this
748 # Basically, this function transform the virtual types and parameter
749 # types to their bounds.
754 # class B super A end
756 # class Y super X end
765 # Map[T,U] anchor_to H #-> Map[B,Y]
767 # Explanation of the example:
768 # In H, T is set to B, because "H super G[B]", and U is bound to Y,
769 # because "redef type U: Y". Therefore, Map[T, U] is bound to
772 # ENSURE: `not self.need_anchor implies result == self`
773 # ENSURE: `not result.need_anchor`
774 fun anchor_to
(mmodule
: MModule, anchor
: MClassType): MType
776 if not need_anchor
then return self
777 assert not anchor
.need_anchor
778 # Just resolve to the anchor and clear all the virtual types
779 var res
= self.resolve_for
(anchor
, null, mmodule
, true)
780 assert not res
.need_anchor
784 # Does `self` contain a virtual type or a formal generic parameter type?
785 # In order to remove those types, you usually want to use `anchor_to`.
786 fun need_anchor
: Bool do return true
788 # Return the supertype when adapted to a class.
790 # In Nit, for each super-class of a type, there is a equivalent super-type.
796 # class H[V] super G[V, Bool] end
798 # H[Int] supertype_to G #-> G[Int, Bool]
801 # REQUIRE: `super_mclass` is a super-class of `self`
802 # REQUIRE: `self.need_anchor implies anchor != null and self.can_resolve_for(anchor, null, mmodule)`
803 # ENSURE: `result.mclass = super_mclass`
804 fun supertype_to
(mmodule
: MModule, anchor
: nullable MClassType, super_mclass
: MClass): MClassType
806 if super_mclass
.arity
== 0 then return super_mclass
.mclass_type
807 if self isa MClassType and self.mclass
== super_mclass
then return self
809 if self.need_anchor
then
810 assert anchor
!= null
811 resolved_self
= self.anchor_to
(mmodule
, anchor
)
815 var supertypes
= resolved_self
.collect_mtypes
(mmodule
)
816 for supertype
in supertypes
do
817 if supertype
.mclass
== super_mclass
then
818 # FIXME: Here, we stop on the first goal. Should we check others and detect inconsistencies?
819 return supertype
.resolve_for
(self, anchor
, mmodule
, false)
825 # Replace formals generic types in self with resolved values in `mtype`
826 # If `cleanup_virtual` is true, then virtual types are also replaced
829 # This function returns self if `need_anchor` is false.
835 # class H[F] super G[F] end
839 # * Array[E].resolve_for(H[Int]) #-> Array[Int]
840 # * Array[E].resolve_for(G[Z], X[Int]) #-> Array[Z]
842 # Explanation of the example:
843 # * Array[E].need_anchor is true because there is a formal generic parameter type E
844 # * E makes sense for H[Int] because E is a formal parameter of G and H specialize G
845 # * Since "H[F] super G[F]", E is in fact F for H
846 # * More specifically, in H[Int], E is Int
847 # * So, in H[Int], Array[E] is Array[Int]
849 # This function is mainly used to inherit a signature.
850 # Because, unlike `anchor_to`, we do not want a full resolution of
851 # a type but only an adapted version of it.
857 # fun foo(e:E):E is abstract
859 # class B super A[Int] end
862 # The signature on foo is (e: E): E
863 # If we resolve the signature for B, we get (e:Int):Int
869 # fun foo(e:E):E is abstract
873 # fun bar do a.foo(x) # <- x is here
877 # The first question is: is foo available on `a`?
879 # The static type of a is `A[Array[F]]`, that is an open type.
880 # in order to find a method `foo`, whe must look at a resolved type.
882 # A[Array[F]].anchor_to(C[nullable Object]) #-> A[Array[nullable Object]]
884 # the method `foo` exists in `A[Array[nullable Object]]`, therefore `foo` exists for `a`.
886 # The next question is: what is the accepted types for `x`?
888 # the signature of `foo` is `foo(e:E)`, thus we must resolve the type E
890 # E.resolve_for(A[Array[F]],C[nullable Object]) #-> Array[F]
892 # The resolution can be done because `E` make sense for the class A (see `can_resolve_for`)
894 # FIXME: the parameter `cleanup_virtual` is just a bad idea, but having
895 # two function instead of one seems also to be a bad idea.
897 # REQUIRE: `can_resolve_for(mtype, anchor, mmodule)`
898 # ENSURE: `not self.need_anchor implies result == self`
899 fun resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule, cleanup_virtual
: Bool): MType is abstract
901 # Resolve formal type to its verbatim bound.
902 # If the type is not formal, just return self
904 # The result is returned exactly as declared in the "type" property (verbatim).
905 # So it could be another formal type.
907 # In case of conflict, the method aborts.
908 fun lookup_bound
(mmodule
: MModule, resolved_receiver
: MType): MType do return self
910 # Resolve the formal type to its simplest equivalent form.
912 # Formal types are either free or fixed.
913 # When it is fixed, it means that it is equivalent with a simpler type.
914 # When a formal type is free, it means that it is only equivalent with itself.
915 # This method return the most simple equivalent type of `self`.
917 # This method is mainly used for subtype test in order to sanely compare fixed.
919 # By default, return self.
920 # See the redefinitions for specific behavior in each kind of type.
921 fun lookup_fixed
(mmodule
: MModule, resolved_receiver
: MType): MType do return self
923 # Can the type be resolved?
925 # In order to resolve open types, the formal types must make sence.
