1 # This file is part of NIT ( http://www.nitlanguage.org ).
3 # Copyright 2012 Jean Privat <jean@pryen.org>
5 # Licensed under the Apache License, Version 2.0 (the "License");
6 # you may not use this file except in compliance with the License.
7 # You may obtain a copy of the License at
9 # http://www.apache.org/licenses/LICENSE-2.0
11 # Unless required by applicable law or agreed to in writing, software
12 # distributed under the License is distributed on an "AS IS" BASIS,
13 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 # See the License for the specific language governing permissions and
15 # limitations under the License.
17 # Classes, types and properties
19 # All three concepts are defined in this same module because these are strongly connected:
20 # * types are based on classes
21 # * classes contains properties
22 # * some properties are types (virtual types)
24 # TODO: liearization, extern stuff
25 # FIXME: better handling of the types
31 private import more_collections
35 var mclasses
= new Array[MClass]
37 # All known properties
38 var mproperties
= new Array[MProperty]
40 # Hierarchy of class definition.
42 # Each classdef is associated with its super-classdefs in regard to
43 # its module of definition.
44 var mclassdef_hierarchy
= new POSet[MClassDef]
46 # Class-type hierarchy restricted to the introduction.
48 # The idea is that what is true on introduction is always true whatever
49 # the module considered.
50 # Therefore, this hierarchy is used for a fast positive subtype check.
52 # This poset will evolve in a monotonous way:
53 # * Two non connected nodes will remain unconnected
54 # * New nodes can appear with new edges
55 private var intro_mtype_specialization_hierarchy
= new POSet[MClassType]
57 # Global overlapped class-type hierarchy.
58 # The hierarchy when all modules are combined.
59 # Therefore, this hierarchy is used for a fast negative subtype check.
61 # This poset will evolve in an anarchic way. Loops can even be created.
63 # FIXME decide what to do on loops
64 private var full_mtype_specialization_hierarchy
= new POSet[MClassType]
66 # Collections of classes grouped by their short name
67 private var mclasses_by_name
= new MultiHashMap[String, MClass]
69 # Return all class named `name`.
71 # If such a class does not exist, null is returned
72 # (instead of an empty array)
74 # Visibility or modules are not considered
75 fun get_mclasses_by_name
(name
: String): nullable Array[MClass]
77 if mclasses_by_name
.has_key
(name
) then
78 return mclasses_by_name
[name
]
84 # Collections of properties grouped by their short name
85 private var mproperties_by_name
= new MultiHashMap[String, MProperty]
87 # Return all properties named `name`.
89 # If such a property does not exist, null is returned
90 # (instead of an empty array)
92 # Visibility or modules are not considered
93 fun get_mproperties_by_name
(name
: String): nullable Array[MProperty]
95 if not mproperties_by_name
.has_key
(name
) then
98 return mproperties_by_name
[name
]
103 var null_type
= new MNullType(self)
105 # Build an ordered tree with from `concerns`
106 fun concerns_tree
(mconcerns
: Collection[MConcern]): ConcernsTree do
107 var seen
= new HashSet[MConcern]
108 var res
= new ConcernsTree
110 var todo
= new Array[MConcern]
111 todo
.add_all mconcerns
113 while not todo
.is_empty
do
115 if seen
.has
(c
) then continue
116 var pc
= c
.parent_concern
130 # An OrderedTree that can be easily refined for display purposes
132 super OrderedTree[MConcern]
136 # All the classes introduced in the module
137 var intro_mclasses
= new Array[MClass]
139 # All the class definitions of the module
140 # (introduction and refinement)
141 var mclassdefs
= new Array[MClassDef]
143 # Does the current module has a given class `mclass`?
144 # Return true if the mmodule introduces, refines or imports a class.
145 # Visibility is not considered.
146 fun has_mclass
(mclass
: MClass): Bool
148 return self.in_importation
<= mclass
.intro_mmodule
151 # Full hierarchy of introduced ans imported classes.
153 # Create a new hierarchy got by flattening the classes for the module
154 # and its imported modules.
155 # Visibility is not considered.
