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 return mclasses_by_name
.get_or_null
(name
)
80 # Collections of properties grouped by their short name
81 private var mproperties_by_name
= new MultiHashMap[String, MProperty]
83 # Return all properties named `name`.
85 # If such a property does not exist, null is returned
86 # (instead of an empty array)
88 # Visibility or modules are not considered
89 fun get_mproperties_by_name
(name
: String): nullable Array[MProperty]
91 return mproperties_by_name
.get_or_null
(name
)
95 var null_type
= new MNullType(self)
97 # Build an ordered tree with from `concerns`
98 fun concerns_tree
(mconcerns
: Collection[MConcern]): ConcernsTree do
99 var seen
= new HashSet[MConcern]
100 var res
= new ConcernsTree
102 var todo
= new Array[MConcern]
103 todo
.add_all mconcerns
105 while not todo
.is_empty
do
107 if seen
.has
(c
) then continue
108 var pc
= c
.parent_concern
122 # An OrderedTree that can be easily refined for display purposes
124 super OrderedTree[MConcern]
128 # All the classes introduced in the module
129 var intro_mclasses
= new Array[MClass]
131 # All the class definitions of the module
132 # (introduction and refinement)
133 var mclassdefs
= new Array[MClassDef]
135 # Does the current module has a given class `mclass`?
136 # Return true if the mmodule introduces, refines or imports a class.
137 # Visibility is not considered.
138 fun has_mclass
(mclass
: MClass): Bool
140 return self.in_importation
<= mclass
.intro_mmodule
143 # Full hierarchy of introduced ans imported classes.
145 # Create a new hierarchy got by flattening the classes for the module
146 # and its imported modules.
147 # Visibility is not considered.
149 # Note: this function is expensive and is usually used for the main
150 # module of a program only. Do not use it to do you own subtype
152 fun flatten_mclass_hierarchy
: POSet[MClass]
154 var res
= self.flatten_mclass_hierarchy_cache
155 if res
!= null then return res
156 res
= new POSet[MClass]
157 for m
in self.in_importation
.greaters
do
158 for cd
in m
.mclassdefs
do
161 for s
in cd
.supertypes
do
162 res
.add_edge
(c
, s
.mclass
)
166 self.flatten_mclass_hierarchy_cache
= res
170 # Sort a given array of classes using the linearization order of the module
171 # The most general is first, the most specific is last
172 fun linearize_mclasses
(mclasses
: Array[MClass])
174 self.flatten_mclass_hierarchy
.sort
(mclasses
)
177 # Sort a given array of class definitions using the linearization order of the module
178 # the refinement link is stronger than the specialisation link
179 # The most general is first, the most specific is last
180 fun linearize_mclassdefs
(mclassdefs
: Array[MClassDef])
182 var sorter
= new MClassDefSorter(self)
183 sorter
.sort
(mclassdefs
)
186 # Sort a given array of property definitions using the linearization order of the module
187 # the refinement link is stronger than the specialisation link
188 # The most general is first, the most specific is last
189 fun linearize_mpropdefs
(mpropdefs
: Array[MPropDef])
191 var sorter
= new MPropDefSorter(self)
192 sorter
.sort
(mpropdefs
)
195 private var flatten_mclass_hierarchy_cache
: nullable POSet[MClass] = null
197 # The primitive type `Object`, the root of the class hierarchy
198 var object_type
: MClassType = self.get_primitive_class
("Object").mclass_type
is lazy
200 # The type `Pointer`, super class to all extern classes
201 var pointer_type
: MClassType = self.get_primitive_class
("Pointer").mclass_type
is lazy
203 # The primitive type `Bool`
204 var bool_type
: MClassType = self.get_primitive_class
("Bool").mclass_type
is lazy
206 # The primitive type `Int`
207 var int_type
: MClassType = self.get_primitive_class
("Int").mclass_type
is lazy
209 # The primitive type `Byte`
210 var byte_type
: MClassType = self.get_primitive_class
("Byte").mclass_type
is lazy
212 # The primitive type `Int8`
213 var int8_type
: MClassType = self.get_primitive_class
("Int8").mclass_type
is lazy
215 # The primitive type `Int16`
216 var int16_type
: MClassType = self.get_primitive_class
("Int16").mclass_type
is lazy
218 # The primitive type `UInt16`
219 var uint16_type
: MClassType = self.get_primitive_class
("UInt16").mclass_type
is lazy
221 # The primitive type `Int32`
222 var int32_type
: MClassType = self.get_primitive_class
("Int32").mclass_type
is lazy
224 # The primitive type `UInt32`
225 var uint32_type
: MClassType = self.get_primitive_class
("UInt32").mclass_type
is lazy
227 # The primitive type `Char`
228 var char_type
: MClassType = self.get_primitive_class
("Char").mclass_type
is lazy
230 # The primitive type `Float`
231 var float_type
: MClassType = self.get_primitive_class
("Float").mclass_type
is lazy
233 # The primitive type `String`
234 var string_type
: MClassType = self.get_primitive_class
("String").mclass_type
is lazy
236 # The primitive type `NativeString`
237 var native_string_type
: MClassType = self.get_primitive_class
("NativeString").mclass_type
is lazy
239 # A primitive type of `Array`
240 fun array_type
(elt_type
: MType): MClassType do return array_class
.get_mtype
([elt_type
])
242 # The primitive class `Array`
243 var array_class
: MClass = self.get_primitive_class
("Array") is lazy
245 # A primitive type of `NativeArray`
246 fun native_array_type
(elt_type
: MType): MClassType do return native_array_class
.get_mtype
([elt_type
])
248 # The primitive class `NativeArray`
249 var native_array_class
: MClass = self.get_primitive_class
("NativeArray") is lazy
251 # The primitive type `Sys`, the main type of the program, if any
252 fun sys_type
: nullable MClassType
254 var clas
= self.model
.get_mclasses_by_name
("Sys")
255 if clas
== null then return null
256 return get_primitive_class
("Sys").mclass_type
259 # The primitive type `Finalizable`
260 # Used to tag classes that need to be finalized.
261 fun finalizable_type
: nullable MClassType
263 var clas
= self.model
.get_mclasses_by_name
("Finalizable")
264 if clas
== null then return null
265 return get_primitive_class
("Finalizable").mclass_type
268 # Force to get the primitive class named `name` or abort
269 fun get_primitive_class
(name
: String): MClass
271 var cla
= self.model
.get_mclasses_by_name
(name
)
272 # Filter classes by introducing module
273 if cla
!= null then cla
= [for c
in cla
do if self.in_importation
<= c
.intro_mmodule
then c
]
274 if cla
== null or cla
.is_empty
then
275 if name
== "Bool" and self.model
.get_mclasses_by_name
("Object") != null then
276 # Bool is injected because it is needed by engine to code the result
277 # of the implicit casts.
278 var c
= new MClass(self, name
, null, enum_kind
, public_visibility
)
279 var cladef
= new MClassDef(self, c
.mclass_type
, new Location(null, 0,0,0,0))
280 cladef
.set_supertypes
([object_type
])
281 cladef
.add_in_hierarchy
284 print
("Fatal Error: no primitive class {name} in {self}")
288 if cla
.length
!= 1 then
289 var msg
= "Fatal Error: more than one primitive class {name} in {self}:"
290 for c
in cla
do msg
+= " {c.full_name}"
297 # Try to get the primitive method named `name` on the type `recv`
298 fun try_get_primitive_method
(name
: String, recv
: MClass): nullable MMethod
300 var props
= self.model
.get_mproperties_by_name
(name
)
301 if props
== null then return null
302 var res
: nullable MMethod = null
303 var recvtype
= recv
.intro
.bound_mtype
304 for mprop
in props
do
305 assert mprop
isa MMethod
306 if not recvtype
.has_mproperty
(self, mprop
) then continue
309 else if res
!= mprop
then
310 print
("Fatal Error: ambigous property name '{name}'; conflict between {mprop.full_name} and {res.full_name}")
318 private class MClassDefSorter
320 redef type COMPARED: MClassDef
322 redef fun compare
(a
, b
)
326 if ca
!= cb
then return mmodule
.flatten_mclass_hierarchy
.compare
(ca
, cb
)
327 return mmodule
.model
.mclassdef_hierarchy
.compare
(a
, b
)
331 private class MPropDefSorter
333 redef type COMPARED: MPropDef
335 redef fun compare
(pa
, pb
)
341 if ca
!= cb
then return mmodule
.flatten_mclass_hierarchy
.compare
(ca
, cb
)
342 return mmodule
.model
.mclassdef_hierarchy
.compare
(a
, b
)
348 # `MClass` are global to the model; it means that a `MClass` is not bound to a
349 # specific `MModule`.
351 # This characteristic helps the reasoning about classes in a program since a
352 # single `MClass` object always denote the same class.
354 # The drawback is that classes (`MClass`) contain almost nothing by themselves.
355 # These do not really have properties nor belong to a hierarchy since the property and the
356 # hierarchy of a class depends of the refinement in the modules.
358 # Most services on classes require the precision of a module, and no one can asks what are
359 # the super-classes of a class nor what are properties of a class without precising what is
360 # the module considered.
362 # For instance, during the typing of a source-file, the module considered is the module of the file.
363 # eg. the question *is the method `foo` exists in the class `Bar`?* must be reformulated into
364 # *is the method `foo` exists in the class `Bar` in the current module?*
366 # During some global analysis, the module considered may be the main module of the program.