935 # E.can_resolve_for(A[Int]) #-> true, E make sense in A
937 # E.can_resolve_for(B[Int]) #-> false, E does not make sense in B
939 # B[E].can_resolve_for(A[F], B[Object]) #-> true,
940 # # B[E] is a red hearing only the E is important,
941 # # E make sense in A
944 # REQUIRE: `anchor != null implies not anchor.need_anchor`
945 # REQUIRE: `mtype.need_anchor implies anchor != null and mtype.can_resolve_for(anchor, null, mmodule)`
946 # ENSURE: `not self.need_anchor implies result == true`
947 fun can_resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule): Bool is abstract
949 # Return the nullable version of the type
950 # If the type is already nullable then self is returned
951 fun as_nullable
: MType
953 var res
= self.as_nullable_cache
954 if res
!= null then return res
955 res
= new MNullableType(self)
956 self.as_nullable_cache
= res
960 # Return the not nullable version of the type
961 # Is the type is already not nullable, then self is returned.
963 # Note: this just remove the `nullable` notation, but the result can still contains null.
964 # For instance if `self isa MNullType` or self is a formal type bounded by a nullable type.
965 fun as_notnullable
: MType
970 private var as_nullable_cache
: nullable MType = null
973 # The depth of the type seen as a tree.
980 # Formal types have a depth of 1.
986 # The length of the type seen as a tree.
993 # Formal types have a length of 1.
999 # Compute all the classdefs inherited/imported.
1000 # The returned set contains:
1001 # * the class definitions from `mmodule` and its imported modules
1002 # * the class definitions of this type and its super-types
1004 # This function is used mainly internally.
1006 # REQUIRE: `not self.need_anchor`
1007 fun collect_mclassdefs
(mmodule
: MModule): Set[MClassDef] is abstract
1009 # Compute all the super-classes.
1010 # This function is used mainly internally.
1012 # REQUIRE: `not self.need_anchor`
1013 fun collect_mclasses
(mmodule
: MModule): Set[MClass] is abstract
1015 # Compute all the declared super-types.
1016 # Super-types are returned as declared in the classdefs (verbatim).
1017 # This function is used mainly internally.
1019 # REQUIRE: `not self.need_anchor`
1020 fun collect_mtypes
(mmodule
: MModule): Set[MClassType] is abstract
1022 # Is the property in self for a given module
1023 # This method does not filter visibility or whatever
1025 # REQUIRE: `not self.need_anchor`
1026 fun has_mproperty
(mmodule
: MModule, mproperty
: MProperty): Bool
1028 assert not self.need_anchor
1029 return self.collect_mclassdefs
(mmodule
).has
(mproperty
.intro_mclassdef
)
1033 # A type based on a class.
1035 # `MClassType` have properties (see `has_mproperty`).
1039 # The associated class
1042 redef fun model
do return self.mclass
.intro_mmodule
.model
1044 # TODO: private init because strongly bounded to its mclass. see `mclass.mclass_type`
1046 # The formal arguments of the type
1047 # ENSURE: `result.length == self.mclass.arity`
1048 var arguments
= new Array[MType]
1050 redef fun to_s
do return mclass
.to_s
1052 redef fun full_name
do return mclass
.full_name
1054 redef fun need_anchor
do return false
1056 redef fun anchor_to
(mmodule
: MModule, anchor
: MClassType): MClassType
1058 return super.as(MClassType)
1061 redef fun resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule, cleanup_virtual
: Bool): MClassType do return self
1063 redef fun can_resolve_for
(mtype
, anchor
, mmodule
) do return true
1065 redef fun collect_mclassdefs
(mmodule
)
1067 assert not self.need_anchor
1068 var cache
= self.collect_mclassdefs_cache
1069 if not cache
.has_key
(mmodule
) then
1070 self.collect_things
(mmodule
)
1072 return cache
[mmodule
]
1075 redef fun collect_mclasses
(mmodule
)
1077 if collect_mclasses_last_module
== mmodule
then return collect_mclasses_last_module_cache
1078 assert not self.need_anchor
1079 var cache
= self.collect_mclasses_cache
1080 if not cache
.has_key
(mmodule
) then
1081 self.collect_things
(mmodule
)
1083 var res
= cache
[mmodule
]
1084 collect_mclasses_last_module
= mmodule
1085 collect_mclasses_last_module_cache
= res
1089 private var collect_mclasses_last_module
: nullable MModule = null
1090 private var collect_mclasses_last_module_cache
: Set[MClass] is noinit
1092 redef fun collect_mtypes
(mmodule
)
1094 assert not self.need_anchor
1095 var cache
= self.collect_mtypes_cache
1096 if not cache
.has_key
(mmodule
) then
1097 self.collect_things
(mmodule
)
1099 return cache
[mmodule
]
1102 # common implementation for `collect_mclassdefs`, `collect_mclasses`, and `collect_mtypes`.