157 # Note: this function is expensive and is usually used for the main
158 # module of a program only. Do not use it to do you own subtype
160 fun flatten_mclass_hierarchy
: POSet[MClass]
162 var res
= self.flatten_mclass_hierarchy_cache
163 if res
!= null then return res
164 res
= new POSet[MClass]
165 for m
in self.in_importation
.greaters
do
166 for cd
in m
.mclassdefs
do
169 for s
in cd
.supertypes
do
170 res
.add_edge
(c
, s
.mclass
)
174 self.flatten_mclass_hierarchy_cache
= res
178 # Sort a given array of classes using the linearization order of the module
179 # The most general is first, the most specific is last
180 fun linearize_mclasses
(mclasses
: Array[MClass])
182 self.flatten_mclass_hierarchy
.sort
(mclasses
)
185 # Sort a given array of class definitions using the linearization order of the module
186 # the refinement link is stronger than the specialisation link
187 # The most general is first, the most specific is last
188 fun linearize_mclassdefs
(mclassdefs
: Array[MClassDef])
190 var sorter
= new MClassDefSorter(self)
191 sorter
.sort
(mclassdefs
)
194 # Sort a given array of property definitions using the linearization order of the module
195 # the refinement link is stronger than the specialisation link
196 # The most general is first, the most specific is last
197 fun linearize_mpropdefs
(mpropdefs
: Array[MPropDef])
199 var sorter
= new MPropDefSorter(self)
200 sorter
.sort
(mpropdefs
)
203 private var flatten_mclass_hierarchy_cache
: nullable POSet[MClass] = null
205 # The primitive type `Object`, the root of the class hierarchy
206 fun object_type
: MClassType
208 var res
= self.object_type_cache
209 if res
!= null then return res
210 res
= self.get_primitive_class
("Object").mclass_type
211 self.object_type_cache
= res
215 private var object_type_cache
: nullable MClassType
217 # The type `Pointer`, super class to all extern classes
218 var pointer_type
: MClassType = self.get_primitive_class
("Pointer").mclass_type
is lazy
220 # The primitive type `Bool`
221 fun bool_type
: MClassType
223 var res
= self.bool_type_cache
224 if res
!= null then return res
225 res
= self.get_primitive_class
("Bool").mclass_type
226 self.bool_type_cache
= res
230 private var bool_type_cache
: nullable MClassType
232 # The primitive type `Sys`, the main type of the program, if any
233 fun sys_type
: nullable MClassType
235 var clas
= self.model
.get_mclasses_by_name
("Sys")
236 if clas
== null then return null
237 return get_primitive_class
("Sys").mclass_type
240 # The primitive type `Finalizable`
241 # Used to tag classes that need to be finalized.
242 fun finalizable_type
: nullable MClassType
244 var clas
= self.model
.get_mclasses_by_name
("Finalizable")
245 if clas
== null then return null
246 return get_primitive_class
("Finalizable").mclass_type
249 # Force to get the primitive class named `name` or abort
250 fun get_primitive_class
(name
: String): MClass
252 var cla
= self.model
.get_mclasses_by_name
(name
)
254 if name
== "Bool" and self.model
.get_mclasses_by_name
("Object") != null then
255 # Bool is injected because it is needed by engine to code the result
256 # of the implicit casts.