370 # The module that introduce the class
371 # While classes are not bound to a specific module,
372 # the introducing module is used for naming an visibility
373 var intro_mmodule
: MModule
375 # The short name of the class
376 # In Nit, the name of a class cannot evolve in refinements
377 redef var name
: String
379 # The canonical name of the class
381 # It is the name of the class prefixed by the full_name of the `intro_mmodule`
382 # Example: `"owner::module::MyClass"`
383 redef var full_name
is lazy
do
384 return "{self.intro_mmodule.namespace_for(visibility)}::{name}"
387 redef var c_name
is lazy
do
388 return "{intro_mmodule.c_namespace_for(visibility)}__{name.to_cmangle}"
391 # The number of generic formal parameters
392 # 0 if the class is not generic
393 var arity
: Int is noinit
395 # Each generic formal parameters in order.
396 # is empty if the class is not generic
397 var mparameters
= new Array[MParameterType]
399 # A string version of the signature a generic class.
401 # eg. `Map[K: nullable Object, V: nullable Object]`
403 # If the class in non generic the name is just given.
406 fun signature_to_s
: String
408 if arity
== 0 then return name
409 var res
= new FlatBuffer
412 for i
in [0..arity
[ do
413 if i
> 0 then res
.append
", "
414 res
.append mparameters
[i
].name
416 res
.append intro
.bound_mtype
.arguments
[i
].to_s
422 # Initialize `mparameters` from their names.
423 protected fun setup_parameter_names
(parameter_names
: nullable Array[String]) is
426 if parameter_names
== null then
429 self.arity
= parameter_names
.length
432 # Create the formal parameter types
434 assert parameter_names
!= null
435 var mparametertypes
= new Array[MParameterType]
436 for i
in [0..arity
[ do
437 var mparametertype
= new MParameterType(self, i
, parameter_names
[i
])
438 mparametertypes
.add
(mparametertype
)
440 self.mparameters
= mparametertypes
441 var mclass_type
= new MGenericType(self, mparametertypes
)
442 self.mclass_type
= mclass_type
443 self.get_mtype_cache
[mparametertypes
] = mclass_type
445 self.mclass_type
= new MClassType(self)
449 # The kind of the class (interface, abstract class, etc.)
450 # In Nit, the kind of a class cannot evolve in refinements
453 # The visibility of the class
454 # In Nit, the visibility of a class cannot evolve in refinements
455 var visibility
: MVisibility
459 intro_mmodule
.intro_mclasses
.add
(self)
460 var model
= intro_mmodule
.model
461 model
.mclasses_by_name
.add_one
(name
, self)
462 model
.mclasses
.add
(self)
465 redef fun model
do return intro_mmodule
.model
467 # All class definitions (introduction and refinements)
468 var mclassdefs
= new Array[MClassDef]
471 redef fun to_s
do return self.name
473 # The definition that introduces the class.
475 # Warning: such a definition may not exist in the early life of the object.
476 # In this case, the method will abort.
478 # Use `try_intro` instead
479 var intro
: MClassDef is noinit
481 # The definition that introduces the class or null if not yet known.
484 fun try_intro
: nullable MClassDef do
485 if isset _intro
then return _intro
else return null
488 # Return the class `self` in the class hierarchy of the module `mmodule`.
490 # SEE: `MModule::flatten_mclass_hierarchy`
491 # REQUIRE: `mmodule.has_mclass(self)`
492 fun in_hierarchy
(mmodule
: MModule): POSetElement[MClass]
494 return mmodule
.flatten_mclass_hierarchy
[self]
497 # The principal static type of the class.
499 # For non-generic class, mclass_type is the only `MClassType` based
502 # For a generic class, the arguments are the formal parameters.
503 # i.e.: for the class Array[E:Object], the `mclass_type` is Array[E].
504 # If you want Array[Object] the see `MClassDef::bound_mtype`
506 # For generic classes, the mclass_type is also the way to get a formal
507 # generic parameter type.
509 # To get other types based on a generic class, see `get_mtype`.
511 # ENSURE: `mclass_type.mclass == self`
512 var mclass_type
: MClassType is noinit
514 # Return a generic type based on the class
515 # Is the class is not generic, then the result is `mclass_type`
517 # REQUIRE: `mtype_arguments.length == self.arity`
518 fun get_mtype
(mtype_arguments
: Array[MType]): MClassType
520 assert mtype_arguments
.length
== self.arity
521 if self.arity
== 0 then return self.mclass_type
522 var res
= get_mtype_cache
.get_or_null
(mtype_arguments
)
523 if res
!= null then return res
524 res
= new MGenericType(self, mtype_arguments
)
525 self.get_mtype_cache
[mtype_arguments
.to_a
] = res
529 private var get_mtype_cache
= new HashMap[Array[MType], MGenericType]
531 # Is there a `new` factory to allow the pseudo instantiation?
532 var has_new_factory
= false is writable
534 # Is `self` a standard or abstract class kind?
535 var is_class
: Bool is lazy
do return kind
== concrete_kind
or kind
== abstract_kind
537 # Is `self` an interface kind?
538 var is_interface
: Bool is lazy
do return kind
== interface_kind
540 # Is `self` an enum kind?
541 var is_enum
: Bool is lazy
do return kind
== enum_kind
543 # Is `self` and abstract class?
544 var is_abstract
: Bool is lazy
do return kind
== abstract_kind
548 # A definition (an introduction or a refinement) of a class in a module
550 # A `MClassDef` is associated with an explicit (or almost) definition of a
551 # class. Unlike `MClass`, a `MClassDef` is a local definition that belong to
552 # a specific class and a specific module, and contains declarations like super-classes
555 # It is the class definitions that are the backbone of most things in the model:
556 # ClassDefs are defined with regard with other classdefs.
557 # Refinement and specialization are combined to produce a big poset called the `Model::mclassdef_hierarchy`.
559 # Moreover, the extension and the intention of types is defined by looking at the MClassDefs.
563 # The module where the definition is
566 # The associated `MClass`
567 var mclass
: MClass is noinit
569 # The bounded type associated to the mclassdef
571 # For a non-generic class, `bound_mtype` and `mclass.mclass_type`
575 # For the classdef Array[E: Object], the bound_mtype is Array[Object].
576 # If you want Array[E], then see `mclass.mclass_type`
578 # ENSURE: `bound_mtype.mclass == self.mclass`
579 var bound_mtype
: MClassType
581 # The origin of the definition
582 var location
: Location
584 # Internal name combining the module and the class
585 # Example: "mymodule#MyClass"
586 redef var to_s
: String is noinit
590 self.mclass
= bound_mtype
.mclass
591 mmodule
.mclassdefs
.add
(self)
592 mclass
.mclassdefs
.add
(self)
593 if mclass
.intro_mmodule
== mmodule
then
594 assert not isset mclass
._intro
597 self.to_s
= "{mmodule}#{mclass}"
600 # Actually the name of the `mclass`
601 redef fun name
do return mclass
.name
603 # The module and class name separated by a '#'.
605 # The short-name of the class is used for introduction.
606 # Example: "my_module#MyClass"
608 # The full-name of the class is used for refinement.
609 # Example: "my_module#intro_module::MyClass"
610 redef var full_name
is lazy
do
613 # private gives 'p::m#A'
614 return "{mmodule.namespace_for(mclass.visibility)}#{mclass.name}"
615 else if mclass
.intro_mmodule
.mpackage
!= mmodule
.mpackage
then
616 # public gives 'q::n#p::A'
617 # private gives 'q::n#p::m::A'
618 return "{mmodule.full_name}#{mclass.full_name}"
619 else if mclass
.visibility
> private_visibility
then
620 # public gives 'p::n#A'
621 return "{mmodule.full_name}#{mclass.name}"
623 # private gives 'p::n#::m::A' (redundant p is omitted)
624 return "{mmodule.full_name}#::{mclass.intro_mmodule.name}::{mclass.name}"
628 redef var c_name
is lazy
do
630 return "{mmodule.c_namespace_for(mclass.visibility)}___{mclass.c_name}"
631 else if mclass
.intro_mmodule
.mpackage
== mmodule
.mpackage
and mclass
.visibility
> private_visibility
then
632 return "{mmodule.c_name}___{mclass.name.to_cmangle}"
634 return "{mmodule.c_name}___{mclass.c_name}"
638 redef fun model
do return mmodule
.model
640 # All declared super-types
641 # FIXME: quite ugly but not better idea yet
642 var supertypes
= new Array[MClassType]
644 # Register some super-types for the class (ie "super SomeType")
646 # The hierarchy must not already be set
647 # REQUIRE: `self.in_hierarchy == null`
648 fun set_supertypes
(supertypes
: Array[MClassType])
650 assert unique_invocation
: self.in_hierarchy
== null
651 var mmodule
= self.mmodule
652 var model
= mmodule
.model
653 var mtype
= self.bound_mtype
655 for supertype
in supertypes
do
656 self.supertypes
.add
(supertype
)
658 # Register in full_type_specialization_hierarchy
659 model
.full_mtype_specialization_hierarchy
.add_edge
(mtype
, supertype
)
660 # Register in intro_type_specialization_hierarchy
661 if mclass
.intro_mmodule
== mmodule
and supertype
.mclass
.intro_mmodule
== mmodule
then
662 model
.intro_mtype_specialization_hierarchy
.add_edge
(mtype
, supertype
)
668 # Collect the super-types (set by set_supertypes) to build the hierarchy
670 # This function can only invoked once by class
671 # REQUIRE: `self.in_hierarchy == null`
672 # ENSURE: `self.in_hierarchy != null`
675 assert unique_invocation
: self.in_hierarchy
== null
676 var model
= mmodule
.model
677 var res
= model
.mclassdef_hierarchy
.add_node
(self)
678 self.in_hierarchy
= res
679 var mtype
= self.bound_mtype
681 # Here we need to connect the mclassdef to its pairs in the mclassdef_hierarchy
682 # The simpliest way is to attach it to collect_mclassdefs
683 for mclassdef
in mtype
.collect_mclassdefs
(mmodule
) do
684 res
.poset
.add_edge
(self, mclassdef
)
688 # The view of the class definition in `mclassdef_hierarchy`
689 var in_hierarchy
: nullable POSetElement[MClassDef] = null
691 # Is the definition the one that introduced `mclass`?