1103 private fun collect_things
(mmodule
: MModule)
1105 var res
= new HashSet[MClassDef]
1106 var seen
= new HashSet[MClass]
1107 var types
= new HashSet[MClassType]
1108 seen
.add
(self.mclass
)
1109 var todo
= [self.mclass
]
1110 while not todo
.is_empty
do
1111 var mclass
= todo
.pop
1112 #print "process {mclass}"
1113 for mclassdef
in mclass
.mclassdefs
do
1114 if not mmodule
.in_importation
<= mclassdef
.mmodule
then continue
1115 #print " process {mclassdef}"
1117 for supertype
in mclassdef
.supertypes
do
1118 types
.add
(supertype
)
1119 var superclass
= supertype
.mclass
1120 if seen
.has
(superclass
) then continue
1121 #print " add {superclass}"
1122 seen
.add
(superclass
)
1123 todo
.add
(superclass
)
1127 collect_mclassdefs_cache
[mmodule
] = res
1128 collect_mclasses_cache
[mmodule
] = seen
1129 collect_mtypes_cache
[mmodule
] = types
1132 private var collect_mclassdefs_cache
= new HashMap[MModule, Set[MClassDef]]
1133 private var collect_mclasses_cache
= new HashMap[MModule, Set[MClass]]
1134 private var collect_mtypes_cache
= new HashMap[MModule, Set[MClassType]]
1138 # A type based on a generic class.
1139 # A generic type a just a class with additional formal generic arguments.
1145 # TODO: private init because strongly bounded to its mclass. see `mclass.get_mtype`
1149 assert self.mclass
.arity
== arguments
.length
1151 self.need_anchor
= false
1152 for t
in arguments
do
1153 if t
.need_anchor
then
1154 self.need_anchor
= true
1159 self.to_s
= "{mclass}[{arguments.join(", ")}]"
1162 # The short-name of the class, then the full-name of each type arguments within brackets.
1163 # Example: `"Map[String, List[Int]]"`
1164 redef var to_s
: String is noinit
1166 # The full-name of the class, then the full-name of each type arguments within brackets.
1167 # Example: `"standard::Map[standard::String, standard::List[standard::Int]]"`
1168 redef var full_name
is lazy
do
1169 var args
= new Array[String]
1170 for t
in arguments
do
1171 args
.add t
.full_name
1173 return "{mclass.full_name}[{args.join(", ")}]}"
1176 redef var need_anchor
: Bool is noinit
1178 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1180 if not need_anchor
then return self
1181 assert can_resolve_for
(mtype
, anchor
, mmodule
)
1182 var types
= new Array[MType]
1183 for t
in arguments
do
1184 types
.add
(t
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
))
1186 return mclass
.get_mtype
(types
)
1189 redef fun can_resolve_for
(mtype
, anchor
, mmodule
)
1191 if not need_anchor
then return true
1192 for t
in arguments
do
1193 if not t
.can_resolve_for
(mtype
, anchor
, mmodule
) then return false
1202 for a
in self.arguments
do
1204 if d
> dmax
then dmax
= d
1212 for a
in self.arguments
do
1219 # A virtual formal type.
1223 # The property associated with the type.
1224 # Its the definitions of this property that determine the bound or the virtual type.
1225 var mproperty
: MVirtualTypeProp
1227 redef fun model
do return self.mproperty
.intro_mclassdef
.mmodule
.model
1229 redef fun lookup_bound
(mmodule
: MModule, resolved_receiver
: MType): MType
1231 return lookup_single_definition
(mmodule
, resolved_receiver
).bound
.as(not null)
1234 private fun lookup_single_definition
(mmodule
: MModule, resolved_receiver
: MType): MVirtualTypeDef
1236 assert not resolved_receiver
.need_anchor
1237 var props
= self.mproperty
.lookup_definitions
(mmodule
, resolved_receiver
)
1238 if props
.is_empty
then
1240 else if props
.length
== 1 then
1243 var types
= new ArraySet[MType]
1244 var res
= props
.first
1246 types
.add
(p
.bound
.as(not null))
1247 if not res
.is_fixed
then res
= p
1249 if types
.length
== 1 then
1255 # A VT is fixed when:
1256 # * the VT is (re-)defined with the annotation `is fixed`
1257 # * the VT is (indirectly) bound to an enum class (see `enum_kind`) since there is no subtype possible
1258 # * the receiver is an enum class since there is no subtype possible
1259 redef fun lookup_fixed
(mmodule
: MModule, resolved_receiver
: MType): MType
1261 assert not resolved_receiver
.need_anchor
1262 resolved_receiver
= resolved_receiver
.as_notnullable
1263 assert resolved_receiver
isa MClassType # It is the only remaining type
1265 var prop
= lookup_single_definition
(mmodule
, resolved_receiver
)
1266 var res
= prop
.bound
.as(not null)
1268 # Recursively lookup the fixed result
1269 res
= res
.lookup_fixed
(mmodule
, resolved_receiver
)
1271 # 1. For a fixed VT, return the resolved bound
1272 if prop
.is_fixed
then return res
1274 # 2. For a enum boud, return the bound
1275 if res
isa MClassType and res
.mclass
.kind
== enum_kind
then return res
1277 # 3. for a enum receiver return the bound
1278 if resolved_receiver
.mclass
.kind
== enum_kind
then return res
1283 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1285 if not cleanup_virtual
then return self
1286 assert can_resolve_for
(mtype
, anchor
, mmodule
)
1287 # self is a virtual type declared (or inherited) in mtype
1288 # The point of the function it to get the bound of the virtual type that make sense for mtype
1289 # But because mtype is maybe a virtual/formal type, we need to get a real receiver first
1290 #print "{class_name}: {self}/{mtype}/{anchor}?"