257 var c
= new MClass(self, name
, null, enum_kind
, public_visibility
)
258 var cladef
= new MClassDef(self, c
.mclass_type
, new Location(null, 0,0,0,0))
259 cladef
.set_supertypes
([object_type
])
260 cladef
.add_in_hierarchy
263 print
("Fatal Error: no primitive class {name}")
266 if cla
.length
!= 1 then
267 var msg
= "Fatal Error: more than one primitive class {name}:"
268 for c
in cla
do msg
+= " {c.full_name}"
275 # Try to get the primitive method named `name` on the type `recv`
276 fun try_get_primitive_method
(name
: String, recv
: MClass): nullable MMethod
278 var props
= self.model
.get_mproperties_by_name
(name
)
279 if props
== null then return null
280 var res
: nullable MMethod = null
281 for mprop
in props
do
282 assert mprop
isa MMethod
283 var intro
= mprop
.intro_mclassdef
284 for mclassdef
in recv
.mclassdefs
do
285 if not self.in_importation
.greaters
.has
(mclassdef
.mmodule
) then continue
286 if not mclassdef
.in_hierarchy
.greaters
.has
(intro
) then continue
289 else if res
!= mprop
then
290 print
("Fatal Error: ambigous property name '{name}'; conflict between {mprop.full_name} and {res.full_name}")
299 private class MClassDefSorter
301 redef type COMPARED: MClassDef
303 redef fun compare
(a
, b
)
307 if ca
!= cb
then return mmodule
.flatten_mclass_hierarchy
.compare
(ca
, cb
)
308 return mmodule
.model
.mclassdef_hierarchy
.compare
(a
, b
)
312 private class MPropDefSorter
314 redef type COMPARED: MPropDef
316 redef fun compare
(pa
, pb
)
322 if ca
!= cb
then return mmodule
.flatten_mclass_hierarchy
.compare
(ca
, cb
)
323 return mmodule
.model
.mclassdef_hierarchy
.compare
(a
, b
)
329 # `MClass` are global to the model; it means that a `MClass` is not bound to a
330 # specific `MModule`.
332 # This characteristic helps the reasoning about classes in a program since a
333 # single `MClass` object always denote the same class.
335 # The drawback is that classes (`MClass`) contain almost nothing by themselves.
336 # These do not really have properties nor belong to a hierarchy since the property and the
337 # hierarchy of a class depends of the refinement in the modules.
339 # Most services on classes require the precision of a module, and no one can asks what are
340 # the super-classes of a class nor what are properties of a class without precising what is
341 # the module considered.
343 # For instance, during the typing of a source-file, the module considered is the module of the file.
344 # eg. the question *is the method `foo` exists in the class `Bar`?* must be reformulated into
345 # *is the method `foo` exists in the class `Bar` in the current module?*
347 # During some global analysis, the module considered may be the main module of the program.
351 # The module that introduce the class
352 # While classes are not bound to a specific module,
353 # the introducing module is used for naming an visibility
354 var intro_mmodule
: MModule
356 # The short name of the class
357 # In Nit, the name of a class cannot evolve in refinements
358 redef var name
: String
360 # The canonical name of the class
362 # It is the name of the class prefixed by the full_name of the `intro_mmodule`
363 # Example: `"owner::module::MyClass"`
364 redef var full_name
is lazy
do
365 return "{self.intro_mmodule.namespace_for(visibility)}::{name}"
368 redef var c_name
is lazy
do
369 return "{intro_mmodule.c_namespace_for(visibility)}__{name.to_cmangle}"
372 # The number of generic formal parameters
373 # 0 if the class is not generic
374 var arity
: Int is noinit
376 # Each generic formal parameters in order.
377 # is empty if the class is not generic
378 var mparameters
= new Array[MParameterType]
380 # Initialize `mparameters` from their names.
381 protected fun setup_parameter_names
(parameter_names
: nullable Array[String]) is
384 if parameter_names
== null then
387 self.arity
= parameter_names
.length
390 # Create the formal parameter types
392 assert parameter_names
!= null
393 var mparametertypes
= new Array[MParameterType]
394 for i
in [0..arity
[ do
395 var mparametertype
= new MParameterType(self, i
, parameter_names
[i
])
396 mparametertypes
.add
(mparametertype
)
398 self.mparameters
= mparametertypes
399 var mclass_type
= new MGenericType(self, mparametertypes
)
400 self.mclass_type
= mclass_type
401 self.get_mtype_cache
[mparametertypes
] = mclass_type
403 self.mclass_type
= new MClassType(self)
407 # The kind of the class (interface, abstract class, etc.)
408 # In Nit, the kind of a class cannot evolve in refinements
411 # The visibility of the class
412 # In Nit, the visibility of a class cannot evolve in refinements
413 var visibility
: MVisibility
417 intro_mmodule
.intro_mclasses
.add
(self)
418 var model
= intro_mmodule
.model
419 model
.mclasses_by_name
.add_one
(name
, self)
420 model
.mclasses
.add
(self)
423 redef fun model
do return intro_mmodule
.model
425 # All class definitions (introduction and refinements)
426 var mclassdefs
= new Array[MClassDef]
429 redef fun to_s
do return self.name
431 # The definition that introduces the class.