692 fun is_intro
: Bool do return isset mclass
._intro
and mclass
.intro
== self
694 # All properties introduced by the classdef
695 var intro_mproperties
= new Array[MProperty]
697 # All property definitions in the class (introductions and redefinitions)
698 var mpropdefs
= new Array[MPropDef]
701 # A global static type
703 # MType are global to the model; it means that a `MType` is not bound to a
704 # specific `MModule`.
705 # This characteristic helps the reasoning about static types in a program
706 # since a single `MType` object always denote the same type.
708 # However, because a `MType` is global, it does not really have properties
709 # nor have subtypes to a hierarchy since the property and the class hierarchy
710 # depends of a module.
711 # Moreover, virtual types an formal generic parameter types also depends on
712 # a receiver to have sense.
714 # Therefore, most method of the types require a module and an anchor.
715 # The module is used to know what are the classes and the specialization
717 # The anchor is used to know what is the bound of the virtual types and formal
718 # generic parameter types.
720 # MType are not directly usable to get properties. See the `anchor_to` method
721 # and the `MClassType` class.
723 # FIXME: the order of the parameters is not the best. We mus pick on from:
724 # * foo(mmodule, anchor, othertype)
725 # * foo(othertype, anchor, mmodule)
726 # * foo(anchor, mmodule, othertype)
727 # * foo(othertype, mmodule, anchor)
731 redef fun name
do return to_s
733 # Return true if `self` is an subtype of `sup`.
734 # The typing is done using the standard typing policy of Nit.
736 # REQUIRE: `anchor == null implies not self.need_anchor and not sup.need_anchor`
737 # REQUIRE: `anchor != null implies self.can_resolve_for(anchor, null, mmodule) and sup.can_resolve_for(anchor, null, mmodule)`
738 fun is_subtype
(mmodule
: MModule, anchor
: nullable MClassType, sup
: MType): Bool
741 if sub
== sup
then return true
743 #print "1.is {sub} a {sup}? ===="
745 if anchor
== null then
746 assert not sub
.need_anchor
747 assert not sup
.need_anchor
749 # First, resolve the formal types to the simplest equivalent forms in the receiver
750 assert sub
.can_resolve_for
(anchor
, null, mmodule
)
751 sub
= sub
.lookup_fixed
(mmodule
, anchor
)
752 assert sup
.can_resolve_for
(anchor
, null, mmodule
)
753 sup
= sup
.lookup_fixed
(mmodule
, anchor
)
756 # Does `sup` accept null or not?
757 # Discard the nullable marker if it exists
758 var sup_accept_null
= false
759 if sup
isa MNullableType then
760 sup_accept_null
= true
762 else if sup
isa MNotNullType then
764 else if sup
isa MNullType then
765 sup_accept_null
= true
768 # Can `sub` provide null or not?
769 # Thus we can match with `sup_accept_null`
770 # Also discard the nullable marker if it exists
771 var sub_reject_null
= false
772 if sub
isa MNullableType then
773 if not sup_accept_null
then return false
775 else if sub
isa MNotNullType then
776 sub_reject_null
= true
778 else if sub
isa MNullType then
779 return sup_accept_null
781 # Now the case of direct null and nullable is over.
783 # If `sub` is a formal type, then it is accepted if its bound is accepted
784 while sub
isa MFormalType do
785 #print "3.is {sub} a {sup}?"
787 # A unfixed formal type can only accept itself
788 if sub
== sup
then return true
790 assert anchor
!= null
791 sub
= sub
.lookup_bound
(mmodule
, anchor
)
792 if sub_reject_null
then sub
= sub
.as_notnull
794 #print "3.is {sub} a {sup}?"
796 # Manage the second layer of null/nullable
797 if sub
isa MNullableType then
798 if not sup_accept_null
and not sub_reject_null
then return false
800 else if sub
isa MNotNullType then
801 sub_reject_null
= true
803 else if sub
isa MNullType then
804 return sup_accept_null
807 #print "4.is {sub} a {sup}? <- no more resolution"
809 if sub
isa MBottomType then
813 assert sub
isa MClassType else print
"{sub} <? {sub}" # It is the only remaining type
815 # Handle sup-type when the sub-type is class-based (other cases must have be identified before).
816 if sup
isa MFormalType or sup
isa MNullType or sup
isa MBottomType then
817 # These types are not super-types of Class-based types.
821 assert sup
isa MClassType else print
"got {sup} {sub.inspect}" # It is the only remaining type
823 # Now both are MClassType, we need to dig
825 if sub
== sup
then return true
827 if anchor
== null then anchor
= sub
# UGLY: any anchor will work
828 var resolved_sub
= sub
.anchor_to
(mmodule
, anchor
)
829 var res
= resolved_sub
.collect_mclasses
(mmodule
).has
(sup
.mclass
)
830 if res
== false then return false
831 if not sup
isa MGenericType then return true
832 var sub2
= sub
.supertype_to
(mmodule
, anchor
, sup
.mclass
)
833 assert sub2
.mclass
== sup
.mclass
834 for i
in [0..sup
.mclass
.arity
[ do
835 var sub_arg
= sub2
.arguments
[i
]
836 var sup_arg
= sup
.arguments
[i
]
837 res
= sub_arg
.is_subtype
(mmodule
, anchor
, sup_arg
)
838 if res
== false then return false
843 # The base class type on which self is based
845 # This base type is used to get property (an internally to perform
846 # unsafe type comparison).
848 # Beware: some types (like null) are not based on a class thus this
851 # Basically, this function transform the virtual types and parameter
852 # types to their bounds.
857 # class B super A end
859 # class Y super X end
868 # Map[T,U] anchor_to H #-> Map[B,Y]
870 # Explanation of the example:
871 # In H, T is set to B, because "H super G[B]", and U is bound to Y,
872 # because "redef type U: Y". Therefore, Map[T, U] is bound to
875 # ENSURE: `not self.need_anchor implies result == self`
876 # ENSURE: `not result.need_anchor`
877 fun anchor_to
(mmodule
: MModule, anchor
: MClassType): MType
879 if not need_anchor
then return self
880 assert not anchor
.need_anchor
881 # Just resolve to the anchor and clear all the virtual types
882 var res
= self.resolve_for
(anchor
, null, mmodule
, true)
883 assert not res
.need_anchor
887 # Does `self` contain a virtual type or a formal generic parameter type?
888 # In order to remove those types, you usually want to use `anchor_to`.
889 fun need_anchor
: Bool do return true
891 # Return the supertype when adapted to a class.
893 # In Nit, for each super-class of a type, there is a equivalent super-type.
899 # class H[V] super G[V, Bool] end
901 # H[Int] supertype_to G #-> G[Int, Bool]
904 # REQUIRE: `super_mclass` is a super-class of `self`
905 # REQUIRE: `self.need_anchor implies anchor != null and self.can_resolve_for(anchor, null, mmodule)`
906 # ENSURE: `result.mclass = super_mclass`
907 fun supertype_to
(mmodule
: MModule, anchor
: nullable MClassType, super_mclass
: MClass): MClassType
909 if super_mclass
.arity
== 0 then return super_mclass
.mclass_type
910 if self isa MClassType and self.mclass
== super_mclass
then return self
912 if self.need_anchor
then
913 assert anchor
!= null
914 resolved_self
= self.anchor_to
(mmodule
, anchor
)
918 var supertypes
= resolved_self
.collect_mtypes
(mmodule
)
919 for supertype
in supertypes
do
920 if supertype
.mclass
== super_mclass
then
921 # FIXME: Here, we stop on the first goal. Should we check others and detect inconsistencies?
922 return supertype
.resolve_for
(self, anchor
, mmodule
, false)
928 # Replace formals generic types in self with resolved values in `mtype`
929 # If `cleanup_virtual` is true, then virtual types are also replaced
932 # This function returns self if `need_anchor` is false.
938 # class H[F] super G[F] end
942 # * Array[E].resolve_for(H[Int]) #-> Array[Int]
943 # * Array[E].resolve_for(G[Z], X[Int]) #-> Array[Z]
945 # Explanation of the example:
946 # * Array[E].need_anchor is true because there is a formal generic parameter type E
947 # * E makes sense for H[Int] because E is a formal parameter of G and H specialize G
948 # * Since "H[F] super G[F]", E is in fact F for H
949 # * More specifically, in H[Int], E is Int
950 # * So, in H[Int], Array[E] is Array[Int]
952 # This function is mainly used to inherit a signature.