1291 var resolved_receiver
1292 if mtype
.need_anchor
then
1293 assert anchor
!= null
1294 resolved_receiver
= mtype
.resolve_for
(anchor
, null, mmodule
, true)
1296 resolved_receiver
= mtype
1298 # Now, we can get the bound
1299 var verbatim_bound
= lookup_bound
(mmodule
, resolved_receiver
)
1300 # The bound is exactly as declared in the "type" property, so we must resolve it again
1301 var res
= verbatim_bound
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1306 redef fun can_resolve_for
(mtype
, anchor
, mmodule
)
1308 if mtype
.need_anchor
then
1309 assert anchor
!= null
1310 mtype
= mtype
.anchor_to
(mmodule
, anchor
)
1312 return mtype
.has_mproperty
(mmodule
, mproperty
)
1315 redef fun to_s
do return self.mproperty
.to_s
1317 redef fun full_name
do return self.mproperty
.full_name
1320 # The type associated to a formal parameter generic type of a class
1322 # Each parameter type is associated to a specific class.
1323 # It means that all refinements of a same class "share" the parameter type,
1324 # but that a generic subclass has its own parameter types.
1326 # However, in the sense of the meta-model, a parameter type of a class is
1327 # a valid type in a subclass. The "in the sense of the meta-model" is
1328 # important because, in the Nit language, the programmer cannot refers
1329 # directly to the parameter types of the super-classes.
1334 # fun e: E is abstract
1340 # In the class definition B[F], `F` is a valid type but `E` is not.
1341 # However, `self.e` is a valid method call, and the signature of `e` is
1344 # Note that parameter types are shared among class refinements.
1345 # Therefore parameter only have an internal name (see `to_s` for details).
1346 class MParameterType
1349 # The generic class where the parameter belong
1352 redef fun model
do return self.mclass
.intro_mmodule
.model
1354 # The position of the parameter (0 for the first parameter)
1355 # FIXME: is `position` a better name?
1360 redef fun to_s
do return name
1362 redef var full_name
is lazy
do return "{mclass.full_name}::{name}"
1364 redef fun lookup_bound
(mmodule
: MModule, resolved_receiver
: MType): MType
1366 assert not resolved_receiver
.need_anchor
1367 resolved_receiver
= resolved_receiver
.as_notnullable
1368 assert resolved_receiver
isa MClassType # It is the only remaining type
1369 var goalclass
= self.mclass
1370 if resolved_receiver
.mclass
== goalclass
then
1371 return resolved_receiver
.arguments
[self.rank
]
1373 var supertypes
= resolved_receiver
.collect_mtypes
(mmodule
)
1374 for t
in supertypes
do
1375 if t
.mclass
== goalclass
then
1376 # Yeah! c specialize goalclass with a "super `t'". So the question is what is the argument of f
1377 # FIXME: Here, we stop on the first goal. Should we check others and detect inconsistencies?
1378 var res
= t
.arguments
[self.rank
]
1385 # A PT is fixed when:
1386 # * Its bound is a enum class (see `enum_kind`).
1387 # The PT is just useless, but it is still a case.
1388 # * More usually, the `resolved_receiver` is a subclass of `self.mclass`,
1389 # so it is necessarily fixed in a `super` clause, either with a normal type
1390 # or with another PT.
1391 # See `resolve_for` for examples about related issues.
1392 redef fun lookup_fixed
(mmodule
: MModule, resolved_receiver
: MType): MType
1394 assert not resolved_receiver
.need_anchor
1395 resolved_receiver
= resolved_receiver
.as_notnullable
1396 assert resolved_receiver
isa MClassType # It is the only remaining type
1397 var res
= self.resolve_for
(resolved_receiver
.mclass
.mclass_type
, resolved_receiver
, mmodule
, false)
1401 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1403 assert can_resolve_for
(mtype
, anchor
, mmodule
)
1404 #print "{class_name}: {self}/{mtype}/{anchor}?"
1406 if mtype
isa MGenericType and mtype
.mclass
== self.mclass
then
1407 var res
= mtype
.arguments
[self.rank
]
1408 if anchor
!= null and res
.need_anchor
then
1409 # Maybe the result can be resolved more if are bound to a final class
1410 var r2
= res
.anchor_to
(mmodule
, anchor
)
1411 if r2
isa MClassType and r2
.mclass
.kind
== enum_kind
then return r2
1416 # self is a parameter type of mtype (or of a super-class of mtype)
1417 # The point of the function it to get the bound of the virtual type that make sense for mtype
1418 # But because mtype is maybe a virtual/formal type, we need to get a real receiver first
1419 # FIXME: What happens here is far from clear. Thus this part must be validated and clarified
1420 var resolved_receiver
1421 if mtype
.need_anchor
then
1422 assert anchor
!= null
1423 resolved_receiver
= mtype
.resolve_for
(anchor
.mclass
.mclass_type
, anchor
, mmodule
, true)
1425 resolved_receiver
= mtype
1427 if resolved_receiver
isa MNullableType then resolved_receiver
= resolved_receiver
.mtype
1428 if resolved_receiver
isa MParameterType then
1429 assert resolved_receiver
.mclass
== anchor
.mclass
1430 resolved_receiver
= anchor
.arguments
[resolved_receiver
.rank
]
1431 if resolved_receiver
isa MNullableType then resolved_receiver
= resolved_receiver
.mtype
1433 assert resolved_receiver
isa MClassType # It is the only remaining type
1435 # Eh! The parameter is in the current class.
1436 # So we return the corresponding argument, no mater what!
