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 for mprop
in props
do
304 assert mprop
isa MMethod
305 var intro
= mprop
.intro_mclassdef
306 for mclassdef
in recv
.mclassdefs
do
307 if not self.in_importation
.greaters
.has
(mclassdef
.mmodule
) then continue
308 if not mclassdef
.in_hierarchy
.greaters
.has
(intro
) then continue
311 else if res
!= mprop
then
312 print
("Fatal Error: ambigous property name '{name}'; conflict between {mprop.full_name} and {res.full_name}")
321 private class MClassDefSorter
323 redef type COMPARED: MClassDef
325 redef fun compare
(a
, b
)
329 if ca
!= cb
then return mmodule
.flatten_mclass_hierarchy
.compare
(ca
, cb
)
330 return mmodule
.model
.mclassdef_hierarchy
.compare
(a
, b
)
334 private class MPropDefSorter
336 redef type COMPARED: MPropDef
338 redef fun compare
(pa
, pb
)
344 if ca
!= cb
then return mmodule
.flatten_mclass_hierarchy
.compare
(ca
, cb
)
345 return mmodule
.model
.mclassdef_hierarchy
.compare
(a
, b
)
351 # `MClass` are global to the model; it means that a `MClass` is not bound to a
352 # specific `MModule`.
354 # This characteristic helps the reasoning about classes in a program since a
355 # single `MClass` object always denote the same class.
357 # The drawback is that classes (`MClass`) contain almost nothing by themselves.
358 # These do not really have properties nor belong to a hierarchy since the property and the
359 # hierarchy of a class depends of the refinement in the modules.
361 # Most services on classes require the precision of a module, and no one can asks what are
362 # the super-classes of a class nor what are properties of a class without precising what is
363 # the module considered.
365 # For instance, during the typing of a source-file, the module considered is the module of the file.
366 # eg. the question *is the method `foo` exists in the class `Bar`?* must be reformulated into
367 # *is the method `foo` exists in the class `Bar` in the current module?*
369 # During some global analysis, the module considered may be the main module of the program.
373 # The module that introduce the class
374 # While classes are not bound to a specific module,
375 # the introducing module is used for naming an visibility
376 var intro_mmodule
: MModule
378 # The short name of the class
379 # In Nit, the name of a class cannot evolve in refinements
380 redef var name
: String
382 # The canonical name of the class
384 # It is the name of the class prefixed by the full_name of the `intro_mmodule`
385 # Example: `"owner::module::MyClass"`
386 redef var full_name
is lazy
do
387 return "{self.intro_mmodule.namespace_for(visibility)}::{name}"
390 redef var c_name
is lazy
do
391 return "{intro_mmodule.c_namespace_for(visibility)}__{name.to_cmangle}"
394 # The number of generic formal parameters
395 # 0 if the class is not generic
396 var arity
: Int is noinit
398 # Each generic formal parameters in order.
399 # is empty if the class is not generic
400 var mparameters
= new Array[MParameterType]
402 # A string version of the signature a generic class.
404 # eg. `Map[K: nullable Object, V: nullable Object]`
406 # If the class in non generic the name is just given.
409 fun signature_to_s
: String
411 if arity
== 0 then return name
412 var res
= new FlatBuffer
415 for i
in [0..arity
[ do
416 if i
> 0 then res
.append
", "
417 res
.append mparameters
[i
].name
419 res
.append intro
.bound_mtype
.arguments
[i
].to_s
425 # Initialize `mparameters` from their names.
426 protected fun setup_parameter_names
(parameter_names
: nullable Array[String]) is
429 if parameter_names
== null then
432 self.arity
= parameter_names
.length
435 # Create the formal parameter types
437 assert parameter_names
!= null
438 var mparametertypes
= new Array[MParameterType]
439 for i
in [0..arity
[ do
440 var mparametertype
= new MParameterType(self, i
, parameter_names
[i
])
441 mparametertypes
.add
(mparametertype
)
443 self.mparameters
= mparametertypes
444 var mclass_type
= new MGenericType(self, mparametertypes
)
445 self.mclass_type
= mclass_type
446 self.get_mtype_cache
[mparametertypes
] = mclass_type
448 self.mclass_type
= new MClassType(self)
452 # The kind of the class (interface, abstract class, etc.)
453 # In Nit, the kind of a class cannot evolve in refinements
456 # The visibility of the class
457 # In Nit, the visibility of a class cannot evolve in refinements
458 var visibility
: MVisibility
462 intro_mmodule
.intro_mclasses
.add
(self)
463 var model
= intro_mmodule
.model
464 model
.mclasses_by_name
.add_one
(name
, self)
465 model
.mclasses
.add
(self)
468 redef fun model
do return intro_mmodule
.model
470 # All class definitions (introduction and refinements)
471 var mclassdefs
= new Array[MClassDef]
474 redef fun to_s
do return self.name
476 # The definition that introduces the class.
478 # Warning: such a definition may not exist in the early life of the object.
479 # In this case, the method will abort.
481 # Use `try_intro` instead
482 var intro
: MClassDef is noinit
484 # The definition that introduces the class or null if not yet known.
487 fun try_intro
: nullable MClassDef do
488 if isset _intro
then return _intro
else return null
491 # Return the class `self` in the class hierarchy of the module `mmodule`.
493 # SEE: `MModule::flatten_mclass_hierarchy`
494 # REQUIRE: `mmodule.has_mclass(self)`
495 fun in_hierarchy
(mmodule
: MModule): POSetElement[MClass]
497 return mmodule
.flatten_mclass_hierarchy
[self]
500 # The principal static type of the class.
502 # For non-generic class, mclass_type is the only `MClassType` based
505 # For a generic class, the arguments are the formal parameters.
506 # i.e.: for the class Array[E:Object], the `mclass_type` is Array[E].
507 # If you want Array[Object] the see `MClassDef::bound_mtype`
509 # For generic classes, the mclass_type is also the way to get a formal
510 # generic parameter type.
512 # To get other types based on a generic class, see `get_mtype`.
514 # ENSURE: `mclass_type.mclass == self`
515 var mclass_type
: MClassType is noinit
517 # Return a generic type based on the class
518 # Is the class is not generic, then the result is `mclass_type`
520 # REQUIRE: `mtype_arguments.length == self.arity`
521 fun get_mtype
(mtype_arguments
: Array[MType]): MClassType
523 assert mtype_arguments
.length
== self.arity
524 if self.arity
== 0 then return self.mclass_type
525 var res
= get_mtype_cache
.get_or_null
(mtype_arguments
)
526 if res
!= null then return res
527 res
= new MGenericType(self, mtype_arguments
)
528 self.get_mtype_cache
[mtype_arguments
.to_a
] = res
532 private var get_mtype_cache
= new HashMap[Array[MType], MGenericType]
534 # Is there a `new` factory to allow the pseudo instantiation?
535 var has_new_factory
= false is writable
537 # Is `self` a standard or abstract class kind?
538 var is_class
: Bool is lazy
do return kind
== concrete_kind
or kind
== abstract_kind
540 # Is `self` an interface kind?
541 var is_interface
: Bool is lazy
do return kind
== interface_kind
543 # Is `self` an enum kind?
544 var is_enum
: Bool is lazy
do return kind
== enum_kind
546 # Is `self` and abstract class?
547 var is_abstract
: Bool is lazy
do return kind
== abstract_kind
551 # A definition (an introduction or a refinement) of a class in a module
553 # A `MClassDef` is associated with an explicit (or almost) definition of a
554 # class. Unlike `MClass`, a `MClassDef` is a local definition that belong to
555 # a specific class and a specific module, and contains declarations like super-classes
558 # It is the class definitions that are the backbone of most things in the model:
559 # ClassDefs are defined with regard with other classdefs.
560 # Refinement and specialization are combined to produce a big poset called the `Model::mclassdef_hierarchy`.
562 # Moreover, the extension and the intention of types is defined by looking at the MClassDefs.
566 # The module where the definition is
569 # The associated `MClass`
570 var mclass
: MClass is noinit
572 # The bounded type associated to the mclassdef
574 # For a non-generic class, `bound_mtype` and `mclass.mclass_type`
578 # For the classdef Array[E: Object], the bound_mtype is Array[Object].