953 # Because, unlike `anchor_to`, we do not want a full resolution of
954 # a type but only an adapted version of it.
960 # fun foo(e:E):E is abstract
962 # class B super A[Int] end
965 # The signature on foo is (e: E): E
966 # If we resolve the signature for B, we get (e:Int):Int
972 # fun foo(e:E):E is abstract
976 # fun bar do a.foo(x) # <- x is here
980 # The first question is: is foo available on `a`?
982 # The static type of a is `A[Array[F]]`, that is an open type.
983 # in order to find a method `foo`, whe must look at a resolved type.
985 # A[Array[F]].anchor_to(C[nullable Object]) #-> A[Array[nullable Object]]
987 # the method `foo` exists in `A[Array[nullable Object]]`, therefore `foo` exists for `a`.
989 # The next question is: what is the accepted types for `x`?
991 # the signature of `foo` is `foo(e:E)`, thus we must resolve the type E
993 # E.resolve_for(A[Array[F]],C[nullable Object]) #-> Array[F]
995 # The resolution can be done because `E` make sense for the class A (see `can_resolve_for`)
997 # FIXME: the parameter `cleanup_virtual` is just a bad idea, but having
998 # two function instead of one seems also to be a bad idea.
1000 # REQUIRE: `can_resolve_for(mtype, anchor, mmodule)`
1001 # ENSURE: `not self.need_anchor implies result == self`
1002 fun resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule, cleanup_virtual
: Bool): MType is abstract
1004 # Resolve formal type to its verbatim bound.
1005 # If the type is not formal, just return self
1007 # The result is returned exactly as declared in the "type" property (verbatim).
1008 # So it could be another formal type.
1010 # In case of conflicts or inconsistencies in the model, the method returns a `MBottomType`.
1011 fun lookup_bound
(mmodule
: MModule, resolved_receiver
: MType): MType do return self
1013 # Resolve the formal type to its simplest equivalent form.
1015 # Formal types are either free or fixed.
1016 # When it is fixed, it means that it is equivalent with a simpler type.
1017 # When a formal type is free, it means that it is only equivalent with itself.
1018 # This method return the most simple equivalent type of `self`.
1020 # This method is mainly used for subtype test in order to sanely compare fixed.
1022 # By default, return self.
1023 # See the redefinitions for specific behavior in each kind of type.
1025 # In case of conflicts or inconsistencies in the model, the method returns a `MBottomType`.
1026 fun lookup_fixed
(mmodule
: MModule, resolved_receiver
: MType): MType do return self
1028 # Can the type be resolved?
1030 # In order to resolve open types, the formal types must make sence.
1040 # E.can_resolve_for(A[Int]) #-> true, E make sense in A
1042 # E.can_resolve_for(B[Int]) #-> false, E does not make sense in B
1044 # B[E].can_resolve_for(A[F], B[Object]) #-> true,
1045 # # B[E] is a red hearing only the E is important,
1046 # # E make sense in A
1049 # REQUIRE: `anchor != null implies not anchor.need_anchor`
1050 # REQUIRE: `mtype.need_anchor implies anchor != null and mtype.can_resolve_for(anchor, null, mmodule)`
1051 # ENSURE: `not self.need_anchor implies result == true`
1052 fun can_resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule): Bool is abstract
1054 # Return the nullable version of the type
1055 # If the type is already nullable then self is returned
1056 fun as_nullable
: MType
1058 var res
= self.as_nullable_cache
1059 if res
!= null then return res
1060 res
= new MNullableType(self)
1061 self.as_nullable_cache
= res
1065 # Remove the base type of a decorated (proxy) type.
1066 # Is the type is not decorated, then self is returned.
1068 # Most of the time it is used to return the not nullable version of a nullable type.
1069 # In this case, this just remove the `nullable` notation, but the result can still contains null.
1070 # For instance if `self isa MNullType` or self is a formal type bounded by a nullable type.
1071 # If you really want to exclude the `null` value, then use `as_notnull`
1072 fun undecorate
: MType
1077 # Returns the not null version of the type.
1078 # That is `self` minus the `null` value.
1080 # For most types, this return `self`.
1081 # For formal types, this returns a special `MNotNullType`
1082 fun as_notnull
: MType do return self
1084 private var as_nullable_cache
: nullable MType = null
1087 # The depth of the type seen as a tree.
1094 # Formal types have a depth of 1.
1100 # The length of the type seen as a tree.
1107 # Formal types have a length of 1.
1113 # Compute all the classdefs inherited/imported.
1114 # The returned set contains:
1115 # * the class definitions from `mmodule` and its imported modules
1116 # * the class definitions of this type and its super-types
1118 # This function is used mainly internally.
1120 # REQUIRE: `not self.need_anchor`
1121 fun collect_mclassdefs
(mmodule
: MModule): Set[MClassDef] is abstract
1123 # Compute all the super-classes.
1124 # This function is used mainly internally.
1126 # REQUIRE: `not self.need_anchor`
1127 fun collect_mclasses
(mmodule
: MModule): Set[MClass] is abstract
1129 # Compute all the declared super-types.
1130 # Super-types are returned as declared in the classdefs (verbatim).
1131 # This function is used mainly internally.
1133 # REQUIRE: `not self.need_anchor`
1134 fun collect_mtypes
(mmodule
: MModule): Set[MClassType] is abstract
1136 # Is the property in self for a given module
1137 # This method does not filter visibility or whatever
1139 # REQUIRE: `not self.need_anchor`
1140 fun has_mproperty
(mmodule
: MModule, mproperty
: MProperty): Bool
1142 assert not self.need_anchor
1143 return self.collect_mclassdefs
(mmodule
).has
(mproperty
.intro_mclassdef
)
1147 # A type based on a class.
1149 # `MClassType` have properties (see `has_mproperty`).
1153 # The associated class
1156 redef fun model
do return self.mclass
.intro_mmodule
.model
1158 # TODO: private init because strongly bounded to its mclass. see `mclass.mclass_type`
1160 # The formal arguments of the type
1161 # ENSURE: `result.length == self.mclass.arity`
1162 var arguments
= new Array[MType]
1164 redef fun to_s
do return mclass
.to_s
1166 redef fun full_name
do return mclass
.full_name
1168 redef fun c_name
do return mclass
.c_name
1170 redef fun need_anchor
do return false
1172 redef fun anchor_to
(mmodule
: MModule, anchor
: MClassType): MClassType
1174 return super.as(MClassType)
1177 redef fun resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule, cleanup_virtual
: Bool): MClassType do return self
1179 redef fun can_resolve_for
(mtype
, anchor
, mmodule
) do return true
1181 redef fun collect_mclassdefs
(mmodule
)
1183 assert not self.need_anchor
1184 var cache
= self.collect_mclassdefs_cache
1185 if not cache
.has_key
(mmodule
) then
1186 self.collect_things
(mmodule
)
1188 return cache
[mmodule
]
1191 redef fun collect_mclasses
(mmodule
)
1193 if collect_mclasses_last_module
== mmodule
then return collect_mclasses_last_module_cache
1194 assert not self.need_anchor
1195 var cache
= self.collect_mclasses_cache
1196 if not cache
.has_key
(mmodule
) then
1197 self.collect_things
(mmodule
)
1199 var res
= cache
[mmodule
]
1200 collect_mclasses_last_module
= mmodule
1201 collect_mclasses_last_module_cache
= res
1205 private var collect_mclasses_last_module
: nullable MModule = null
1206 private var collect_mclasses_last_module_cache
: Set[MClass] is noinit
1208 redef fun collect_mtypes
(mmodule
)
1210 assert not self.need_anchor
1211 var cache
= self.collect_mtypes_cache
1212 if not cache
.has_key
(mmodule
) then
1213 self.collect_things
(mmodule
)
1215 return cache
[mmodule
]
1218 # common implementation for `collect_mclassdefs`, `collect_mclasses`, and `collect_mtypes`.
1219 private fun collect_things
(mmodule
: MModule)
1221 var res
= new HashSet[MClassDef]
1222 var seen
= new HashSet[MClass]
1223 var types
= new HashSet[MClassType]
1224 seen
.add
(self.mclass
)
1225 var todo
= [self.mclass
]
1226 while not todo
.is_empty
do
1227 var mclass
= todo
.pop
1228 #print "process {mclass}"
1229 for mclassdef
in mclass
.mclassdefs
do
1230 if not mmodule
.in_importation
<= mclassdef
.mmodule
then continue
1231 #print " process {mclassdef}"
1233 for supertype
in mclassdef
.supertypes
do
1234 types
.add
(supertype
)
1235 var superclass
= supertype
.mclass
1236 if seen
.has
(superclass
) then continue
1237 #print " add {superclass}"
1238 seen
.add
(superclass
)
1239 todo
.add
(superclass
)
1243 collect_mclassdefs_cache
[mmodule
] = res
1244 collect_mclasses_cache
[mmodule
] = seen
1245 collect_mtypes_cache
[mmodule
] = types
1248 private var collect_mclassdefs_cache
= new HashMap[MModule, Set[MClassDef]]
1249 private var collect_mclasses_cache
= new HashMap[MModule, Set[MClass]]
1250 private var collect_mtypes_cache
= new HashMap[MModule, Set[MClassType]]
1254 # A type based on a generic class.