433 # Warning: such a definition may not exist in the early life of the object.
434 # In this case, the method will abort.
435 var intro
: MClassDef is noinit
437 # Return the class `self` in the class hierarchy of the module `mmodule`.
439 # SEE: `MModule::flatten_mclass_hierarchy`
440 # REQUIRE: `mmodule.has_mclass(self)`
441 fun in_hierarchy
(mmodule
: MModule): POSetElement[MClass]
443 return mmodule
.flatten_mclass_hierarchy
[self]
446 # The principal static type of the class.
448 # For non-generic class, mclass_type is the only `MClassType` based
451 # For a generic class, the arguments are the formal parameters.
452 # i.e.: for the class Array[E:Object], the `mclass_type` is Array[E].
453 # If you want Array[Object] the see `MClassDef::bound_mtype`
455 # For generic classes, the mclass_type is also the way to get a formal
456 # generic parameter type.
458 # To get other types based on a generic class, see `get_mtype`.
460 # ENSURE: `mclass_type.mclass == self`
461 var mclass_type
: MClassType is noinit
463 # Return a generic type based on the class
464 # Is the class is not generic, then the result is `mclass_type`
466 # REQUIRE: `mtype_arguments.length == self.arity`
467 fun get_mtype
(mtype_arguments
: Array[MType]): MClassType
469 assert mtype_arguments
.length
== self.arity
470 if self.arity
== 0 then return self.mclass_type
471 var res
= get_mtype_cache
.get_or_null
(mtype_arguments
)
472 if res
!= null then return res
473 res
= new MGenericType(self, mtype_arguments
)
474 self.get_mtype_cache
[mtype_arguments
.to_a
] = res
478 private var get_mtype_cache
= new HashMap[Array[MType], MGenericType]
482 # A definition (an introduction or a refinement) of a class in a module
484 # A `MClassDef` is associated with an explicit (or almost) definition of a
485 # class. Unlike `MClass`, a `MClassDef` is a local definition that belong to
486 # a specific class and a specific module, and contains declarations like super-classes
489 # It is the class definitions that are the backbone of most things in the model:
490 # ClassDefs are defined with regard with other classdefs.
491 # Refinement and specialization are combined to produce a big poset called the `Model::mclassdef_hierarchy`.
493 # Moreover, the extension and the intention of types is defined by looking at the MClassDefs.
497 # The module where the definition is
500 # The associated `MClass`
501 var mclass
: MClass is noinit
503 # The bounded type associated to the mclassdef
505 # For a non-generic class, `bound_mtype` and `mclass.mclass_type`
509 # For the classdef Array[E: Object], the bound_mtype is Array[Object].
510 # If you want Array[E], then see `mclass.mclass_type`
512 # ENSURE: `bound_mtype.mclass == self.mclass`
513 var bound_mtype
: MClassType
515 # The origin of the definition
516 var location
: Location
518 # Internal name combining the module and the class
519 # Example: "mymodule#MyClass"
520 redef var to_s
: String is noinit
524 self.mclass
= bound_mtype
.mclass
525 mmodule
.mclassdefs
.add
(self)
526 mclass
.mclassdefs
.add
(self)
527 if mclass
.intro_mmodule
== mmodule
then
528 assert not isset mclass
._intro
531 self.to_s
= "{mmodule}#{mclass}"
534 # Actually the name of the `mclass`
535 redef fun name
do return mclass
.name
537 # The module and class name separated by a '#'.
539 # The short-name of the class is used for introduction.
540 # Example: "my_module#MyClass"
542 # The full-name of the class is used for refinement.