579 # If you want Array[E], then see `mclass.mclass_type`
581 # ENSURE: `bound_mtype.mclass == self.mclass`
582 var bound_mtype
: MClassType
584 # The origin of the definition
585 var location
: Location
587 # Internal name combining the module and the class
588 # Example: "mymodule#MyClass"
589 redef var to_s
: String is noinit
593 self.mclass
= bound_mtype
.mclass
594 mmodule
.mclassdefs
.add
(self)
595 mclass
.mclassdefs
.add
(self)
596 if mclass
.intro_mmodule
== mmodule
then
597 assert not isset mclass
._intro
600 self.to_s
= "{mmodule}#{mclass}"
603 # Actually the name of the `mclass`
604 redef fun name
do return mclass
.name
606 # The module and class name separated by a '#'.
608 # The short-name of the class is used for introduction.
609 # Example: "my_module#MyClass"
611 # The full-name of the class is used for refinement.
612 # Example: "my_module#intro_module::MyClass"
613 redef var full_name
is lazy
do
616 # private gives 'p::m#A'
617 return "{mmodule.namespace_for(mclass.visibility)}#{mclass.name}"
618 else if mclass
.intro_mmodule
.mpackage
!= mmodule
.mpackage
then
619 # public gives 'q::n#p::A'
620 # private gives 'q::n#p::m::A'
621 return "{mmodule.full_name}#{mclass.full_name}"
622 else if mclass
.visibility
> private_visibility
then
623 # public gives 'p::n#A'
624 return "{mmodule.full_name}#{mclass.name}"
626 # private gives 'p::n#::m::A' (redundant p is omitted)
627 return "{mmodule.full_name}#::{mclass.intro_mmodule.name}::{mclass.name}"
631 redef var c_name
is lazy
do
633 return "{mmodule.c_namespace_for(mclass.visibility)}___{mclass.c_name}"
634 else if mclass
.intro_mmodule
.mpackage
== mmodule
.mpackage
and mclass
.visibility
> private_visibility
then
635 return "{mmodule.c_name}___{mclass.name.to_cmangle}"
637 return "{mmodule.c_name}___{mclass.c_name}"
641 redef fun model
do return mmodule
.model
643 # All declared super-types
644 # FIXME: quite ugly but not better idea yet
645 var supertypes
= new Array[MClassType]
647 # Register some super-types for the class (ie "super SomeType")
649 # The hierarchy must not already be set
650 # REQUIRE: `self.in_hierarchy == null`
651 fun set_supertypes
(supertypes
: Array[MClassType])
653 assert unique_invocation
: self.in_hierarchy
== null
654 var mmodule
= self.mmodule
655 var model
= mmodule
.model
656 var mtype
= self.bound_mtype
658 for supertype
in supertypes
do
659 self.supertypes
.add
(supertype
)
661 # Register in full_type_specialization_hierarchy
662 model
.full_mtype_specialization_hierarchy
.add_edge
(mtype
, supertype
)
663 # Register in intro_type_specialization_hierarchy
664 if mclass
.intro_mmodule
== mmodule
and supertype
.mclass
.intro_mmodule
== mmodule
then
665 model
.intro_mtype_specialization_hierarchy
.add_edge
(mtype
, supertype
)
671 # Collect the super-types (set by set_supertypes) to build the hierarchy
673 # This function can only invoked once by class
674 # REQUIRE: `self.in_hierarchy == null`
675 # ENSURE: `self.in_hierarchy != null`
678 assert unique_invocation
: self.in_hierarchy
== null
679 var model
= mmodule
.model
680 var res
= model
.mclassdef_hierarchy
.add_node
(self)
681 self.in_hierarchy
= res
682 var mtype
= self.bound_mtype
684 # Here we need to connect the mclassdef to its pairs in the mclassdef_hierarchy
685 # The simpliest way is to attach it to collect_mclassdefs
686 for mclassdef
in mtype
.collect_mclassdefs
(mmodule
) do
687 res
.poset
.add_edge
(self, mclassdef
)
691 # The view of the class definition in `mclassdef_hierarchy`
692 var in_hierarchy
: nullable POSetElement[MClassDef] = null
694 # Is the definition the one that introduced `mclass`?
695 fun is_intro
: Bool do return isset mclass
._intro
and mclass
.intro
== self
697 # All properties introduced by the classdef
698 var intro_mproperties
= new Array[MProperty]
700 # All property definitions in the class (introductions and redefinitions)
701 var mpropdefs
= new Array[MPropDef]
704 # A global static type
706 # MType are global to the model; it means that a `MType` is not bound to a
707 # specific `MModule`.
708 # This characteristic helps the reasoning about static types in a program
709 # since a single `MType` object always denote the same type.
711 # However, because a `MType` is global, it does not really have properties
712 # nor have subtypes to a hierarchy since the property and the class hierarchy
713 # depends of a module.
714 # Moreover, virtual types an formal generic parameter types also depends on
715 # a receiver to have sense.
717 # Therefore, most method of the types require a module and an anchor.
718 # The module is used to know what are the classes and the specialization
720 # The anchor is used to know what is the bound of the virtual types and formal
721 # generic parameter types.
723 # MType are not directly usable to get properties. See the `anchor_to` method
724 # and the `MClassType` class.
726 # FIXME: the order of the parameters is not the best. We mus pick on from:
727 # * foo(mmodule, anchor, othertype)
728 # * foo(othertype, anchor, mmodule)
729 # * foo(anchor, mmodule, othertype)
730 # * foo(othertype, mmodule, anchor)
734 redef fun name
do return to_s
736 # Return true if `self` is an subtype of `sup`.
737 # The typing is done using the standard typing policy of Nit.
739 # REQUIRE: `anchor == null implies not self.need_anchor and not sup.need_anchor`
740 # REQUIRE: `anchor != null implies self.can_resolve_for(anchor, null, mmodule) and sup.can_resolve_for(anchor, null, mmodule)`
741 fun is_subtype
(mmodule
: MModule, anchor
: nullable MClassType, sup
: MType): Bool
744 if sub
== sup
then return true
746 #print "1.is {sub} a {sup}? ===="
748 if anchor
== null then
749 assert not sub
.need_anchor
750 assert not sup
.need_anchor
752 # First, resolve the formal types to the simplest equivalent forms in the receiver
753 assert sub
.can_resolve_for
(anchor
, null, mmodule
)
754 sub
= sub
.lookup_fixed
(mmodule
, anchor
)
755 assert sup
.can_resolve_for
(anchor
, null, mmodule
)
756 sup
= sup
.lookup_fixed
(mmodule
, anchor
)
759 # Does `sup` accept null or not?
760 # Discard the nullable marker if it exists
761 var sup_accept_null
= false
762 if sup
isa MNullableType then
763 sup_accept_null
= true
765 else if sup
isa MNotNullType then
767 else if sup
isa MNullType then
768 sup_accept_null
= true
771 # Can `sub` provide null or not?
772 # Thus we can match with `sup_accept_null`
773 # Also discard the nullable marker if it exists
774 var sub_reject_null
= false
775 if sub
isa MNullableType then
776 if not sup_accept_null
then return false
778 else if sub
isa MNotNullType then
779 sub_reject_null
= true
781 else if sub
isa MNullType then
782 return sup_accept_null
784 # Now the case of direct null and nullable is over.
786 # If `sub` is a formal type, then it is accepted if its bound is accepted
787 while sub
isa MFormalType do
788 #print "3.is {sub} a {sup}?"
790 # A unfixed formal type can only accept itself
791 if sub
== sup
then return true
793 assert anchor
!= null
794 sub
= sub
.lookup_bound
(mmodule
, anchor
)
795 if sub_reject_null
then sub
= sub
.as_notnull
797 #print "3.is {sub} a {sup}?"
799 # Manage the second layer of null/nullable
800 if sub
isa MNullableType then
801 if not sup_accept_null
and not sub_reject_null
then return false
803 else if sub
isa MNotNullType then
804 sub_reject_null
= true
806 else if sub
isa MNullType then
807 return sup_accept_null
810 #print "4.is {sub} a {sup}? <- no more resolution"
812 if sub
isa MBottomType then
816 assert sub
isa MClassType else print
"{sub} <? {sub}" # It is the only remaining type
818 # Handle sup-type when the sub-type is class-based (other cases must have be identified before).
819 if sup
isa MFormalType or sup
isa MNullType or sup
isa MBottomType then
820 # These types are not super-types of Class-based types.