1437 if resolved_receiver
.mclass
== self.mclass
then
1438 var res
= resolved_receiver
.arguments
[self.rank
]
1439 #print "{class_name}: {self}/{mtype}/{anchor} -> direct {res}"
1443 if resolved_receiver
.need_anchor
then
1444 assert anchor
!= null
1445 resolved_receiver
= resolved_receiver
.resolve_for
(anchor
, null, mmodule
, false)
1447 # Now, we can get the bound
1448 var verbatim_bound
= lookup_bound
(mmodule
, resolved_receiver
)
1449 # The bound is exactly as declared in the "type" property, so we must resolve it again
1450 var res
= verbatim_bound
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1452 #print "{class_name}: {self}/{mtype}/{anchor} -> indirect {res}"
1457 redef fun can_resolve_for
(mtype
, anchor
, mmodule
)
1459 if mtype
.need_anchor
then
1460 assert anchor
!= null
1461 mtype
= mtype
.anchor_to
(mmodule
, anchor
)
1463 return mtype
.collect_mclassdefs
(mmodule
).has
(mclass
.intro
)
1467 # A type prefixed with "nullable"
1471 # The base type of the nullable type
1474 redef fun model
do return self.mtype
.model
1478 self.to_s
= "nullable {mtype}"
1481 redef var to_s
: String is noinit
1483 redef var full_name
is lazy
do return "nullable {mtype.full_name}"
1485 redef fun need_anchor
do return mtype
.need_anchor
1486 redef fun as_nullable
do return self
1487 redef fun as_notnullable
do return mtype
1488 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1490 var res
= self.mtype
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1491 return res
.as_nullable
1494 redef fun can_resolve_for
(mtype
, anchor
, mmodule
)
1496 return self.mtype
.can_resolve_for
(mtype
, anchor
, mmodule
)
1499 # Efficiently returns `mtype.lookup_fixed(mmodule, resolved_receiver).as_nullable`
1500 redef fun lookup_fixed
(mmodule
, resolved_receiver
)
1502 var t
= mtype
.lookup_fixed
(mmodule
, resolved_receiver
)
1503 if t
== mtype
then return self
1504 return t
.as_nullable
1507 redef fun depth
do return self.mtype
.depth
1509 redef fun length
do return self.mtype
.length
1511 redef fun collect_mclassdefs
(mmodule
)
1513 assert not self.need_anchor
1514 return self.mtype
.collect_mclassdefs
(mmodule
)
1517 redef fun collect_mclasses
(mmodule
)
1519 assert not self.need_anchor
1520 return self.mtype
.collect_mclasses
(mmodule
)
1523 redef fun collect_mtypes
(mmodule
)
1525 assert not self.need_anchor
1526 return self.mtype
.collect_mtypes
(mmodule
)
1530 # The type of the only value null
1532 # The is only one null type per model, see `MModel::null_type`.
1535 redef var model
: Model
1536 redef fun to_s
do return "null"
1537 redef fun full_name
do return "null"
1538 redef fun as_nullable
do return self
1539 redef fun need_anchor
do return false
1540 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
) do return self
1541 redef fun can_resolve_for
(mtype
, anchor
, mmodule
) do return true
1543 redef fun collect_mclassdefs
(mmodule
) do return new HashSet[MClassDef]
1545 redef fun collect_mclasses
(mmodule
) do return new HashSet[MClass]
1547 redef fun collect_mtypes
(mmodule
) do return new HashSet[MClassType]
1550 # A signature of a method
1554 # The each parameter (in order)
1555 var mparameters
: Array[MParameter]
1557 # The return type (null for a procedure)
1558 var return_mtype
: nullable MType
1563 var t
= self.return_mtype
1564 if t
!= null then dmax
= t
.depth
1565 for p
in mparameters
do
1566 var d
= p
.mtype
.depth
1567 if d
> dmax
then dmax
= d
1575 var t
= self.return_mtype
1576 if t
!= null then res
+= t
.length
1577 for p
in mparameters
do
1578 res
+= p
.mtype
.length
1583 # REQUIRE: 1 <= mparameters.count p -> p.is_vararg
1586 var vararg_rank
= -1
1587 for i
in [0..mparameters
.length
[ do
1588 var parameter
= mparameters
[i
]
1589 if parameter
.is_vararg
then
1590 assert vararg_rank
== -1
1594 self.vararg_rank
= vararg_rank
1597 # The rank of the ellipsis (`...`) for vararg (starting from 0).
1598 # value is -1 if there is no vararg.
1599 # Example: for "(a: Int, b: Bool..., c: Char)" #-> vararg_rank=1
1600 var vararg_rank
: Int is noinit
1602 # The number or parameters
1603 fun arity
: Int do return mparameters
.length
1607 var b
= new FlatBuffer
1608 if not mparameters
.is_empty
then
1610 for i
in [0..mparameters
.length
[ do
1611 var mparameter
= mparameters
[i
]
1612 if i
> 0 then b
.append
(", ")
1613 b
.append
(mparameter
.name
)
1615 b
.append
(mparameter
.mtype
.to_s
)
1616 if mparameter
.is_vararg
then
1622 var ret
= self.return_mtype
1630 redef fun resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule, cleanup_virtual
: Bool): MSignature
1632 var params
= new Array[MParameter]
1633 for p
in self.mparameters
do
1634 params
.add
(p
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
))
1636 var ret
= self.return_mtype
1638 ret
= ret
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1640 var res
= new MSignature(params
, ret
)
1645 # A parameter in a signature
1649 # The name of the parameter
1650 redef var name
: String
1652 # The static type of the parameter
1655 # Is the parameter a vararg?