543 # Example: "my_module#intro_module::MyClass"
544 redef var full_name
is lazy
do
547 # private gives 'p::m#A'
548 return "{mmodule.namespace_for(mclass.visibility)}#{mclass.name}"
549 else if mclass
.intro_mmodule
.mproject
!= mmodule
.mproject
then
550 # public gives 'q::n#p::A'
551 # private gives 'q::n#p::m::A'
552 return "{mmodule.full_name}#{mclass.full_name}"
553 else if mclass
.visibility
> private_visibility
then
554 # public gives 'p::n#A'
555 return "{mmodule.full_name}#{mclass.name}"
557 # private gives 'p::n#::m::A' (redundant p is omitted)
558 return "{mmodule.full_name}#::{mclass.intro_mmodule.name}::{mclass.name}"
562 redef var c_name
is lazy
do
564 return "{mmodule.c_namespace_for(mclass.visibility)}___{mclass.c_name}"
565 else if mclass
.intro_mmodule
.mproject
== mmodule
.mproject
and mclass
.visibility
> private_visibility
then
566 return "{mmodule.c_name}___{mclass.name.to_cmangle}"
568 return "{mmodule.c_name}___{mclass.c_name}"
572 redef fun model
do return mmodule
.model
574 # All declared super-types
575 # FIXME: quite ugly but not better idea yet
576 var supertypes
= new Array[MClassType]
578 # Register some super-types for the class (ie "super SomeType")
580 # The hierarchy must not already be set
581 # REQUIRE: `self.in_hierarchy == null`
582 fun set_supertypes
(supertypes
: Array[MClassType])
584 assert unique_invocation
: self.in_hierarchy
== null
585 var mmodule
= self.mmodule
586 var model
= mmodule
.model
587 var mtype
= self.bound_mtype
589 for supertype
in supertypes
do
590 self.supertypes
.add
(supertype
)
592 # Register in full_type_specialization_hierarchy
593 model
.full_mtype_specialization_hierarchy
.add_edge
(mtype
, supertype
)
594 # Register in intro_type_specialization_hierarchy
595 if mclass
.intro_mmodule
== mmodule
and supertype
.mclass
.intro_mmodule
== mmodule
then
596 model
.intro_mtype_specialization_hierarchy
.add_edge
(mtype
, supertype
)
602 # Collect the super-types (set by set_supertypes) to build the hierarchy
604 # This function can only invoked once by class
605 # REQUIRE: `self.in_hierarchy == null`
606 # ENSURE: `self.in_hierarchy != null`
609 assert unique_invocation
: self.in_hierarchy
== null
610 var model
= mmodule
.model
611 var res
= model
.mclassdef_hierarchy
.add_node
(self)
612 self.in_hierarchy
= res
613 var mtype
= self.bound_mtype
615 # Here we need to connect the mclassdef to its pairs in the mclassdef_hierarchy
616 # The simpliest way is to attach it to collect_mclassdefs
617 for mclassdef
in mtype
.collect_mclassdefs
(mmodule
) do
618 res
.poset
.add_edge
(self, mclassdef
)
622 # The view of the class definition in `mclassdef_hierarchy`
623 var in_hierarchy
: nullable POSetElement[MClassDef] = null
625 # Is the definition the one that introduced `mclass`?
626 fun is_intro
: Bool do return mclass
.intro
== self
628 # All properties introduced by the classdef
629 var intro_mproperties
= new Array[MProperty]
631 # All property definitions in the class (introductions and redefinitions)
632 var mpropdefs
= new Array[MPropDef]
635 # A global static type
637 # MType are global to the model; it means that a `MType` is not bound to a
638 # specific `MModule`.
639 # This characteristic helps the reasoning about static types in a program
640 # since a single `MType` object always denote the same type.
642 # However, because a `MType` is global, it does not really have properties
643 # nor have subtypes to a hierarchy since the property and the class hierarchy
644 # depends of a module.
645 # Moreover, virtual types an formal generic parameter types also depends on
646 # a receiver to have sense.
648 # Therefore, most method of the types require a module and an anchor.
649 # The module is used to know what are the classes and the specialization
651 # The anchor is used to know what is the bound of the virtual types and formal
652 # generic parameter types.
654 # MType are not directly usable to get properties. See the `anchor_to` method
655 # and the `MClassType` class.
657 # FIXME: the order of the parameters is not the best. We mus pick on from:
658 # * foo(mmodule, anchor, othertype)
659 # * foo(othertype, anchor, mmodule)
660 # * foo(anchor, mmodule, othertype)
661 # * foo(othertype, mmodule, anchor)
665 redef fun name
do return to_s
667 # Return true if `self` is an subtype of `sup`.