824 assert sup
isa MClassType else print
"got {sup} {sub.inspect}" # It is the only remaining type
826 # Now both are MClassType, we need to dig
828 if sub
== sup
then return true
830 if anchor
== null then anchor
= sub
# UGLY: any anchor will work
831 var resolved_sub
= sub
.anchor_to
(mmodule
, anchor
)
832 var res
= resolved_sub
.collect_mclasses
(mmodule
).has
(sup
.mclass
)
833 if res
== false then return false
834 if not sup
isa MGenericType then return true
835 var sub2
= sub
.supertype_to
(mmodule
, anchor
, sup
.mclass
)
836 assert sub2
.mclass
== sup
.mclass
837 for i
in [0..sup
.mclass
.arity
[ do
838 var sub_arg
= sub2
.arguments
[i
]
839 var sup_arg
= sup
.arguments
[i
]
840 res
= sub_arg
.is_subtype
(mmodule
, anchor
, sup_arg
)
841 if res
== false then return false
846 # The base class type on which self is based
848 # This base type is used to get property (an internally to perform
849 # unsafe type comparison).
851 # Beware: some types (like null) are not based on a class thus this
854 # Basically, this function transform the virtual types and parameter
855 # types to their bounds.
860 # class B super A end
862 # class Y super X end
871 # Map[T,U] anchor_to H #-> Map[B,Y]
873 # Explanation of the example:
874 # In H, T is set to B, because "H super G[B]", and U is bound to Y,
875 # because "redef type U: Y". Therefore, Map[T, U] is bound to
878 # ENSURE: `not self.need_anchor implies result == self`
879 # ENSURE: `not result.need_anchor`
880 fun anchor_to
(mmodule
: MModule, anchor
: MClassType): MType
882 if not need_anchor
then return self
883 assert not anchor
.need_anchor
884 # Just resolve to the anchor and clear all the virtual types
885 var res
= self.resolve_for
(anchor
, null, mmodule
, true)
886 assert not res
.need_anchor
890 # Does `self` contain a virtual type or a formal generic parameter type?
891 # In order to remove those types, you usually want to use `anchor_to`.
892 fun need_anchor
: Bool do return true
894 # Return the supertype when adapted to a class.
896 # In Nit, for each super-class of a type, there is a equivalent super-type.
902 # class H[V] super G[V, Bool] end
904 # H[Int] supertype_to G #-> G[Int, Bool]
907 # REQUIRE: `super_mclass` is a super-class of `self`
908 # REQUIRE: `self.need_anchor implies anchor != null and self.can_resolve_for(anchor, null, mmodule)`
909 # ENSURE: `result.mclass = super_mclass`
910 fun supertype_to
(mmodule
: MModule, anchor
: nullable MClassType, super_mclass
: MClass): MClassType
912 if super_mclass
.arity
== 0 then return super_mclass
.mclass_type
913 if self isa MClassType and self.mclass
== super_mclass
then return self
915 if self.need_anchor
then
916 assert anchor
!= null
917 resolved_self
= self.anchor_to
(mmodule
, anchor
)
921 var supertypes
= resolved_self
.collect_mtypes
(mmodule
)
922 for supertype
in supertypes
do
923 if supertype
.mclass
== super_mclass
then
924 # FIXME: Here, we stop on the first goal. Should we check others and detect inconsistencies?
925 return supertype
.resolve_for
(self, anchor
, mmodule
, false)
931 # Replace formals generic types in self with resolved values in `mtype`
932 # If `cleanup_virtual` is true, then virtual types are also replaced
935 # This function returns self if `need_anchor` is false.
941 # class H[F] super G[F] end
945 # * Array[E].resolve_for(H[Int]) #-> Array[Int]
946 # * Array[E].resolve_for(G[Z], X[Int]) #-> Array[Z]
948 # Explanation of the example:
949 # * Array[E].need_anchor is true because there is a formal generic parameter type E
950 # * E makes sense for H[Int] because E is a formal parameter of G and H specialize G
951 # * Since "H[F] super G[F]", E is in fact F for H
952 # * More specifically, in H[Int], E is Int
953 # * So, in H[Int], Array[E] is Array[Int]
955 # This function is mainly used to inherit a signature.
956 # Because, unlike `anchor_to`, we do not want a full resolution of
957 # a type but only an adapted version of it.
963 # fun foo(e:E):E is abstract
965 # class B super A[Int] end
968 # The signature on foo is (e: E): E
969 # If we resolve the signature for B, we get (e:Int):Int
975 # fun foo(e:E):E is abstract
979 # fun bar do a.foo(x) # <- x is here
983 # The first question is: is foo available on `a`?
985 # The static type of a is `A[Array[F]]`, that is an open type.
986 # in order to find a method `foo`, whe must look at a resolved type.
988 # A[Array[F]].anchor_to(C[nullable Object]) #-> A[Array[nullable Object]]
990 # the method `foo` exists in `A[Array[nullable Object]]`, therefore `foo` exists for `a`.
992 # The next question is: what is the accepted types for `x`?
994 # the signature of `foo` is `foo(e:E)`, thus we must resolve the type E
996 # E.resolve_for(A[Array[F]],C[nullable Object]) #-> Array[F]
998 # The resolution can be done because `E` make sense for the class A (see `can_resolve_for`)
1000 # FIXME: the parameter `cleanup_virtual` is just a bad idea, but having
1001 # two function instead of one seems also to be a bad idea.
1003 # REQUIRE: `can_resolve_for(mtype, anchor, mmodule)`
1004 # ENSURE: `not self.need_anchor implies result == self`
1005 fun resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule, cleanup_virtual
: Bool): MType is abstract
1007 # Resolve formal type to its verbatim bound.
1008 # If the type is not formal, just return self
1010 # The result is returned exactly as declared in the "type" property (verbatim).
1011 # So it could be another formal type.
1013 # In case of conflicts or inconsistencies in the model, the method returns a `MBottomType`.
1014 fun lookup_bound
(mmodule
: MModule, resolved_receiver
: MType): MType do return self
1016 # Resolve the formal type to its simplest equivalent form.
1018 # Formal types are either free or fixed.
1019 # When it is fixed, it means that it is equivalent with a simpler type.
1020 # When a formal type is free, it means that it is only equivalent with itself.
1021 # This method return the most simple equivalent type of `self`.
1023 # This method is mainly used for subtype test in order to sanely compare fixed.
1025 # By default, return self.
1026 # See the redefinitions for specific behavior in each kind of type.
1028 # In case of conflicts or inconsistencies in the model, the method returns a `MBottomType`.
1029 fun lookup_fixed
(mmodule
: MModule, resolved_receiver
: MType): MType do return self
1031 # Can the type be resolved?
1033 # In order to resolve open types, the formal types must make sence.
1043 # E.can_resolve_for(A[Int]) #-> true, E make sense in A
1045 # E.can_resolve_for(B[Int]) #-> false, E does not make sense in B
1047 # B[E].can_resolve_for(A[F], B[Object]) #-> true,
1048 # # B[E] is a red hearing only the E is important,
1049 # # E make sense in A
1052 # REQUIRE: `anchor != null implies not anchor.need_anchor`
1053 # REQUIRE: `mtype.need_anchor implies anchor != null and mtype.can_resolve_for(anchor, null, mmodule)`
1054 # ENSURE: `not self.need_anchor implies result == true`
1055 fun can_resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule): Bool is abstract
1057 # Return the nullable version of the type
1058 # If the type is already nullable then self is returned
1059 fun as_nullable
: MType
1061 var res
= self.as_nullable_cache
1062 if res
!= null then return res
1063 res
= new MNullableType(self)
1064 self.as_nullable_cache
= res
1068 # Remove the base type of a decorated (proxy) type.
1069 # Is the type is not decorated, then self is returned.
1071 # Most of the time it is used to return the not nullable version of a nullable type.
1072 # In this case, this just remove the `nullable` notation, but the result can still contains null.
1073 # For instance if `self isa MNullType` or self is a formal type bounded by a nullable type.
1074 # If you really want to exclude the `null` value, then use `as_notnull`
1075 fun undecorate
: MType
1080 # Returns the not null version of the type.
1081 # That is `self` minus the `null` value.
1083 # For most types, this return `self`.
1084 # For formal types, this returns a special `MNotNullType`
1085 fun as_notnull
: MType do return self
1087 private var as_nullable_cache
: nullable MType = null
1090 # The depth of the type seen as a tree.
1097 # Formal types have a depth of 1.
1103 # The length of the type seen as a tree.
1110 # Formal types have a length of 1.
1116 # Compute all the classdefs inherited/imported.