1255 # A generic type a just a class with additional formal generic arguments.
1261 # TODO: private init because strongly bounded to its mclass. see `mclass.get_mtype`
1265 assert self.mclass
.arity
== arguments
.length
1267 self.need_anchor
= false
1268 for t
in arguments
do
1269 if t
.need_anchor
then
1270 self.need_anchor
= true
1275 self.to_s
= "{mclass}[{arguments.join(", ")}]"
1278 # The short-name of the class, then the full-name of each type arguments within brackets.
1279 # Example: `"Map[String, List[Int]]"`
1280 redef var to_s
: String is noinit
1282 # The full-name of the class, then the full-name of each type arguments within brackets.
1283 # Example: `"core::Map[core::String, core::List[core::Int]]"`
1284 redef var full_name
is lazy
do
1285 var args
= new Array[String]
1286 for t
in arguments
do
1287 args
.add t
.full_name
1289 return "{mclass.full_name}[{args.join(", ")}]"
1292 redef var c_name
is lazy
do
1293 var res
= mclass
.c_name
1294 # Note: because the arity is known, a prefix notation is enough
1295 for t
in arguments
do
1302 redef var need_anchor
: Bool is noinit
1304 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1306 if not need_anchor
then return self
1307 assert can_resolve_for
(mtype
, anchor
, mmodule
)
1308 var types
= new Array[MType]
1309 for t
in arguments
do
1310 types
.add
(t
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
))
1312 return mclass
.get_mtype
(types
)
1315 redef fun can_resolve_for
(mtype
, anchor
, mmodule
)
1317 if not need_anchor
then return true
1318 for t
in arguments
do
1319 if not t
.can_resolve_for
(mtype
, anchor
, mmodule
) then return false
1328 for a
in self.arguments
do
1330 if d
> dmax
then dmax
= d
1338 for a
in self.arguments
do
1345 # A formal type (either virtual of parametric).
1347 # The main issue with formal types is that they offer very little information on their own
1348 # and need a context (anchor and mmodule) to be useful.
1349 abstract class MFormalType
1352 redef var as_notnull
= new MNotNullType(self) is lazy
1355 # A virtual formal type.
1359 # The property associated with the type.
1360 # Its the definitions of this property that determine the bound or the virtual type.
1361 var mproperty
: MVirtualTypeProp
1363 redef fun model
do return self.mproperty
.intro_mclassdef
.mmodule
.model
1365 redef fun lookup_bound
(mmodule
: MModule, resolved_receiver
: MType): MType
1367 return lookup_single_definition
(mmodule
, resolved_receiver
).bound
or else new MBottomType(model
)
1370 private fun lookup_single_definition
(mmodule
: MModule, resolved_receiver
: MType): MVirtualTypeDef
1372 assert not resolved_receiver
.need_anchor
1373 var props
= self.mproperty
.lookup_definitions
(mmodule
, resolved_receiver
)
1374 if props
.is_empty
then
1376 else if props
.length
== 1 then
1379 var types
= new ArraySet[MType]
1380 var res
= props
.first
1382 types
.add
(p
.bound
.as(not null))
1383 if not res
.is_fixed
then res
= p
1385 if types
.length
== 1 then
1391 # A VT is fixed when:
1392 # * the VT is (re-)defined with the annotation `is fixed`
1393 # * the VT is (indirectly) bound to an enum class (see `enum_kind`) since there is no subtype possible
1394 # * the receiver is an enum class since there is no subtype possible
1395 redef fun lookup_fixed
(mmodule
: MModule, resolved_receiver
: MType): MType
1397 assert not resolved_receiver
.need_anchor
1398 resolved_receiver
= resolved_receiver
.undecorate
1399 assert resolved_receiver
isa MClassType # It is the only remaining type
1401 var prop
= lookup_single_definition
(mmodule
, resolved_receiver
)
1402 var res
= prop
.bound
1403 if res
== null then return new MBottomType(model
)
1405 # Recursively lookup the fixed result
1406 res
= res
.lookup_fixed
(mmodule
, resolved_receiver
)
1408 # 1. For a fixed VT, return the resolved bound
1409 if prop
.is_fixed
then return res
1411 # 2. For a enum boud, return the bound
1412 if res
isa MClassType and res
.mclass
.kind
== enum_kind
then return res
1414 # 3. for a enum receiver return the bound
1415 if resolved_receiver
.mclass
.kind
== enum_kind
then return res
1420 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1422 if not cleanup_virtual
then return self
1423 assert can_resolve_for
(mtype
, anchor
, mmodule
)
1424 # self is a virtual type declared (or inherited) in mtype
1425 # The point of the function it to get the bound of the virtual type that make sense for mtype
1426 # But because mtype is maybe a virtual/formal type, we need to get a real receiver first
1427 #print "{class_name}: {self}/{mtype}/{anchor}?"
1428 var resolved_receiver
1429 if mtype
.need_anchor
then
1430 assert anchor
!= null
1431 resolved_receiver
= mtype
.resolve_for
(anchor
, null, mmodule
, true)
1433 resolved_receiver
= mtype
1435 # Now, we can get the bound
1436 var verbatim_bound
= lookup_bound
(mmodule
, resolved_receiver
)
1437 # The bound is exactly as declared in the "type" property, so we must resolve it again
1438 var res
= verbatim_bound
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1443 redef fun can_resolve_for
(mtype
, anchor
, mmodule
)
1445 if mtype
.need_anchor
then
1446 assert anchor
!= null
1447 mtype
= mtype
.anchor_to
(mmodule
, anchor
)
1449 return mtype
.has_mproperty
(mmodule
, mproperty
)
1452 redef fun to_s
do return self.mproperty
.to_s
1454 redef fun full_name
do return self.mproperty
.full_name
1456 redef fun c_name
do return self.mproperty
.c_name
1459 # The type associated to a formal parameter generic type of a class
1461 # Each parameter type is associated to a specific class.
1462 # It means that all refinements of a same class "share" the parameter type,
1463 # but that a generic subclass has its own parameter types.
1465 # However, in the sense of the meta-model, a parameter type of a class is
1466 # a valid type in a subclass. The "in the sense of the meta-model" is
1467 # important because, in the Nit language, the programmer cannot refers
1468 # directly to the parameter types of the super-classes.
1473 # fun e: E is abstract
1479 # In the class definition B[F], `F` is a valid type but `E` is not.
1480 # However, `self.e` is a valid method call, and the signature of `e` is
1483 # Note that parameter types are shared among class refinements.
1484 # Therefore parameter only have an internal name (see `to_s` for details).
1485 class MParameterType
1488 # The generic class where the parameter belong
1491 redef fun model
do return self.mclass
.intro_mmodule
.model
1493 # The position of the parameter (0 for the first parameter)
1494 # FIXME: is `position` a better name?
1499 redef fun to_s
do return name
1501 redef var full_name
is lazy
do return "{mclass.full_name}::{name}"
1503 redef var c_name
is lazy
do return mclass
.c_name
+ "__" + "#{name}".to_cmangle
1505 redef fun lookup_bound
(mmodule
: MModule, resolved_receiver
: MType): MType
1507 assert not resolved_receiver
.need_anchor
1508 resolved_receiver
= resolved_receiver
.undecorate
1509 assert resolved_receiver
isa MClassType # It is the only remaining type
1510 var goalclass
= self.mclass
1511 if resolved_receiver
.mclass
== goalclass
then
1512 return resolved_receiver
.arguments
[self.rank
]
1514 var supertypes
= resolved_receiver
.collect_mtypes
(mmodule
)
1515 for t
in supertypes
do
1516 if t
.mclass
== goalclass
then
1517 # Yeah! c specialize goalclass with a "super `t'". So the question is what is the argument of f
1518 # FIXME: Here, we stop on the first goal. Should we check others and detect inconsistencies?
1519 var res
= t
.arguments
[self.rank
]
1526 # A PT is fixed when:
1527 # * Its bound is a enum class (see `enum_kind`).
1528 # The PT is just useless, but it is still a case.
1529 # * More usually, the `resolved_receiver` is a subclass of `self.mclass`,
1530 # so it is necessarily fixed in a `super` clause, either with a normal type
1531 # or with another PT.
1532 # See `resolve_for` for examples about related issues.
1533 redef fun lookup_fixed
(mmodule
: MModule, resolved_receiver
: MType): MType
1535 assert not resolved_receiver
.need_anchor
1536 resolved_receiver
= resolved_receiver
.undecorate
1537 assert resolved_receiver
isa MClassType # It is the only remaining type
1538 var res
= self.resolve_for
(resolved_receiver
.mclass
.mclass_type
, resolved_receiver
, mmodule
, false)
1542 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1544 assert can_resolve_for
(mtype
, anchor
, mmodule
)
1545 #print "{class_name}: {self}/{mtype}/{anchor}?"