668 # The typing is done using the standard typing policy of Nit.
670 # REQUIRE: `anchor == null implies not self.need_anchor and not sup.need_anchor`
671 # REQUIRE: `anchor != null implies self.can_resolve_for(anchor, null, mmodule) and sup.can_resolve_for(anchor, null, mmodule)`
672 fun is_subtype
(mmodule
: MModule, anchor
: nullable MClassType, sup
: MType): Bool
675 if sub
== sup
then return true
677 #print "1.is {sub} a {sup}? ===="
679 if anchor
== null then
680 assert not sub
.need_anchor
681 assert not sup
.need_anchor
683 # First, resolve the formal types to the simplest equivalent forms in the receiver
684 assert sub
.can_resolve_for
(anchor
, null, mmodule
)
685 sub
= sub
.lookup_fixed
(mmodule
, anchor
)
686 assert sup
.can_resolve_for
(anchor
, null, mmodule
)
687 sup
= sup
.lookup_fixed
(mmodule
, anchor
)
690 # Does `sup` accept null or not?
691 # Discard the nullable marker if it exists
692 var sup_accept_null
= false
693 if sup
isa MNullableType then
694 sup_accept_null
= true
696 else if sup
isa MNullType then
697 sup_accept_null
= true
700 # Can `sub` provide null or not?
701 # Thus we can match with `sup_accept_null`
702 # Also discard the nullable marker if it exists
703 if sub
isa MNullableType then
704 if not sup_accept_null
then return false
706 else if sub
isa MNullType then
707 return sup_accept_null
709 # Now the case of direct null and nullable is over.
711 # If `sub` is a formal type, then it is accepted if its bound is accepted
712 while sub
isa MParameterType or sub
isa MVirtualType do
713 #print "3.is {sub} a {sup}?"
715 # A unfixed formal type can only accept itself
716 if sub
== sup
then return true
718 assert anchor
!= null
719 sub
= sub
.lookup_bound
(mmodule
, anchor
)
721 #print "3.is {sub} a {sup}?"
723 # Manage the second layer of null/nullable
724 if sub
isa MNullableType then
725 if not sup_accept_null
then return false
727 else if sub
isa MNullType then
728 return sup_accept_null
731 #print "4.is {sub} a {sup}? <- no more resolution"
733 assert sub
isa MClassType # It is the only remaining type
735 # A unfixed formal type can only accept itself
736 if sup
isa MParameterType or sup
isa MVirtualType then
740 if sup
isa MNullType then
741 # `sup` accepts only null
745 assert sup
isa MClassType # It is the only remaining type
747 # Now both are MClassType, we need to dig
749 if sub
== sup
then return true
751 if anchor
== null then anchor
= sub
# UGLY: any anchor will work
752 var resolved_sub
= sub
.anchor_to
(mmodule
, anchor
)
753 var res
= resolved_sub
.collect_mclasses
(mmodule
).has
(sup
.mclass
)
754 if res
== false then return false
755 if not sup
isa MGenericType then return true
756 var sub2
= sub
.supertype_to
(mmodule
, anchor
, sup
.mclass
)
757 assert sub2
.mclass
== sup
.mclass
758 for i
in [0..sup
.mclass
.arity
[ do
759 var sub_arg
= sub2
.arguments
[i
]
760 var sup_arg
= sup
.arguments
[i
]
761 res
= sub_arg
.is_subtype
(mmodule
, anchor
, sup_arg
)
762 if res
== false then return false
767 # The base class type on which self is based
769 # This base type is used to get property (an internally to perform
770 # unsafe type comparison).
772 # Beware: some types (like null) are not based on a class thus this
775 # Basically, this function transform the virtual types and parameter
776 # types to their bounds.
781 # class B super A end
783 # class Y super X end
792 # Map[T,U] anchor_to H #-> Map[B,Y]
794 # Explanation of the example:
795 # In H, T is set to B, because "H super G[B]", and U is bound to Y,
796 # because "redef type U: Y". Therefore, Map[T, U] is bound to
799 # ENSURE: `not self.need_anchor implies result == self`
800 # ENSURE: `not result.need_anchor`
801 fun anchor_to
(mmodule
: MModule, anchor
: MClassType): MType
803 if not need_anchor
then return self
804 assert not anchor
.need_anchor
805 # Just resolve to the anchor and clear all the virtual types
806 var res
= self.resolve_for
(anchor
, null, mmodule
, true)
807 assert not res
.need_anchor
811 # Does `self` contain a virtual type or a formal generic parameter type?