1117 # The returned set contains:
1118 # * the class definitions from `mmodule` and its imported modules
1119 # * the class definitions of this type and its super-types
1121 # This function is used mainly internally.
1123 # REQUIRE: `not self.need_anchor`
1124 fun collect_mclassdefs
(mmodule
: MModule): Set[MClassDef] is abstract
1126 # Compute all the super-classes.
1127 # This function is used mainly internally.
1129 # REQUIRE: `not self.need_anchor`
1130 fun collect_mclasses
(mmodule
: MModule): Set[MClass] is abstract
1132 # Compute all the declared super-types.
1133 # Super-types are returned as declared in the classdefs (verbatim).
1134 # This function is used mainly internally.
1136 # REQUIRE: `not self.need_anchor`
1137 fun collect_mtypes
(mmodule
: MModule): Set[MClassType] is abstract
1139 # Is the property in self for a given module
1140 # This method does not filter visibility or whatever
1142 # REQUIRE: `not self.need_anchor`
1143 fun has_mproperty
(mmodule
: MModule, mproperty
: MProperty): Bool
1145 assert not self.need_anchor
1146 return self.collect_mclassdefs
(mmodule
).has
(mproperty
.intro_mclassdef
)
1150 # A type based on a class.
1152 # `MClassType` have properties (see `has_mproperty`).
1156 # The associated class
1159 redef fun model
do return self.mclass
.intro_mmodule
.model
1161 # TODO: private init because strongly bounded to its mclass. see `mclass.mclass_type`
1163 # The formal arguments of the type
1164 # ENSURE: `result.length == self.mclass.arity`
1165 var arguments
= new Array[MType]
1167 redef fun to_s
do return mclass
.to_s
1169 redef fun full_name
do return mclass
.full_name
1171 redef fun c_name
do return mclass
.c_name
1173 redef fun need_anchor
do return false
1175 redef fun anchor_to
(mmodule
: MModule, anchor
: MClassType): MClassType
1177 return super.as(MClassType)
1180 redef fun resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule, cleanup_virtual
: Bool): MClassType do return self
1182 redef fun can_resolve_for
(mtype
, anchor
, mmodule
) do return true
1184 redef fun collect_mclassdefs
(mmodule
)
1186 assert not self.need_anchor
1187 var cache
= self.collect_mclassdefs_cache
1188 if not cache
.has_key
(mmodule
) then
1189 self.collect_things
(mmodule
)
1191 return cache
[mmodule
]
1194 redef fun collect_mclasses
(mmodule
)
1196 if collect_mclasses_last_module
== mmodule
then return collect_mclasses_last_module_cache
1197 assert not self.need_anchor
1198 var cache
= self.collect_mclasses_cache
1199 if not cache
.has_key
(mmodule
) then
1200 self.collect_things
(mmodule
)
1202 var res
= cache
[mmodule
]
1203 collect_mclasses_last_module
= mmodule
1204 collect_mclasses_last_module_cache
= res
1208 private var collect_mclasses_last_module
: nullable MModule = null
1209 private var collect_mclasses_last_module_cache
: Set[MClass] is noinit
1211 redef fun collect_mtypes
(mmodule
)
1213 assert not self.need_anchor
1214 var cache
= self.collect_mtypes_cache
1215 if not cache
.has_key
(mmodule
) then
1216 self.collect_things
(mmodule
)
1218 return cache
[mmodule
]
1221 # common implementation for `collect_mclassdefs`, `collect_mclasses`, and `collect_mtypes`.
1222 private fun collect_things
(mmodule
: MModule)
1224 var res
= new HashSet[MClassDef]
1225 var seen
= new HashSet[MClass]
1226 var types
= new HashSet[MClassType]
1227 seen
.add
(self.mclass
)
1228 var todo
= [self.mclass
]
1229 while not todo
.is_empty
do
1230 var mclass
= todo
.pop
1231 #print "process {mclass}"
1232 for mclassdef
in mclass
.mclassdefs
do
1233 if not mmodule
.in_importation
<= mclassdef
.mmodule
then continue
1234 #print " process {mclassdef}"
1236 for supertype
in mclassdef
.supertypes
do
1237 types
.add
(supertype
)
1238 var superclass
= supertype
.mclass
1239 if seen
.has
(superclass
) then continue
1240 #print " add {superclass}"
1241 seen
.add
(superclass
)
1242 todo
.add
(superclass
)
1246 collect_mclassdefs_cache
[mmodule
] = res
1247 collect_mclasses_cache
[mmodule
] = seen
1248 collect_mtypes_cache
[mmodule
] = types
1251 private var collect_mclassdefs_cache
= new HashMap[MModule, Set[MClassDef]]
1252 private var collect_mclasses_cache
= new HashMap[MModule, Set[MClass]]
1253 private var collect_mtypes_cache
= new HashMap[MModule, Set[MClassType]]
1257 # A type based on a generic class.
1258 # A generic type a just a class with additional formal generic arguments.
1264 # TODO: private init because strongly bounded to its mclass. see `mclass.get_mtype`
1268 assert self.mclass
.arity
== arguments
.length
1270 self.need_anchor
= false
1271 for t
in arguments
do
1272 if t
.need_anchor
then
1273 self.need_anchor
= true
1278 self.to_s
= "{mclass}[{arguments.join(", ")}]"
1281 # The short-name of the class, then the full-name of each type arguments within brackets.
1282 # Example: `"Map[String, List[Int]]"`
1283 redef var to_s
: String is noinit
1285 # The full-name of the class, then the full-name of each type arguments within brackets.
1286 # Example: `"core::Map[core::String, core::List[core::Int]]"`
1287 redef var full_name
is lazy
do
1288 var args
= new Array[String]
1289 for t
in arguments
do
1290 args
.add t
.full_name
1292 return "{mclass.full_name}[{args.join(", ")}]"
1295 redef var c_name
is lazy
do
1296 var res
= mclass
.c_name
1297 # Note: because the arity is known, a prefix notation is enough
1298 for t
in arguments
do
1305 redef var need_anchor
: Bool is noinit
1307 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1309 if not need_anchor
then return self
1310 assert can_resolve_for
(mtype
, anchor
, mmodule
)
1311 var types
= new Array[MType]
1312 for t
in arguments
do
1313 types
.add
(t
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
))
1315 return mclass
.get_mtype
(types
)
1318 redef fun can_resolve_for
(mtype
, anchor
, mmodule
)
1320 if not need_anchor
then return true
1321 for t
in arguments
do
1322 if not t
.can_resolve_for
(mtype
, anchor
, mmodule
) then return false
1331 for a
in self.arguments
do
1333 if d
> dmax
then dmax
= d
1341 for a
in self.arguments
do
1348 # A formal type (either virtual of parametric).
1350 # The main issue with formal types is that they offer very little information on their own
1351 # and need a context (anchor and mmodule) to be useful.
1352 abstract class MFormalType
1355 redef var as_notnull
= new MNotNullType(self) is lazy
1358 # A virtual formal type.
1362 # The property associated with the type.
1363 # Its the definitions of this property that determine the bound or the virtual type.
1364 var mproperty
: MVirtualTypeProp
1366 redef fun model
do return self.mproperty
.intro_mclassdef
.mmodule
.model
1368 redef fun lookup_bound
(mmodule
: MModule, resolved_receiver
: MType): MType
1370 return lookup_single_definition
(mmodule
, resolved_receiver
).bound
or else new MBottomType(model
)
1373 private fun lookup_single_definition
(mmodule
: MModule, resolved_receiver
: MType): MVirtualTypeDef
1375 assert not resolved_receiver
.need_anchor
1376 var props
= self.mproperty
.lookup_definitions
(mmodule
, resolved_receiver
)
1377 if props
.is_empty
then
1379 else if props
.length
== 1 then
1382 var types
= new ArraySet[MType]
1383 var res
= props
.first
1385 types
.add
(p
.bound
.as(not null))
1386 if not res
.is_fixed
then res
= p
1388 if types
.length
== 1 then
1394 # A VT is fixed when:
1395 # * the VT is (re-)defined with the annotation `is fixed`
1396 # * the VT is (indirectly) bound to an enum class (see `enum_kind`) since there is no subtype possible
1397 # * the receiver is an enum class since there is no subtype possible
1398 redef fun lookup_fixed
(mmodule
: MModule, resolved_receiver
: MType): MType
1400 assert not resolved_receiver
.need_anchor
1401 resolved_receiver
= resolved_receiver
.undecorate
1402 assert resolved_receiver
isa MClassType # It is the only remaining type
1404 var prop
= lookup_single_definition
(mmodule
, resolved_receiver
)
1405 var res
= prop
.bound
1406 if res
== null then return new MBottomType(model
)
1408 # Recursively lookup the fixed result
1409 res
= res
.lookup_fixed
(mmodule
, resolved_receiver
)
1411 # 1. For a fixed VT, return the resolved bound
1412 if prop
.is_fixed
then return res
1414 # 2. For a enum boud, return the bound
1415 if res
isa MClassType and res
.mclass
.kind
== enum_kind
then return res
1417 # 3. for a enum receiver return the bound
1418 if resolved_receiver
.mclass
.kind
== enum_kind
then return res
1423 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1425 if not cleanup_virtual
then return self
1426 assert can_resolve_for
(mtype
, anchor
, mmodule
)
1427 # self is a virtual type declared (or inherited) in mtype
1428 # The point of the function it to get the bound of the virtual type that make sense for mtype
1429 # But because mtype is maybe a virtual/formal type, we need to get a real receiver first
1430 #print "{class_name}: {self}/{mtype}/{anchor}?"