1661 return "{name}: {mtype}..."
1663 return "{name}: {mtype}"
1667 fun resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule, cleanup_virtual
: Bool): MParameter
1669 if not self.mtype
.need_anchor
then return self
1670 var newtype
= self.mtype
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1671 var res
= new MParameter(self.name
, newtype
, self.is_vararg
)
1675 redef fun model
do return mtype
.model
1678 # A service (global property) that generalize method, attribute, etc.
1680 # `MProperty` are global to the model; it means that a `MProperty` is not bound
1681 # to a specific `MModule` nor a specific `MClass`.
1683 # A MProperty gather definitions (see `mpropdefs`) ; one for the introduction
1684 # and the other in subclasses and in refinements.
1686 # A `MProperty` is used to denotes services in polymorphic way (ie. independent
1687 # of any dynamic type).
1688 # For instance, a call site "x.foo" is associated to a `MProperty`.
1689 abstract class MProperty
1692 # The associated MPropDef subclass.
1693 # The two specialization hierarchy are symmetric.
1694 type MPROPDEF: MPropDef
1696 # The classdef that introduce the property
1697 # While a property is not bound to a specific module, or class,
1698 # the introducing mclassdef is used for naming and visibility
1699 var intro_mclassdef
: MClassDef
1701 # The (short) name of the property
1702 redef var name
: String
1704 # The canonical name of the property.
1706 # It is the short-`name` prefixed by the short-name of the class and the full-name of the module.
1707 # Example: "my_project::my_module::MyClass::my_method"
1708 redef var full_name
is lazy
do
1709 return "{intro_mclassdef.mmodule.full_name}::{intro_mclassdef.mclass.name}::{name}"
1712 # The visibility of the property
1713 var visibility
: MVisibility
1717 intro_mclassdef
.intro_mproperties
.add
(self)
1718 var model
= intro_mclassdef
.mmodule
.model
1719 model
.mproperties_by_name
.add_one
(name
, self)
1720 model
.mproperties
.add
(self)
1723 # All definitions of the property.
1724 # The first is the introduction,
1725 # The other are redefinitions (in refinements and in subclasses)
1726 var mpropdefs
= new Array[MPROPDEF]
1728 # The definition that introduces the property.
1730 # Warning: such a definition may not exist in the early life of the object.
1731 # In this case, the method will abort.
1732 var intro
: MPROPDEF is noinit
1734 redef fun model
do return intro
.model
1737 redef fun to_s
do return name
1739 # Return the most specific property definitions defined or inherited by a type.
1740 # The selection knows that refinement is stronger than specialization;
1741 # however, in case of conflict more than one property are returned.
1742 # If mtype does not know mproperty then an empty array is returned.
1744 # If you want the really most specific property, then look at `lookup_first_definition`
1745 fun lookup_definitions
(mmodule
: MModule, mtype
: MType): Array[MPROPDEF]
1747 assert not mtype
.need_anchor
1748 mtype
= mtype
.as_notnullable
1750 var cache
= self.lookup_definitions_cache
[mmodule
, mtype
]
1751 if cache
!= null then return cache
1753 #print "select prop {mproperty} for {mtype} in {self}"
1754 # First, select all candidates
1755 var candidates
= new Array[MPROPDEF]
1756 for mpropdef
in self.mpropdefs
do
1757 # If the definition is not imported by the module, then skip
1758 if not mmodule
.in_importation
<= mpropdef
.mclassdef
.mmodule
then continue
1759 # If the definition is not inherited by the type, then skip
1760 if not mtype
.is_subtype
(mmodule
, null, mpropdef
.mclassdef
.bound_mtype
) then continue
1762 candidates
.add
(mpropdef
)
1764 # Fast track for only one candidate
1765 if candidates
.length
<= 1 then
1766 self.lookup_definitions_cache
[mmodule
, mtype
] = candidates
1770 # Second, filter the most specific ones
1771 return select_most_specific
(mmodule
, candidates
)
1774 private var lookup_definitions_cache
= new HashMap2[MModule, MType, Array[MPROPDEF]]
1776 # Return the most specific property definitions inherited by a type.
1777 # The selection knows that refinement is stronger than specialization;
1778 # however, in case of conflict more than one property are returned.
1779 # If mtype does not know mproperty then an empty array is returned.
1781 # If you want the really most specific property, then look at `lookup_next_definition`
1783 # FIXME: Move to `MPropDef`?
1784 fun lookup_super_definitions
(mmodule
: MModule, mtype
: MType): Array[MPROPDEF]
1786 assert not mtype
.need_anchor
1787 mtype
= mtype
.as_notnullable
1789 # First, select all candidates
1790 var candidates
= new Array[MPROPDEF]
1791 for mpropdef
in self.mpropdefs
do
1792 # If the definition is not imported by the module, then skip
1793 if not mmodule
.in_importation
<= mpropdef
.mclassdef
.mmodule
then continue
1794 # If the definition is not inherited by the type, then skip
1795 if not mtype
.is_subtype
(mmodule
, null, mpropdef
.mclassdef
.bound_mtype
) then continue
1796 # If the definition is defined by the type, then skip (we want the super, so e skip the current)
1797 if mtype
== mpropdef
.mclassdef
.bound_mtype
and mmodule
== mpropdef
.mclassdef
.mmodule
then continue
1799 candidates
.add
(mpropdef
)
1801 # Fast track for only one candidate
1802 if candidates
.length
<= 1 then return candidates
1804 # Second, filter the most specific ones
1805 return select_most_specific
(mmodule
, candidates
)
1808 # Return an array containing olny the most specific property definitions
1809 # This is an helper function for `lookup_definitions` and `lookup_super_definitions`
1810 private fun select_most_specific
(mmodule
: MModule, candidates
: Array[MPROPDEF]): Array[MPROPDEF]
1812 var res
= new Array[MPROPDEF]
1813 for pd1
in candidates
do
1814 var cd1
= pd1
.mclassdef
1817 for pd2
in candidates
do
1818 if pd2
== pd1
then continue # do not compare with self!