1547 if mtype
isa MGenericType and mtype
.mclass
== self.mclass
then
1548 var res
= mtype
.arguments
[self.rank
]
1549 if anchor
!= null and res
.need_anchor
then
1550 # Maybe the result can be resolved more if are bound to a final class
1551 var r2
= res
.anchor_to
(mmodule
, anchor
)
1552 if r2
isa MClassType and r2
.mclass
.kind
== enum_kind
then return r2
1557 # self is a parameter type of mtype (or of a super-class of mtype)
1558 # The point of the function it to get the bound of the virtual type that make sense for mtype
1559 # But because mtype is maybe a virtual/formal type, we need to get a real receiver first
1560 # FIXME: What happens here is far from clear. Thus this part must be validated and clarified
1561 var resolved_receiver
1562 if mtype
.need_anchor
then
1563 assert anchor
!= null
1564 resolved_receiver
= mtype
.resolve_for
(anchor
.mclass
.mclass_type
, anchor
, mmodule
, true)
1566 resolved_receiver
= mtype
1568 if resolved_receiver
isa MNullableType then resolved_receiver
= resolved_receiver
.mtype
1569 if resolved_receiver
isa MParameterType then
1570 assert anchor
!= null
1571 assert resolved_receiver
.mclass
== anchor
.mclass
1572 resolved_receiver
= anchor
.arguments
[resolved_receiver
.rank
]
1573 if resolved_receiver
isa MNullableType then resolved_receiver
= resolved_receiver
.mtype
1575 assert resolved_receiver
isa MClassType # It is the only remaining type
1577 # Eh! The parameter is in the current class.
1578 # So we return the corresponding argument, no mater what!
1579 if resolved_receiver
.mclass
== self.mclass
then
1580 var res
= resolved_receiver
.arguments
[self.rank
]
1581 #print "{class_name}: {self}/{mtype}/{anchor} -> direct {res}"
1585 if resolved_receiver
.need_anchor
then
1586 assert anchor
!= null
1587 resolved_receiver
= resolved_receiver
.resolve_for
(anchor
, null, mmodule
, false)
1589 # Now, we can get the bound
1590 var verbatim_bound
= lookup_bound
(mmodule
, resolved_receiver
)
1591 # The bound is exactly as declared in the "type" property, so we must resolve it again
1592 var res
= verbatim_bound
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1594 #print "{class_name}: {self}/{mtype}/{anchor} -> indirect {res}"
1599 redef fun can_resolve_for
(mtype
, anchor
, mmodule
)
1601 if mtype
.need_anchor
then
1602 assert anchor
!= null
1603 mtype
= mtype
.anchor_to
(mmodule
, anchor
)
1605 return mtype
.collect_mclassdefs
(mmodule
).has
(mclass
.intro
)
1609 # A type that decorates another type.
1611 # The point of this class is to provide a common implementation of sevices that just forward to the original type.
1612 # Specific decorator are expected to redefine (or to extend) the default implementation as this suit them.
1613 abstract class MProxyType
1618 redef fun model
do return self.mtype
.model
1619 redef fun need_anchor
do return mtype
.need_anchor
1620 redef fun as_nullable
do return mtype
.as_nullable
1621 redef fun as_notnull
do return mtype
.as_notnull
1622 redef fun undecorate
do return mtype
.undecorate
1623 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1625 var res
= self.mtype
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1629 redef fun can_resolve_for
(mtype
, anchor
, mmodule
)
1631 return self.mtype
.can_resolve_for
(mtype
, anchor
, mmodule
)
1634 redef fun lookup_fixed
(mmodule
, resolved_receiver
)
1636 var t
= mtype
.lookup_fixed
(mmodule
, resolved_receiver
)
1640 redef fun depth
do return self.mtype
.depth
1642 redef fun length
do return self.mtype
.length
1644 redef fun collect_mclassdefs
(mmodule
)
1646 assert not self.need_anchor
1647 return self.mtype
.collect_mclassdefs
(mmodule
)
1650 redef fun collect_mclasses
(mmodule
)
1652 assert not self.need_anchor
1653 return self.mtype
.collect_mclasses
(mmodule
)
1656 redef fun collect_mtypes
(mmodule
)
1658 assert not self.need_anchor
1659 return self.mtype
.collect_mtypes
(mmodule
)
1663 # A type prefixed with "nullable"
1669 self.to_s
= "nullable {mtype}"
1672 redef var to_s
: String is noinit
1674 redef var full_name
is lazy
do return "nullable {mtype.full_name}"
1676 redef var c_name
is lazy
do return "nullable__{mtype.c_name}"
1678 redef fun as_nullable
do return self
1679 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1682 return res
.as_nullable
1685 # Efficiently returns `mtype.lookup_fixed(mmodule, resolved_receiver).as_nullable`
1686 redef fun lookup_fixed
(mmodule
, resolved_receiver
)
1689 if t
== mtype
then return self
1690 return t
.as_nullable
1694 # A non-null version of a formal type.
1696 # When a formal type in bounded to a nullable type, this is the type of the not null version of it.
1700 redef fun to_s
do return "not null {mtype}"
1701 redef var full_name
is lazy
do return "not null {mtype.full_name}"
1702 redef var c_name
is lazy
do return "notnull__{mtype.c_name}"
1704 redef fun as_notnull
do return self
1706 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1709 return res
.as_notnull
1712 # Efficiently returns `mtype.lookup_fixed(mmodule, resolved_receiver).as_notnull`
1713 redef fun lookup_fixed
(mmodule
, resolved_receiver
)
1716 if t
== mtype
then return self
1721 # The type of the only value null
1723 # The is only one null type per model, see `MModel::null_type`.
1726 redef var model
: Model
1727 redef fun to_s
do return "null"
1728 redef fun full_name
do return "null"
1729 redef fun c_name
do return "null"
1730 redef fun as_nullable
do return self
1732 redef var as_notnull
= new MBottomType(model
) is lazy
1733 redef fun need_anchor
do return false
1734 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
) do return self
1735 redef fun can_resolve_for
(mtype
, anchor
, mmodule
) do return true
1737 redef fun collect_mclassdefs
(mmodule
) do return new HashSet[MClassDef]
1739 redef fun collect_mclasses
(mmodule
) do return new HashSet[MClass]
1741 redef fun collect_mtypes
(mmodule
) do return new HashSet[MClassType]
1744 # The special universal most specific type.
1746 # This type is intended to be only used internally for type computation or analysis and should not be exposed to the user.
1747 # The bottom type can de used to denote things that are absurd, dead, or the absence of knowledge.
1749 # Semantically it is the singleton `null.as_notnull`.
1752 redef var model
: Model
1753 redef fun to_s
do return "bottom"
1754 redef fun full_name
do return "bottom"
1755 redef fun c_name
do return "bottom"
1756 redef fun as_nullable
do return model
.null_type
1757 redef fun as_notnull
do return self
1758 redef fun need_anchor
do return false
1759 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
) do return self
1760 redef fun can_resolve_for
(mtype
, anchor
, mmodule
) do return true
1762 redef fun collect_mclassdefs
(mmodule
) do return new HashSet[MClassDef]
1764 redef fun collect_mclasses
(mmodule
) do return new HashSet[MClass]
1766 redef fun collect_mtypes
(mmodule
) do return new HashSet[MClassType]
1769 # A signature of a method
1773 # The each parameter (in order)
1774 var mparameters
: Array[MParameter]
1776 # Returns a parameter named `name`, if any.
1777 fun mparameter_by_name
(name
: String): nullable MParameter
1779 for p
in mparameters
do
1780 if p
.name
== name
then return p
1785 # The return type (null for a procedure)
1786 var return_mtype
: nullable MType
1791 var t
= self.return_mtype
1792 if t
!= null then dmax
= t
.depth
1793 for p
in mparameters
do
1794 var d
= p
.mtype
.depth
1795 if d
> dmax
then dmax
= d
1803 var t
= self.return_mtype
1804 if t
!= null then res
+= t
.length
1805 for p
in mparameters
do
1806 res
+= p
.mtype
.length
1811 # REQUIRE: 1 <= mparameters.count p -> p.is_vararg
1814 var vararg_rank
= -1
1815 for i
in [0..mparameters
.length
[ do
1816 var parameter
= mparameters
[i
]
1817 if parameter
.is_vararg
then
1818 if vararg_rank
>= 0 then
1819 # If there is more than one vararg,
1820 # consider that additional arguments cannot be mapped.
1827 self.vararg_rank
= vararg_rank
1830 # The rank of the main ellipsis (`...`) for vararg (starting from 0).
1831 # value is -1 if there is no vararg.
1832 # Example: for "(a: Int, b: Bool..., c: Char)" #-> vararg_rank=1
1834 # From a model POV, a signature can contain more than one vararg parameter,
1835 # the `vararg_rank` just indicates the one that will receive the additional arguments.
1836 # However, currently, if there is more that one vararg parameter, no one will be the main one,
1837 # and additional arguments will be refused.
1838 var vararg_rank
: Int is noinit
1840 # The number of parameters
1841 fun arity
: Int do return mparameters
.length
1845 var b
= new FlatBuffer
1846 if not mparameters
.is_empty
then
1848 for i
in [0..mparameters
.length
[ do
1849 var mparameter
= mparameters
[i
]
1850 if i
> 0 then b
.append
(", ")
1851 b
.append
(mparameter
.name
)
1853 b
.append
(mparameter
.mtype
.to_s
)
1854 if mparameter
.is_vararg
then
1860 var ret
= self.return_mtype
1868 redef fun resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule, cleanup_virtual
: Bool): MSignature
1870 var params
= new Array[MParameter]
1871 for p
in self.mparameters
do
1872 params
.add
(p
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
))
1874 var ret
= self.return_mtype
1876 ret
= ret
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1878 var res
= new MSignature(params
, ret
)
1883 # A parameter in a signature
1887 # The name of the parameter
1888 redef var name
: String
1890 # The static type of the parameter
1893 # Is the parameter a vararg?