1431 var resolved_receiver
1432 if mtype
.need_anchor
then
1433 assert anchor
!= null
1434 resolved_receiver
= mtype
.resolve_for
(anchor
, null, mmodule
, true)
1436 resolved_receiver
= mtype
1438 # Now, we can get the bound
1439 var verbatim_bound
= lookup_bound
(mmodule
, resolved_receiver
)
1440 # The bound is exactly as declared in the "type" property, so we must resolve it again
1441 var res
= verbatim_bound
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1446 redef fun can_resolve_for
(mtype
, anchor
, mmodule
)
1448 if mtype
.need_anchor
then
1449 assert anchor
!= null
1450 mtype
= mtype
.anchor_to
(mmodule
, anchor
)
1452 return mtype
.has_mproperty
(mmodule
, mproperty
)
1455 redef fun to_s
do return self.mproperty
.to_s
1457 redef fun full_name
do return self.mproperty
.full_name
1459 redef fun c_name
do return self.mproperty
.c_name
1462 # The type associated to a formal parameter generic type of a class
1464 # Each parameter type is associated to a specific class.
1465 # It means that all refinements of a same class "share" the parameter type,
1466 # but that a generic subclass has its own parameter types.
1468 # However, in the sense of the meta-model, a parameter type of a class is
1469 # a valid type in a subclass. The "in the sense of the meta-model" is
1470 # important because, in the Nit language, the programmer cannot refers
1471 # directly to the parameter types of the super-classes.
1476 # fun e: E is abstract
1482 # In the class definition B[F], `F` is a valid type but `E` is not.
1483 # However, `self.e` is a valid method call, and the signature of `e` is
1486 # Note that parameter types are shared among class refinements.
1487 # Therefore parameter only have an internal name (see `to_s` for details).
1488 class MParameterType
1491 # The generic class where the parameter belong
1494 redef fun model
do return self.mclass
.intro_mmodule
.model
1496 # The position of the parameter (0 for the first parameter)
1497 # FIXME: is `position` a better name?
1502 redef fun to_s
do return name
1504 redef var full_name
is lazy
do return "{mclass.full_name}::{name}"
1506 redef var c_name
is lazy
do return mclass
.c_name
+ "__" + "#{name}".to_cmangle
1508 redef fun lookup_bound
(mmodule
: MModule, resolved_receiver
: MType): MType
1510 assert not resolved_receiver
.need_anchor
1511 resolved_receiver
= resolved_receiver
.undecorate
1512 assert resolved_receiver
isa MClassType # It is the only remaining type
1513 var goalclass
= self.mclass
1514 if resolved_receiver
.mclass
== goalclass
then
1515 return resolved_receiver
.arguments
[self.rank
]
1517 var supertypes
= resolved_receiver
.collect_mtypes
(mmodule
)
1518 for t
in supertypes
do
1519 if t
.mclass
== goalclass
then
1520 # Yeah! c specialize goalclass with a "super `t'". So the question is what is the argument of f
1521 # FIXME: Here, we stop on the first goal. Should we check others and detect inconsistencies?
1522 var res
= t
.arguments
[self.rank
]
1529 # A PT is fixed when:
1530 # * Its bound is a enum class (see `enum_kind`).
1531 # The PT is just useless, but it is still a case.
1532 # * More usually, the `resolved_receiver` is a subclass of `self.mclass`,
1533 # so it is necessarily fixed in a `super` clause, either with a normal type
1534 # or with another PT.
1535 # See `resolve_for` for examples about related issues.
1536 redef fun lookup_fixed
(mmodule
: MModule, resolved_receiver
: MType): MType
1538 assert not resolved_receiver
.need_anchor
1539 resolved_receiver
= resolved_receiver
.undecorate
1540 assert resolved_receiver
isa MClassType # It is the only remaining type
1541 var res
= self.resolve_for
(resolved_receiver
.mclass
.mclass_type
, resolved_receiver
, mmodule
, false)
1545 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1547 assert can_resolve_for
(mtype
, anchor
, mmodule
)
1548 #print "{class_name}: {self}/{mtype}/{anchor}?"
1550 if mtype
isa MGenericType and mtype
.mclass
== self.mclass
then
1551 var res
= mtype
.arguments
[self.rank
]
1552 if anchor
!= null and res
.need_anchor
then
1553 # Maybe the result can be resolved more if are bound to a final class
1554 var r2
= res
.anchor_to
(mmodule
, anchor
)
1555 if r2
isa MClassType and r2
.mclass
.kind
== enum_kind
then return r2
1560 # self is a parameter type of mtype (or of a super-class of mtype)
1561 # The point of the function it to get the bound of the virtual type that make sense for mtype
1562 # But because mtype is maybe a virtual/formal type, we need to get a real receiver first
1563 # FIXME: What happens here is far from clear. Thus this part must be validated and clarified
1564 var resolved_receiver
1565 if mtype
.need_anchor
then
1566 assert anchor
!= null
1567 resolved_receiver
= mtype
.resolve_for
(anchor
.mclass
.mclass_type
, anchor
, mmodule
, true)
1569 resolved_receiver
= mtype
1571 if resolved_receiver
isa MNullableType then resolved_receiver
= resolved_receiver
.mtype
1572 if resolved_receiver
isa MParameterType then
1573 assert anchor
!= null
1574 assert resolved_receiver
.mclass
== anchor
.mclass
1575 resolved_receiver
= anchor
.arguments
[resolved_receiver
.rank
]
1576 if resolved_receiver
isa MNullableType then resolved_receiver
= resolved_receiver
.mtype
1578 assert resolved_receiver
isa MClassType # It is the only remaining type
1580 # Eh! The parameter is in the current class.
1581 # So we return the corresponding argument, no mater what!
1582 if resolved_receiver
.mclass
== self.mclass
then
1583 var res
= resolved_receiver
.arguments
[self.rank
]
1584 #print "{class_name}: {self}/{mtype}/{anchor} -> direct {res}"
1588 if resolved_receiver
.need_anchor
then
1589 assert anchor
!= null
1590 resolved_receiver
= resolved_receiver
.resolve_for
(anchor
, null, mmodule
, false)
1592 # Now, we can get the bound
1593 var verbatim_bound
= lookup_bound
(mmodule
, resolved_receiver
)
1594 # The bound is exactly as declared in the "type" property, so we must resolve it again
1595 var res
= verbatim_bound
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1597 #print "{class_name}: {self}/{mtype}/{anchor} -> indirect {res}"
1602 redef fun can_resolve_for
(mtype
, anchor
, mmodule
)
1604 if mtype
.need_anchor
then
1605 assert anchor
!= null
1606 mtype
= mtype
.anchor_to
(mmodule
, anchor
)
1608 return mtype
.collect_mclassdefs
(mmodule
).has
(mclass
.intro
)
1612 # A type that decorates another type.
1614 # The point of this class is to provide a common implementation of sevices that just forward to the original type.
1615 # Specific decorator are expected to redefine (or to extend) the default implementation as this suit them.