1819 var cd2
= pd2
.mclassdef
1821 if c2
.mclass_type
== c1
.mclass_type
then
1822 if cd2
.mmodule
.in_importation
< cd1
.mmodule
then
1823 # cd2 refines cd1; therefore we skip pd1
1827 else if cd2
.bound_mtype
.is_subtype
(mmodule
, null, cd1
.bound_mtype
) and cd2
.bound_mtype
!= cd1
.bound_mtype
then
1828 # cd2 < cd1; therefore we skip pd1
1837 if res
.is_empty
then
1838 print
"All lost! {candidates.join(", ")}"
1839 # FIXME: should be abort!
1844 # Return the most specific definition in the linearization of `mtype`.
1846 # If you want to know the next properties in the linearization,
1847 # look at `MPropDef::lookup_next_definition`.
1849 # FIXME: the linearization is still unspecified
1851 # REQUIRE: `not mtype.need_anchor`
1852 # REQUIRE: `mtype.has_mproperty(mmodule, self)`
1853 fun lookup_first_definition
(mmodule
: MModule, mtype
: MType): MPROPDEF
1855 assert mtype
.has_mproperty
(mmodule
, self)
1856 return lookup_all_definitions
(mmodule
, mtype
).first
1859 # Return all definitions in a linearization order
1860 # Most specific first, most general last
1861 fun lookup_all_definitions
(mmodule
: MModule, mtype
: MType): Array[MPROPDEF]
1863 assert not mtype
.need_anchor
1864 mtype
= mtype
.as_notnullable
1866 var cache
= self.lookup_all_definitions_cache
[mmodule
, mtype
]
1867 if cache
!= null then return cache
1869 #print "select prop {mproperty} for {mtype} in {self}"
1870 # First, select all candidates
1871 var candidates
= new Array[MPROPDEF]
1872 for mpropdef
in self.mpropdefs
do
1873 # If the definition is not imported by the module, then skip
1874 if not mmodule
.in_importation
<= mpropdef
.mclassdef
.mmodule
then continue
1875 # If the definition is not inherited by the type, then skip
1876 if not mtype
.is_subtype
(mmodule
, null, mpropdef
.mclassdef
.bound_mtype
) then continue
1878 candidates
.add
(mpropdef
)
1880 # Fast track for only one candidate
1881 if candidates
.length
<= 1 then
1882 self.lookup_all_definitions_cache
[mmodule
, mtype
] = candidates
1886 mmodule
.linearize_mpropdefs
(candidates
)
1887 candidates
= candidates
.reversed
1888 self.lookup_all_definitions_cache
[mmodule
, mtype
] = candidates
1892 private var lookup_all_definitions_cache
= new HashMap2[MModule, MType, Array[MPROPDEF]]
1899 redef type MPROPDEF: MMethodDef
1901 # Is the property defined at the top_level of the module?
1902 # Currently such a property are stored in `Object`
1903 var is_toplevel
: Bool = false is writable
1905 # Is the property a constructor?
1906 # Warning, this property can be inherited by subclasses with or without being a constructor
1907 # therefore, you should use `is_init_for` the verify if the property is a legal constructor for a given class
1908 var is_init
: Bool = false is writable
1910 # The constructor is a (the) root init with empty signature but a set of initializers
1911 var is_root_init
: Bool = false is writable
1913 # Is the property a 'new' constructor?
1914 var is_new
: Bool = false is writable
1916 # Is the property a legal constructor for a given class?
1917 # As usual, visibility is not considered.
1918 # FIXME not implemented
1919 fun is_init_for
(mclass
: MClass): Bool
1925 # A global attribute
1929 redef type MPROPDEF: MAttributeDef
1933 # A global virtual type
1934 class MVirtualTypeProp
1937 redef type MPROPDEF: MVirtualTypeDef
1939 # The formal type associated to the virtual type property
1940 var mvirtualtype
= new MVirtualType(self)
1943 # A definition of a property (local property)
1945 # Unlike `MProperty`, a `MPropDef` is a local definition that belong to a
1946 # specific class definition (which belong to a specific module)
1947 abstract class MPropDef
1950 # The associated `MProperty` subclass.
1951 # the two specialization hierarchy are symmetric
1952 type MPROPERTY: MProperty
1955 type MPROPDEF: MPropDef
1957 # The class definition where the property definition is
1958 var mclassdef
: MClassDef
1960 # The associated global property
1961 var mproperty
: MPROPERTY
1963 # The origin of the definition
1964 var location
: Location
1968 mclassdef
.mpropdefs
.add
(self)
1969 mproperty
.mpropdefs
.add
(self)
1970 if mproperty
.intro_mclassdef
== mclassdef
then
1971 assert not isset mproperty
._intro
1972 mproperty
.intro
= self
1974 self.to_s
= "{mclassdef}#{mproperty}"
1977 # Actually the name of the `mproperty`
1978 redef fun name
do return mproperty
.name
1980 # The full-name of mpropdefs combine the information about the `classdef` and the `mproperty`.