1899 return "{name}: {mtype}..."
1901 return "{name}: {mtype}"
1905 # Returns a new parameter with the `mtype` resolved.
1906 # See `MType::resolve_for` for details.
1907 fun resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule, cleanup_virtual
: Bool): MParameter
1909 if not self.mtype
.need_anchor
then return self
1910 var newtype
= self.mtype
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1911 var res
= new MParameter(self.name
, newtype
, self.is_vararg
)
1915 redef fun model
do return mtype
.model
1918 # A service (global property) that generalize method, attribute, etc.
1920 # `MProperty` are global to the model; it means that a `MProperty` is not bound
1921 # to a specific `MModule` nor a specific `MClass`.
1923 # A MProperty gather definitions (see `mpropdefs`) ; one for the introduction
1924 # and the other in subclasses and in refinements.
1926 # A `MProperty` is used to denotes services in polymorphic way (ie. independent
1927 # of any dynamic type).
1928 # For instance, a call site "x.foo" is associated to a `MProperty`.
1929 abstract class MProperty
1932 # The associated MPropDef subclass.
1933 # The two specialization hierarchy are symmetric.
1934 type MPROPDEF: MPropDef
1936 # The classdef that introduce the property
1937 # While a property is not bound to a specific module, or class,
1938 # the introducing mclassdef is used for naming and visibility
1939 var intro_mclassdef
: MClassDef
1941 # The (short) name of the property
1942 redef var name
: String
1944 # The canonical name of the property.
1946 # It is the short-`name` prefixed by the short-name of the class and the full-name of the module.
1947 # Example: "my_package::my_module::MyClass::my_method"
1948 redef var full_name
is lazy
do
1949 return "{intro_mclassdef.mmodule.namespace_for(visibility)}::{intro_mclassdef.mclass.name}::{name}"
1952 redef var c_name
is lazy
do
1953 # FIXME use `namespace_for`
1954 return "{intro_mclassdef.mmodule.c_name}__{intro_mclassdef.mclass.name.to_cmangle}__{name.to_cmangle}"
1957 # The visibility of the property
1958 var visibility
: MVisibility
1960 # Is the property usable as an initializer?
1961 var is_autoinit
= false is writable
1965 intro_mclassdef
.intro_mproperties
.add
(self)
1966 var model
= intro_mclassdef
.mmodule
.model
1967 model
.mproperties_by_name
.add_one
(name
, self)
1968 model
.mproperties
.add
(self)
1971 # All definitions of the property.
1972 # The first is the introduction,
1973 # The other are redefinitions (in refinements and in subclasses)
1974 var mpropdefs
= new Array[MPROPDEF]
1976 # The definition that introduces the property.
1978 # Warning: such a definition may not exist in the early life of the object.
1979 # In this case, the method will abort.
1980 var intro
: MPROPDEF is noinit
1982 redef fun model
do return intro
.model
1985 redef fun to_s
do return name
1987 # Return the most specific property definitions defined or inherited by a type.
1988 # The selection knows that refinement is stronger than specialization;
1989 # however, in case of conflict more than one property are returned.
1990 # If mtype does not know mproperty then an empty array is returned.
1992 # If you want the really most specific property, then look at `lookup_first_definition`
1994 # REQUIRE: `not mtype.need_anchor` to simplify the API (no `anchor` parameter)
1995 # ENSURE: `not mtype.has_mproperty(mmodule, self) == result.is_empty`
1996 fun lookup_definitions
(mmodule
: MModule, mtype
: MType): Array[MPROPDEF]
1998 assert not mtype
.need_anchor
1999 mtype
= mtype
.undecorate
2001 var cache
= self.lookup_definitions_cache
[mmodule
, mtype
]
2002 if cache
!= null then return cache
2004 #print "select prop {mproperty} for {mtype} in {self}"
2005 # First, select all candidates
2006 var candidates
= new Array[MPROPDEF]
2007 for mpropdef
in self.mpropdefs
do
2008 # If the definition is not imported by the module, then skip
2009 if not mmodule
.in_importation
<= mpropdef
.mclassdef
.mmodule
then continue
2010 # If the definition is not inherited by the type, then skip
2011 if not mtype
.is_subtype
(mmodule
, null, mpropdef
.mclassdef
.bound_mtype
) then continue
2013 candidates
.add
(mpropdef
)
2015 # Fast track for only one candidate
2016 if candidates
.length
<= 1 then
2017 self.lookup_definitions_cache
[mmodule
, mtype
] = candidates
2021 # Second, filter the most specific ones
2022 return select_most_specific
(mmodule
, candidates
)
2025 private var lookup_definitions_cache
= new HashMap2[MModule, MType, Array[MPROPDEF]]
2027 # Return the most specific property definitions inherited by a type.
2028 # The selection knows that refinement is stronger than specialization;
2029 # however, in case of conflict more than one property are returned.
2030 # If mtype does not know mproperty then an empty array is returned.
2032 # If you want the really most specific property, then look at `lookup_next_definition`
2034 # REQUIRE: `not mtype.need_anchor` to simplify the API (no `anchor` parameter)
2035 # ENSURE: `not mtype.has_mproperty(mmodule, self) implies result.is_empty`
2036 fun lookup_super_definitions
(mmodule
: MModule, mtype
: MType): Array[MPROPDEF]
2038 assert not mtype
.need_anchor
2039 mtype
= mtype
.undecorate
2041 # First, select all candidates
2042 var candidates
= new Array[MPROPDEF]
2043 for mpropdef
in self.mpropdefs
do
2044 # If the definition is not imported by the module, then skip
2045 if not mmodule
.in_importation
<= mpropdef
.mclassdef
.mmodule
then continue
2046 # If the definition is not inherited by the type, then skip
2047 if not mtype
.is_subtype
(mmodule
, null, mpropdef
.mclassdef
.bound_mtype
) then continue
2048 # If the definition is defined by the type, then skip (we want the super, so e skip the current)
2049 if mtype
== mpropdef
.mclassdef
.bound_mtype
and mmodule
== mpropdef
.mclassdef
.mmodule
then continue
2051 candidates
.add
(mpropdef
)
2053 # Fast track for only one candidate
2054 if candidates
.length
<= 1 then return candidates
2056 # Second, filter the most specific ones
2057 return select_most_specific
(mmodule
, candidates
)
2060 # Return an array containing olny the most specific property definitions
2061 # This is an helper function for `lookup_definitions` and `lookup_super_definitions`
2062 private fun select_most_specific
(mmodule
: MModule, candidates
: Array[MPROPDEF]): Array[MPROPDEF]
2064 var res
= new Array[MPROPDEF]
2065 for pd1
in candidates
do
2066 var cd1
= pd1
.mclassdef
2069 for pd2
in candidates
do
2070 if pd2
== pd1
then continue # do not compare with self!
2071 var cd2
= pd2
.mclassdef
2073 if c2
.mclass_type
== c1
.mclass_type
then
2074 if cd2
.mmodule
.in_importation
< cd1
.mmodule
then
2075 # cd2 refines cd1; therefore we skip pd1
2079 else if cd2
.bound_mtype
.is_subtype
(mmodule
, null, cd1
.bound_mtype
) and cd2
.bound_mtype
!= cd1
.bound_mtype
then
2080 # cd2 < cd1; therefore we skip pd1
2089 if res
.is_empty
then
2090 print
"All lost! {candidates.join(", ")}"
2091 # FIXME: should be abort!
2096 # Return the most specific definition in the linearization of `mtype`.
2098 # If you want to know the next properties in the linearization,
2099 # look at `MPropDef::lookup_next_definition`.
2101 # FIXME: the linearization is still unspecified
2103 # REQUIRE: `not mtype.need_anchor` to simplify the API (no `anchor` parameter)
2104 # REQUIRE: `mtype.has_mproperty(mmodule, self)`
2105 fun lookup_first_definition
(mmodule
: MModule, mtype
: MType): MPROPDEF
2107 return lookup_all_definitions
(mmodule
, mtype
).first
2110 # Return all definitions in a linearization order
2111 # Most specific first, most general last
2113 # REQUIRE: `not mtype.need_anchor` to simplify the API (no `anchor` parameter)
2114 # REQUIRE: `mtype.has_mproperty(mmodule, self)`
2115 fun lookup_all_definitions
(mmodule
: MModule, mtype
: MType): Array[MPROPDEF]
2117 mtype
= mtype
.undecorate
2119 var cache
= self.lookup_all_definitions_cache
[mmodule
, mtype
]
2120 if cache
!= null then return cache
2122 assert not mtype
.need_anchor
2123 assert mtype
.has_mproperty
(mmodule
, self)
2125 #print "select prop {mproperty} for {mtype} in {self}"
2126 # First, select all candidates
2127 var candidates
= new Array[MPROPDEF]
2128 for mpropdef
in self.mpropdefs
do
2129 # If the definition is not imported by the module, then skip
2130 if not mmodule
.in_importation
<= mpropdef
.mclassdef
.mmodule
then continue
2131 # If the definition is not inherited by the type, then skip
2132 if not mtype
.is_subtype
(mmodule
, null, mpropdef
.mclassdef
.bound_mtype
) then continue
2134 candidates
.add
(mpropdef
)
2136 # Fast track for only one candidate
2137 if candidates
.length
<= 1 then
2138 self.lookup_all_definitions_cache
[mmodule
, mtype
] = candidates
2142 mmodule
.linearize_mpropdefs
(candidates
)
2143 candidates
= candidates
.reversed
2144 self.lookup_all_definitions_cache
[mmodule
, mtype
] = candidates
2148 private var lookup_all_definitions_cache
= new HashMap2[MModule, MType, Array[MPROPDEF]]
2155 redef type MPROPDEF: MMethodDef
2157 # Is the property defined at the top_level of the module?