1616 abstract class MProxyType
1621 redef fun model
do return self.mtype
.model
1622 redef fun need_anchor
do return mtype
.need_anchor
1623 redef fun as_nullable
do return mtype
.as_nullable
1624 redef fun as_notnull
do return mtype
.as_notnull
1625 redef fun undecorate
do return mtype
.undecorate
1626 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1628 var res
= self.mtype
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1632 redef fun can_resolve_for
(mtype
, anchor
, mmodule
)
1634 return self.mtype
.can_resolve_for
(mtype
, anchor
, mmodule
)
1637 redef fun lookup_fixed
(mmodule
, resolved_receiver
)
1639 var t
= mtype
.lookup_fixed
(mmodule
, resolved_receiver
)
1643 redef fun depth
do return self.mtype
.depth
1645 redef fun length
do return self.mtype
.length
1647 redef fun collect_mclassdefs
(mmodule
)
1649 assert not self.need_anchor
1650 return self.mtype
.collect_mclassdefs
(mmodule
)
1653 redef fun collect_mclasses
(mmodule
)
1655 assert not self.need_anchor
1656 return self.mtype
.collect_mclasses
(mmodule
)
1659 redef fun collect_mtypes
(mmodule
)
1661 assert not self.need_anchor
1662 return self.mtype
.collect_mtypes
(mmodule
)
1666 # A type prefixed with "nullable"
1672 self.to_s
= "nullable {mtype}"
1675 redef var to_s
: String is noinit
1677 redef var full_name
is lazy
do return "nullable {mtype.full_name}"
1679 redef var c_name
is lazy
do return "nullable__{mtype.c_name}"
1681 redef fun as_nullable
do return self
1682 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1685 return res
.as_nullable
1688 # Efficiently returns `mtype.lookup_fixed(mmodule, resolved_receiver).as_nullable`
1689 redef fun lookup_fixed
(mmodule
, resolved_receiver
)
1692 if t
== mtype
then return self
1693 return t
.as_nullable
1697 # A non-null version of a formal type.
1699 # When a formal type in bounded to a nullable type, this is the type of the not null version of it.
1703 redef fun to_s
do return "not null {mtype}"
1704 redef var full_name
is lazy
do return "not null {mtype.full_name}"
1705 redef var c_name
is lazy
do return "notnull__{mtype.c_name}"
1707 redef fun as_notnull
do return self
1709 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1712 return res
.as_notnull
1715 # Efficiently returns `mtype.lookup_fixed(mmodule, resolved_receiver).as_notnull`
1716 redef fun lookup_fixed
(mmodule
, resolved_receiver
)
1719 if t
== mtype
then return self
1724 # The type of the only value null
1726 # The is only one null type per model, see `MModel::null_type`.
1729 redef var model
: Model
1730 redef fun to_s
do return "null"
1731 redef fun full_name
do return "null"
1732 redef fun c_name
do return "null"
1733 redef fun as_nullable
do return self
1735 redef var as_notnull
= new MBottomType(model
) is lazy
1736 redef fun need_anchor
do return false
1737 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
) do return self
1738 redef fun can_resolve_for
(mtype
, anchor
, mmodule
) do return true
1740 redef fun collect_mclassdefs
(mmodule
) do return new HashSet[MClassDef]
1742 redef fun collect_mclasses
(mmodule
) do return new HashSet[MClass]
1744 redef fun collect_mtypes
(mmodule
) do return new HashSet[MClassType]
1747 # The special universal most specific type.
1749 # This type is intended to be only used internally for type computation or analysis and should not be exposed to the user.
1750 # The bottom type can de used to denote things that are absurd, dead, or the absence of knowledge.
1752 # Semantically it is the singleton `null.as_notnull`.
1755 redef var model
: Model
1756 redef fun to_s
do return "bottom"
1757 redef fun full_name
do return "bottom"
1758 redef fun c_name
do return "bottom"
1759 redef fun as_nullable
do return model
.null_type
1760 redef fun as_notnull
do return self
1761 redef fun need_anchor
do return false
1762 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
) do return self
1763 redef fun can_resolve_for
(mtype
, anchor
, mmodule
) do return true
1765 redef fun collect_mclassdefs
(mmodule
) do return new HashSet[MClassDef]
1767 redef fun collect_mclasses
(mmodule
) do return new HashSet[MClass]
1769 redef fun collect_mtypes
(mmodule
) do return new HashSet[MClassType]
1772 # A signature of a method
1776 # The each parameter (in order)
1777 var mparameters
: Array[MParameter]
1779 # Returns a parameter named `name`, if any.
1780 fun mparameter_by_name
(name
: String): nullable MParameter
1782 for p
in mparameters
do
1783 if p
.name
== name
then return p
1788 # The return type (null for a procedure)
1789 var return_mtype
: nullable MType
1794 var t
= self.return_mtype
1795 if t
!= null then dmax
= t
.depth
1796 for p
in mparameters
do
1797 var d
= p
.mtype
.depth
1798 if d
> dmax
then dmax
= d
1806 var t
= self.return_mtype
1807 if t
!= null then res
+= t
.length
1808 for p
in mparameters
do
1809 res
+= p
.mtype
.length
1814 # REQUIRE: 1 <= mparameters.count p -> p.is_vararg
1817 var vararg_rank
= -1
1818 for i
in [0..mparameters
.length
[ do
1819 var parameter
= mparameters
[i
]
1820 if parameter
.is_vararg
then
1821 assert vararg_rank
== -1
1825 self.vararg_rank
= vararg_rank
1828 # The rank of the ellipsis (`...`) for vararg (starting from 0).
1829 # value is -1 if there is no vararg.
1830 # Example: for "(a: Int, b: Bool..., c: Char)" #-> vararg_rank=1
1831 var vararg_rank
: Int is noinit
1833 # The number of parameters
1834 fun arity
: Int do return mparameters
.length
1838 var b
= new FlatBuffer
1839 if not mparameters
.is_empty
then
1841 for i
in [0..mparameters
.length
[ do
1842 var mparameter
= mparameters
[i
]
1843 if i
> 0 then b
.append
(", ")
1844 b
.append
(mparameter
.name
)
1846 b
.append
(mparameter
.mtype
.to_s
)
1847 if mparameter
.is_vararg
then
1853 var ret
= self.return_mtype
1861 redef fun resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule, cleanup_virtual
: Bool): MSignature
1863 var params
= new Array[MParameter]
1864 for p
in self.mparameters
do
1865 params
.add
(p
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
))
1867 var ret
= self.return_mtype
1869 ret
= ret
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1871 var res
= new MSignature(params
, ret
)
1876 # A parameter in a signature
1880 # The name of the parameter
1881 redef var name
: String
1883 # The static type of the parameter
1886 # Is the parameter a vararg?
1892 return "{name}: {mtype}..."
1894 return "{name}: {mtype}"
1898 # Returns a new parameter with the `mtype` resolved.
1899 # See `MType::resolve_for` for details.
1900 fun resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule, cleanup_virtual
: Bool): MParameter
1902 if not self.mtype
.need_anchor
then return self
1903 var newtype
= self.mtype
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1904 var res
= new MParameter(self.name
, newtype
, self.is_vararg
)
1908 redef fun model
do return mtype
.model
1911 # A service (global property) that generalize method, attribute, etc.
1913 # `MProperty` are global to the model; it means that a `MProperty` is not bound
1914 # to a specific `MModule` nor a specific `MClass`.
1916 # A MProperty gather definitions (see `mpropdefs`) ; one for the introduction
1917 # and the other in subclasses and in refinements.
1919 # A `MProperty` is used to denotes services in polymorphic way (ie. independent
1920 # of any dynamic type).
1921 # For instance, a call site "x.foo" is associated to a `MProperty`.
1922 abstract class MProperty
1925 # The associated MPropDef subclass.
1926 # The two specialization hierarchy are symmetric.
1927 type MPROPDEF: MPropDef
1929 # The classdef that introduce the property
1930 # While a property is not bound to a specific module, or class,
1931 # the introducing mclassdef is used for naming and visibility
1932 var intro_mclassdef
: MClassDef
1934 # The (short) name of the property
1935 redef var name
: String
1937 # The canonical name of the property.
1939 # It is the short-`name` prefixed by the short-name of the class and the full-name of the module.
1940 # Example: "my_package::my_module::MyClass::my_method"
1941 redef var full_name
is lazy
do
1942 return "{intro_mclassdef.mmodule.namespace_for(visibility)}::{intro_mclassdef.mclass.name}::{name}"
1945 redef var c_name
is lazy
do
1946 # FIXME use `namespace_for`
1947 return "{intro_mclassdef.mmodule.c_name}__{intro_mclassdef.mclass.name.to_cmangle}__{name.to_cmangle}"
1950 # The visibility of the property
1951 var visibility
: MVisibility
1953 # Is the property usable as an initializer?