1982 # Therefore the combination of identifiers is awful,
1983 # the worst case being
1986 # "{mclassdef.mmodule.full_name}#{mclassdef.mclass.intro_mmodule.full_name}::{mclassdef.name}#{mproperty.intro_mclassdef.mmodule.full_name}::{mproperty.intro_mclassdef.name}::{name}"
1989 # Fortunately, the full-name is simplified when entities are repeated.
1990 # The simplest form is "my_module#MyClass#my_property".
1991 redef var full_name
is lazy
do
1992 var res
= new FlatBuffer
1993 res
.append mclassdef
.mmodule
.full_name
1995 if not mclassdef
.is_intro
then
1996 res
.append mclassdef
.mclass
.intro_mmodule
.full_name
1999 res
.append mclassdef
.name
2001 if mproperty
.intro_mclassdef
.mmodule
!= mclassdef
.mmodule
then
2002 res
.append mproperty
.intro_mclassdef
.mmodule
.full_name
2005 if mclassdef
.mclass
!= mproperty
.intro_mclassdef
.mclass
then
2006 res
.append mproperty
.intro_mclassdef
.mclass
.name
2013 redef fun model
do return mclassdef
.model
2015 # Internal name combining the module, the class and the property
2016 # Example: "mymodule#MyClass#mymethod"
2017 redef var to_s
: String is noinit
2019 # Is self the definition that introduce the property?
2020 fun is_intro
: Bool do return mproperty
.intro
== self
2022 # Return the next definition in linearization of `mtype`.
2024 # This method is used to determine what method is called by a super.
2026 # REQUIRE: `not mtype.need_anchor`
2027 fun lookup_next_definition
(mmodule
: MModule, mtype
: MType): MPROPDEF
2029 assert not mtype
.need_anchor
2031 var mpropdefs
= self.mproperty
.lookup_all_definitions
(mmodule
, mtype
)
2032 var i
= mpropdefs
.iterator
2033 while i
.is_ok
and i
.item
!= self do i
.next
2034 assert has_property
: i
.is_ok
2036 assert has_next_property
: i
.is_ok
2041 # A local definition of a method
2045 redef type MPROPERTY: MMethod
2046 redef type MPROPDEF: MMethodDef
2048 # The signature attached to the property definition
2049 var msignature
: nullable MSignature = null is writable
2051 # The signature attached to the `new` call on a root-init
2052 # This is a concatenation of the signatures of the initializers
2054 # REQUIRE `mproperty.is_root_init == (new_msignature != null)`
2055 var new_msignature
: nullable MSignature = null is writable
2057 # List of initialisers to call in root-inits
2059 # They could be setters or attributes
2061 # REQUIRE `mproperty.is_root_init == (new_msignature != null)`
2062 var initializers
= new Array[MProperty]
2064 # Is the method definition abstract?
2065 var is_abstract
: Bool = false is writable
2067 # Is the method definition intern?
2068 var is_intern
= false is writable
2070 # Is the method definition extern?
2071 var is_extern
= false is writable
2073 # An optional constant value returned in functions.
2075 # Only some specific primitife value are accepted by engines.
2076 # Is used when there is no better implementation available.
2078 # Currently used only for the implementation of the `--define`
2079 # command-line option.
2080 # SEE: module `mixin`.
2081 var constant_value
: nullable Object = null is writable
2084 # A local definition of an attribute
2088 redef type MPROPERTY: MAttribute
2089 redef type MPROPDEF: MAttributeDef
2091 # The static type of the attribute
2092 var static_mtype
: nullable MType = null is writable
2095 # A local definition of a virtual type
2096 class MVirtualTypeDef
2099 redef type MPROPERTY: MVirtualTypeProp
2100 redef type MPROPDEF: MVirtualTypeDef
2102 # The bound of the virtual type
2103 var bound
: nullable MType = null is writable
2105 # Is the bound fixed?
2106 var is_fixed
= false is writable
2113 # * `interface_kind`
2117 # Note this class is basically an enum.
2118 # FIXME: use a real enum once user-defined enums are available
2120 redef var to_s
: String
2122 # Is a constructor required?
2125 # TODO: private init because enumeration.
2127 # Can a class of kind `self` specializes a class of kine `other`?
2128 fun can_specialize
(other
: MClassKind): Bool
2130 if other
== interface_kind
then return true # everybody can specialize interfaces
2131 if self == interface_kind
or self == enum_kind
then
2132 # no other case for interfaces
2134 else if self == extern_kind
then
2135 # only compatible with themselves
2136 return self == other
2137 else if other
== enum_kind
or other
== extern_kind
then
2138 # abstract_kind and concrete_kind are incompatible
2141 # remain only abstract_kind and concrete_kind
2146 # The class kind `abstract`
2147 fun abstract_kind
: MClassKind do return once
new MClassKind("abstract class", true)
2148 # The class kind `concrete`
2149 fun concrete_kind
: MClassKind do return once
new MClassKind("class", true)
2150 # The class kind `interface`
2151 fun interface_kind
: MClassKind do return once
new MClassKind("interface", false)
2152 # The class kind `enum`
2153 fun enum_kind
: MClassKind do return once
new MClassKind("enum", false)
2154 # The class kind `extern`
2155 fun extern_kind
: MClassKind do return once
new MClassKind("extern class", false)