2158 # Currently such a property are stored in `Object`
2159 var is_toplevel
: Bool = false is writable
2161 # Is the property a constructor?
2162 # Warning, this property can be inherited by subclasses with or without being a constructor
2163 # therefore, you should use `is_init_for` the verify if the property is a legal constructor for a given class
2164 var is_init
: Bool = false is writable
2166 # The constructor is a (the) root init with empty signature but a set of initializers
2167 var is_root_init
: Bool = false is writable
2169 # Is the property a 'new' constructor?
2170 var is_new
: Bool = false is writable
2172 # Is the property a legal constructor for a given class?
2173 # As usual, visibility is not considered.
2174 # FIXME not implemented
2175 fun is_init_for
(mclass
: MClass): Bool
2180 # A specific method that is safe to call on null.
2181 # Currently, only `==`, `!=` and `is_same_instance` are safe
2182 fun is_null_safe
: Bool do return name
== "==" or name
== "!=" or name
== "is_same_instance"
2185 # A global attribute
2189 redef type MPROPDEF: MAttributeDef
2193 # A global virtual type
2194 class MVirtualTypeProp
2197 redef type MPROPDEF: MVirtualTypeDef
2199 # The formal type associated to the virtual type property
2200 var mvirtualtype
= new MVirtualType(self)
2203 # A definition of a property (local property)
2205 # Unlike `MProperty`, a `MPropDef` is a local definition that belong to a
2206 # specific class definition (which belong to a specific module)
2207 abstract class MPropDef
2210 # The associated `MProperty` subclass.
2211 # the two specialization hierarchy are symmetric
2212 type MPROPERTY: MProperty
2215 type MPROPDEF: MPropDef
2217 # The class definition where the property definition is
2218 var mclassdef
: MClassDef
2220 # The associated global property
2221 var mproperty
: MPROPERTY
2223 # The origin of the definition
2224 var location
: Location
2228 mclassdef
.mpropdefs
.add
(self)
2229 mproperty
.mpropdefs
.add
(self)
2230 if mproperty
.intro_mclassdef
== mclassdef
then
2231 assert not isset mproperty
._intro
2232 mproperty
.intro
= self
2234 self.to_s
= "{mclassdef}#{mproperty}"
2237 # Actually the name of the `mproperty`
2238 redef fun name
do return mproperty
.name
2240 # The full-name of mpropdefs combine the information about the `classdef` and the `mproperty`.
2242 # Therefore the combination of identifiers is awful,
2243 # the worst case being
2245 # * a property "p::m::A::x"
2246 # * redefined in a refinement of a class "q::n::B"
2247 # * in a module "r::o"
2248 # * so "r::o#q::n::B#p::m::A::x"
2250 # Fortunately, the full-name is simplified when entities are repeated.
2251 # For the previous case, the simplest form is "p#A#x".
2252 redef var full_name
is lazy
do
2253 var res
= new FlatBuffer
2255 # The first part is the mclassdef. Worst case is "r::o#q::n::B"
2256 res
.append mclassdef
.full_name
2260 if mclassdef
.mclass
== mproperty
.intro_mclassdef
.mclass
then
2261 # intro are unambiguous in a class
2264 # Just try to simplify each part
2265 if mclassdef
.mmodule
.mpackage
!= mproperty
.intro_mclassdef
.mmodule
.mpackage
then
2266 # precise "p::m" only if "p" != "r"
2267 res
.append mproperty
.intro_mclassdef
.mmodule
.full_name
2269 else if mproperty
.visibility
<= private_visibility
then
2270 # Same package ("p"=="q"), but private visibility,
2271 # does the module part ("::m") need to be displayed
2272 if mclassdef
.mmodule
.namespace_for
(mclassdef
.mclass
.visibility
) != mproperty
.intro_mclassdef
.mmodule
.mpackage
then
2274 res
.append mproperty
.intro_mclassdef
.mmodule
.name
2278 if mclassdef
.mclass
!= mproperty
.intro_mclassdef
.mclass
then
2279 # precise "B" only if not the same class than "A"
2280 res
.append mproperty
.intro_mclassdef
.name
2283 # Always use the property name "x"
2284 res
.append mproperty
.name
2289 redef var c_name
is lazy
do
2290 var res
= new FlatBuffer
2291 res
.append mclassdef
.c_name
2293 if mclassdef
.mclass
== mproperty
.intro_mclassdef
.mclass
then
2294 res
.append name
.to_cmangle
2296 if mclassdef
.mmodule
!= mproperty
.intro_mclassdef
.mmodule
then
2297 res
.append mproperty
.intro_mclassdef
.mmodule
.c_name
2300 if mclassdef
.mclass
!= mproperty
.intro_mclassdef
.mclass
then
2301 res
.append mproperty
.intro_mclassdef
.name
.to_cmangle
2304 res
.append mproperty
.name
.to_cmangle
2309 redef fun model
do return mclassdef
.model
2311 # Internal name combining the module, the class and the property
2312 # Example: "mymodule#MyClass#mymethod"
2313 redef var to_s
: String is noinit
2315 # Is self the definition that introduce the property?
2316 fun is_intro
: Bool do return isset mproperty
._intro
and mproperty
.intro
== self
2318 # Return the next definition in linearization of `mtype`.
2320 # This method is used to determine what method is called by a super.
2322 # REQUIRE: `not mtype.need_anchor`
2323 fun lookup_next_definition
(mmodule
: MModule, mtype
: MType): MPROPDEF
2325 assert not mtype
.need_anchor
2327 var mpropdefs
= self.mproperty
.lookup_all_definitions
(mmodule
, mtype
)
2328 var i
= mpropdefs
.iterator
2329 while i
.is_ok
and i
.item
!= self do i
.next
2330 assert has_property
: i
.is_ok
2332 assert has_next_property
: i
.is_ok
2337 # A local definition of a method
2341 redef type MPROPERTY: MMethod
2342 redef type MPROPDEF: MMethodDef
2344 # The signature attached to the property definition
2345 var msignature
: nullable MSignature = null is writable
2347 # The signature attached to the `new` call on a root-init
2348 # This is a concatenation of the signatures of the initializers
2350 # REQUIRE `mproperty.is_root_init == (new_msignature != null)`
2351 var new_msignature
: nullable MSignature = null is writable
2353 # List of initialisers to call in root-inits
2355 # They could be setters or attributes
2357 # REQUIRE `mproperty.is_root_init == (new_msignature != null)`
2358 var initializers
= new Array[MProperty]
2360 # Is the method definition abstract?
2361 var is_abstract
: Bool = false is writable
2363 # Is the method definition intern?
2364 var is_intern
= false is writable
2366 # Is the method definition extern?
2367 var is_extern
= false is writable
2369 # An optional constant value returned in functions.
2371 # Only some specific primitife value are accepted by engines.
2372 # Is used when there is no better implementation available.
2374 # Currently used only for the implementation of the `--define`
2375 # command-line option.
2376 # SEE: module `mixin`.
2377 var constant_value
: nullable Object = null is writable
2380 # A local definition of an attribute
2384 redef type MPROPERTY: MAttribute
2385 redef type MPROPDEF: MAttributeDef
2387 # The static type of the attribute
2388 var static_mtype
: nullable MType = null is writable
2391 # A local definition of a virtual type
2392 class MVirtualTypeDef
2395 redef type MPROPERTY: MVirtualTypeProp
2396 redef type MPROPDEF: MVirtualTypeDef
2398 # The bound of the virtual type
2399 var bound
: nullable MType = null is writable
2401 # Is the bound fixed?
2402 var is_fixed
= false is writable
2409 # * `interface_kind`
2413 # Note this class is basically an enum.
2414 # FIXME: use a real enum once user-defined enums are available
2416 redef var to_s
: String
2418 # Is a constructor required?
2421 # TODO: private init because enumeration.
2423 # Can a class of kind `self` specializes a class of kine `other`?
2424 fun can_specialize
(other
: MClassKind): Bool
2426 if other
== interface_kind
then return true # everybody can specialize interfaces
2427 if self == interface_kind
or self == enum_kind
then
2428 # no other case for interfaces
2430 else if self == extern_kind
then
2431 # only compatible with themselves
2432 return self == other
2433 else if other
== enum_kind
or other
== extern_kind
then
2434 # abstract_kind and concrete_kind are incompatible
2437 # remain only abstract_kind and concrete_kind
2442 # The class kind `abstract`
2443 fun abstract_kind
: MClassKind do return once
new MClassKind("abstract class", true)
2444 # The class kind `concrete`
2445 fun concrete_kind
: MClassKind do return once
new MClassKind("class", true)
2446 # The class kind `interface`
2447 fun interface_kind
: MClassKind do return once
new MClassKind("interface", false)
2448 # The class kind `enum`
2449 fun enum_kind
: MClassKind do return once
new MClassKind("enum", false)
2450 # The class kind `extern`
2451 fun extern_kind
: MClassKind do return once
new MClassKind("extern class", false)