1954 var is_autoinit
= false is writable
1958 intro_mclassdef
.intro_mproperties
.add
(self)
1959 var model
= intro_mclassdef
.mmodule
.model
1960 model
.mproperties_by_name
.add_one
(name
, self)
1961 model
.mproperties
.add
(self)
1964 # All definitions of the property.
1965 # The first is the introduction,
1966 # The other are redefinitions (in refinements and in subclasses)
1967 var mpropdefs
= new Array[MPROPDEF]
1969 # The definition that introduces the property.
1971 # Warning: such a definition may not exist in the early life of the object.
1972 # In this case, the method will abort.
1973 var intro
: MPROPDEF is noinit
1975 redef fun model
do return intro
.model
1978 redef fun to_s
do return name
1980 # Return the most specific property definitions defined or inherited by a type.
1981 # The selection knows that refinement is stronger than specialization;
1982 # however, in case of conflict more than one property are returned.
1983 # If mtype does not know mproperty then an empty array is returned.
1985 # If you want the really most specific property, then look at `lookup_first_definition`
1987 # REQUIRE: `not mtype.need_anchor` to simplify the API (no `anchor` parameter)
1988 # ENSURE: `not mtype.has_mproperty(mmodule, self) == result.is_empty`
1989 fun lookup_definitions
(mmodule
: MModule, mtype
: MType): Array[MPROPDEF]
1991 assert not mtype
.need_anchor
1992 mtype
= mtype
.undecorate
1994 var cache
= self.lookup_definitions_cache
[mmodule
, mtype
]
1995 if cache
!= null then return cache
1997 #print "select prop {mproperty} for {mtype} in {self}"
1998 # First, select all candidates
1999 var candidates
= new Array[MPROPDEF]
2000 for mpropdef
in self.mpropdefs
do
2001 # If the definition is not imported by the module, then skip
2002 if not mmodule
.in_importation
<= mpropdef
.mclassdef
.mmodule
then continue
2003 # If the definition is not inherited by the type, then skip
2004 if not mtype
.is_subtype
(mmodule
, null, mpropdef
.mclassdef
.bound_mtype
) then continue
2006 candidates
.add
(mpropdef
)
2008 # Fast track for only one candidate
2009 if candidates
.length
<= 1 then
2010 self.lookup_definitions_cache
[mmodule
, mtype
] = candidates
2014 # Second, filter the most specific ones
2015 return select_most_specific
(mmodule
, candidates
)
2018 private var lookup_definitions_cache
= new HashMap2[MModule, MType, Array[MPROPDEF]]
2020 # Return the most specific property definitions inherited by a type.
2021 # The selection knows that refinement is stronger than specialization;
2022 # however, in case of conflict more than one property are returned.
2023 # If mtype does not know mproperty then an empty array is returned.
2025 # If you want the really most specific property, then look at `lookup_next_definition`
2027 # REQUIRE: `not mtype.need_anchor` to simplify the API (no `anchor` parameter)
2028 # ENSURE: `not mtype.has_mproperty(mmodule, self) implies result.is_empty`
2029 fun lookup_super_definitions
(mmodule
: MModule, mtype
: MType): Array[MPROPDEF]
2031 assert not mtype
.need_anchor
2032 mtype
= mtype
.undecorate
2034 # First, select all candidates
2035 var candidates
= new Array[MPROPDEF]
2036 for mpropdef
in self.mpropdefs
do
2037 # If the definition is not imported by the module, then skip
2038 if not mmodule
.in_importation
<= mpropdef
.mclassdef
.mmodule
then continue
2039 # If the definition is not inherited by the type, then skip
2040 if not mtype
.is_subtype
(mmodule
, null, mpropdef
.mclassdef
.bound_mtype
) then continue
2041 # If the definition is defined by the type, then skip (we want the super, so e skip the current)
2042 if mtype
== mpropdef
.mclassdef
.bound_mtype
and mmodule
== mpropdef
.mclassdef
.mmodule
then continue
2044 candidates
.add
(mpropdef
)
2046 # Fast track for only one candidate
2047 if candidates
.length
<= 1 then return candidates
2049 # Second, filter the most specific ones
2050 return select_most_specific
(mmodule
, candidates
)
2053 # Return an array containing olny the most specific property definitions
2054 # This is an helper function for `lookup_definitions` and `lookup_super_definitions`
2055 private fun select_most_specific
(mmodule
: MModule, candidates
: Array[MPROPDEF]): Array[MPROPDEF]
2057 var res
= new Array[MPROPDEF]
2058 for pd1
in candidates
do
2059 var cd1
= pd1
.mclassdef
2062 for pd2
in candidates
do
2063 if pd2
== pd1
then continue # do not compare with self!
2064 var cd2
= pd2
.mclassdef
2066 if c2
.mclass_type
== c1
.mclass_type
then
2067 if cd2
.mmodule
.in_importation
< cd1
.mmodule
then
2068 # cd2 refines cd1; therefore we skip pd1
2072 else if cd2
.bound_mtype
.is_subtype
(mmodule
, null, cd1
.bound_mtype
) and cd2
.bound_mtype
!= cd1
.bound_mtype
then
2073 # cd2 < cd1; therefore we skip pd1
2082 if res
.is_empty
then
2083 print
"All lost! {candidates.join(", ")}"
2084 # FIXME: should be abort!
2089 # Return the most specific definition in the linearization of `mtype`.
2091 # If you want to know the next properties in the linearization,
2092 # look at `MPropDef::lookup_next_definition`.
2094 # FIXME: the linearization is still unspecified
2096 # REQUIRE: `not mtype.need_anchor` to simplify the API (no `anchor` parameter)
2097 # REQUIRE: `mtype.has_mproperty(mmodule, self)`
2098 fun lookup_first_definition
(mmodule
: MModule, mtype
: MType): MPROPDEF
2100 return lookup_all_definitions
(mmodule
, mtype
).first
2103 # Return all definitions in a linearization order
2104 # Most specific first, most general last
2106 # REQUIRE: `not mtype.need_anchor` to simplify the API (no `anchor` parameter)
2107 # REQUIRE: `mtype.has_mproperty(mmodule, self)`
2108 fun lookup_all_definitions
(mmodule
: MModule, mtype
: MType): Array[MPROPDEF]
2110 mtype
= mtype
.undecorate
2112 var cache
= self.lookup_all_definitions_cache
[mmodule
, mtype
]
2113 if cache
!= null then return cache
2115 assert not mtype
.need_anchor
2116 assert mtype
.has_mproperty
(mmodule
, self)
2118 #print "select prop {mproperty} for {mtype} in {self}"
2119 # First, select all candidates
2120 var candidates
= new Array[MPROPDEF]
2121 for mpropdef
in self.mpropdefs
do
2122 # If the definition is not imported by the module, then skip
2123 if not mmodule
.in_importation
<= mpropdef
.mclassdef
.mmodule
then continue
2124 # If the definition is not inherited by the type, then skip
2125 if not mtype
.is_subtype
(mmodule
, null, mpropdef
.mclassdef
.bound_mtype
) then continue
2127 candidates
.add
(mpropdef
)
2129 # Fast track for only one candidate
2130 if candidates
.length
<= 1 then
2131 self.lookup_all_definitions_cache
[mmodule
, mtype
] = candidates
2135 mmodule
.linearize_mpropdefs
(candidates
)
2136 candidates
= candidates
.reversed
2137 self.lookup_all_definitions_cache
[mmodule
, mtype
] = candidates
2141 private var lookup_all_definitions_cache
= new HashMap2[MModule, MType, Array[MPROPDEF]]
2148 redef type MPROPDEF: MMethodDef
2150 # Is the property defined at the top_level of the module?
2151 # Currently such a property are stored in `Object`
2152 var is_toplevel
: Bool = false is writable
2154 # Is the property a constructor?
2155 # Warning, this property can be inherited by subclasses with or without being a constructor
2156 # therefore, you should use `is_init_for` the verify if the property is a legal constructor for a given class
2157 var is_init
: Bool = false is writable
2159 # The constructor is a (the) root init with empty signature but a set of initializers
2160 var is_root_init
: Bool = false is writable
2162 # Is the property a 'new' constructor?
2163 var is_new
: Bool = false is writable
2165 # Is the property a legal constructor for a given class?
2166 # As usual, visibility is not considered.
2167 # FIXME not implemented
2168 fun is_init_for
(mclass
: MClass): Bool
2173 # A specific method that is safe to call on null.
2174 # Currently, only `==`, `!=` and `is_same_instance` are safe
2175 fun is_null_safe
: Bool do return name
== "==" or name
== "!=" or name
== "is_same_instance"
2178 # A global attribute
2182 redef type MPROPDEF: MAttributeDef
2186 # A global virtual type
2187 class MVirtualTypeProp
2190 redef type MPROPDEF: MVirtualTypeDef
2192 # The formal type associated to the virtual type property
2193 var mvirtualtype
= new MVirtualType(self)
2196 # A definition of a property (local property)
2198 # Unlike `MProperty`, a `MPropDef` is a local definition that belong to a
2199 # specific class definition (which belong to a specific module)
2200 abstract class MPropDef
2203 # The associated `MProperty` subclass.
2204 # the two specialization hierarchy are symmetric
2205 type MPROPERTY: MProperty
2208 type MPROPDEF: MPropDef
2210 # The class definition where the property definition is
2211 var mclassdef
: MClassDef
2213 # The associated global property
2214 var mproperty
: MPROPERTY
2216 # The origin of the definition
2217 var location
: Location
2221 mclassdef
.mpropdefs
.add
(self)
2222 mproperty
.mpropdefs
.add
(self)
2223 if mproperty
.intro_mclassdef
== mclassdef
then
2224 assert not isset mproperty
._intro
2225 mproperty
.intro
= self
2227 self.to_s
= "{mclassdef}#{mproperty}"
2230 # Actually the name of the `mproperty`
2231 redef fun name
do return mproperty
.name
2233 # The full-name of mpropdefs combine the information about the `classdef` and the `mproperty`.
2235 # Therefore the combination of identifiers is awful,
2236 # the worst case being
2238 # * a property "p::m::A::x"
2239 # * redefined in a refinement of a class "q::n::B"
2240 # * in a module "r::o"
2241 # * so "r::o#q::n::B#p::m::A::x"
2243 # Fortunately, the full-name is simplified when entities are repeated.
2244 # For the previous case, the simplest form is "p#A#x".
2245 redef var full_name
is lazy
do
2246 var res
= new FlatBuffer
2248 # The first part is the mclassdef. Worst case is "r::o#q::n::B"
2249 res
.append mclassdef
.full_name
2253 if mclassdef
.mclass
== mproperty
.intro_mclassdef
.mclass
then
2254 # intro are unambiguous in a class
2257 # Just try to simplify each part
2258 if mclassdef
.mmodule
.mpackage
!= mproperty
.intro_mclassdef
.mmodule
.mpackage
then
2259 # precise "p::m" only if "p" != "r"
2260 res
.append mproperty
.intro_mclassdef
.mmodule
.full_name
2262 else if mproperty
.visibility
<= private_visibility
then
2263 # Same package ("p"=="q"), but private visibility,
2264 # does the module part ("::m") need to be displayed
2265 if mclassdef
.mmodule
.namespace_for
(mclassdef
.mclass
.visibility
) != mproperty
.intro_mclassdef
.mmodule
.mpackage
then
2267 res
.append mproperty
.intro_mclassdef
.mmodule
.name
2271 if mclassdef
.mclass
!= mproperty
.intro_mclassdef
.mclass
then
2272 # precise "B" only if not the same class than "A"
2273 res
.append mproperty
.intro_mclassdef
.name
2276 # Always use the property name "x"
2277 res
.append mproperty
.name
2282 redef var c_name
is lazy
do
2283 var res
= new FlatBuffer
2284 res
.append mclassdef
.c_name
2286 if mclassdef
.mclass
== mproperty
.intro_mclassdef
.mclass
then
2287 res
.append name
.to_cmangle
2289 if mclassdef
.mmodule
!= mproperty
.intro_mclassdef
.mmodule
then
2290 res
.append mproperty
.intro_mclassdef
.mmodule
.c_name
2293 if mclassdef
.mclass
!= mproperty
.intro_mclassdef
.mclass
then
2294 res
.append mproperty
.intro_mclassdef
.name
.to_cmangle
2297 res
.append mproperty
.name
.to_cmangle
2302 redef fun model
do return mclassdef
.model
2304 # Internal name combining the module, the class and the property
2305 # Example: "mymodule#MyClass#mymethod"
2306 redef var to_s
: String is noinit
2308 # Is self the definition that introduce the property?
2309 fun is_intro
: Bool do return isset mproperty
._intro
and mproperty
.intro
== self
2311 # Return the next definition in linearization of `mtype`.
2313 # This method is used to determine what method is called by a super.
2315 # REQUIRE: `not mtype.need_anchor`
2316 fun lookup_next_definition
(mmodule
: MModule, mtype
: MType): MPROPDEF
2318 assert not mtype
.need_anchor
2320 var mpropdefs
= self.mproperty
.lookup_all_definitions
(mmodule
, mtype
)
2321 var i
= mpropdefs
.iterator
2322 while i
.is_ok
and i
.item
!= self do i
.next
2323 assert has_property
: i
.is_ok
2325 assert has_next_property
: i
.is_ok
2330 # A local definition of a method
2334 redef type MPROPERTY: MMethod
2335 redef type MPROPDEF: MMethodDef
2337 # The signature attached to the property definition
2338 var msignature
: nullable MSignature = null is writable
2340 # The signature attached to the `new` call on a root-init
2341 # This is a concatenation of the signatures of the initializers
2343 # REQUIRE `mproperty.is_root_init == (new_msignature != null)`
2344 var new_msignature
: nullable MSignature = null is writable
2346 # List of initialisers to call in root-inits
2348 # They could be setters or attributes
2350 # REQUIRE `mproperty.is_root_init == (new_msignature != null)`
2351 var initializers
= new Array[MProperty]
2353 # Is the method definition abstract?
2354 var is_abstract
: Bool = false is writable
2356 # Is the method definition intern?
2357 var is_intern
= false is writable
2359 # Is the method definition extern?
2360 var is_extern
= false is writable
2362 # An optional constant value returned in functions.
2364 # Only some specific primitife value are accepted by engines.
2365 # Is used when there is no better implementation available.
2367 # Currently used only for the implementation of the `--define`
2368 # command-line option.
2369 # SEE: module `mixin`.
2370 var constant_value
: nullable Object = null is writable
2373 # A local definition of an attribute
2377 redef type MPROPERTY: MAttribute
2378 redef type MPROPDEF: MAttributeDef
2380 # The static type of the attribute
2381 var static_mtype
: nullable MType = null is writable
2384 # A local definition of a virtual type
2385 class MVirtualTypeDef
2388 redef type MPROPERTY: MVirtualTypeProp
2389 redef type MPROPDEF: MVirtualTypeDef
2391 # The bound of the virtual type
2392 var bound
: nullable MType = null is writable
2394 # Is the bound fixed?
2395 var is_fixed
= false is writable
2402 # * `interface_kind`
2406 # Note this class is basically an enum.
2407 # FIXME: use a real enum once user-defined enums are available
2409 redef var to_s
: String
2411 # Is a constructor required?
2414 # TODO: private init because enumeration.
2416 # Can a class of kind `self` specializes a class of kine `other`?
2417 fun can_specialize
(other
: MClassKind): Bool
2419 if other
== interface_kind
then return true # everybody can specialize interfaces
2420 if self == interface_kind
or self == enum_kind
then
2421 # no other case for interfaces
2423 else if self == extern_kind
then
2424 # only compatible with themselves
2425 return self == other
2426 else if other
== enum_kind
or other
== extern_kind
then
2427 # abstract_kind and concrete_kind are incompatible
2430 # remain only abstract_kind and concrete_kind
2435 # The class kind `abstract`
2436 fun abstract_kind
: MClassKind do return once
new MClassKind("abstract class", true)
2437 # The class kind `concrete`
2438 fun concrete_kind
: MClassKind do return once
new MClassKind("class", true)
2439 # The class kind `interface`
2440 fun interface_kind
: MClassKind do return once
new MClassKind("interface", false)
2441 # The class kind `enum`
2442 fun enum_kind
: MClassKind do return once
new MClassKind("enum", false)
2443 # The class kind `extern`
2444 fun extern_kind
: MClassKind do return once
new MClassKind("extern class", false)