812 # In order to remove those types, you usually want to use `anchor_to`.
813 fun need_anchor
: Bool do return true
815 # Return the supertype when adapted to a class.
817 # In Nit, for each super-class of a type, there is a equivalent super-type.
823 # class H[V] super G[V, Bool] end
825 # H[Int] supertype_to G #-> G[Int, Bool]
828 # REQUIRE: `super_mclass` is a super-class of `self`
829 # REQUIRE: `self.need_anchor implies anchor != null and self.can_resolve_for(anchor, null, mmodule)`
830 # ENSURE: `result.mclass = super_mclass`
831 fun supertype_to
(mmodule
: MModule, anchor
: nullable MClassType, super_mclass
: MClass): MClassType
833 if super_mclass
.arity
== 0 then return super_mclass
.mclass_type
834 if self isa MClassType and self.mclass
== super_mclass
then return self
836 if self.need_anchor
then
837 assert anchor
!= null
838 resolved_self
= self.anchor_to
(mmodule
, anchor
)
842 var supertypes
= resolved_self
.collect_mtypes
(mmodule
)
843 for supertype
in supertypes
do
844 if supertype
.mclass
== super_mclass
then
845 # FIXME: Here, we stop on the first goal. Should we check others and detect inconsistencies?
846 return supertype
.resolve_for
(self, anchor
, mmodule
, false)
852 # Replace formals generic types in self with resolved values in `mtype`
853 # If `cleanup_virtual` is true, then virtual types are also replaced
856 # This function returns self if `need_anchor` is false.
862 # class H[F] super G[F] end
866 # * Array[E].resolve_for(H[Int]) #-> Array[Int]
867 # * Array[E].resolve_for(G[Z], X[Int]) #-> Array[Z]
869 # Explanation of the example:
870 # * Array[E].need_anchor is true because there is a formal generic parameter type E
871 # * E makes sense for H[Int] because E is a formal parameter of G and H specialize G
872 # * Since "H[F] super G[F]", E is in fact F for H
873 # * More specifically, in H[Int], E is Int
874 # * So, in H[Int], Array[E] is Array[Int]
876 # This function is mainly used to inherit a signature.
877 # Because, unlike `anchor_to`, we do not want a full resolution of
878 # a type but only an adapted version of it.
884 # fun foo(e:E):E is abstract
886 # class B super A[Int] end
889 # The signature on foo is (e: E): E
890 # If we resolve the signature for B, we get (e:Int):Int
896 # fun foo(e:E):E is abstract
900 # fun bar do a.foo(x) # <- x is here
904 # The first question is: is foo available on `a`?
906 # The static type of a is `A[Array[F]]`, that is an open type.
907 # in order to find a method `foo`, whe must look at a resolved type.
909 # A[Array[F]].anchor_to(C[nullable Object]) #-> A[Array[nullable Object]]
911 # the method `foo` exists in `A[Array[nullable Object]]`, therefore `foo` exists for `a`.
913 # The next question is: what is the accepted types for `x`?
915 # the signature of `foo` is `foo(e:E)`, thus we must resolve the type E
917 # E.resolve_for(A[Array[F]],C[nullable Object]) #-> Array[F]
919 # The resolution can be done because `E` make sense for the class A (see `can_resolve_for`)
921 # FIXME: the parameter `cleanup_virtual` is just a bad idea, but having
922 # two function instead of one seems also to be a bad idea.
924 # REQUIRE: `can_resolve_for(mtype, anchor, mmodule)`
925 # ENSURE: `not self.need_anchor implies result == self`
926 fun resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule, cleanup_virtual
: Bool): MType is abstract
928 # Resolve formal type to its verbatim bound.
929 # If the type is not formal, just return self
931 # The result is returned exactly as declared in the "type" property (verbatim).
932 # So it could be another formal type.
934 # In case of conflict, the method aborts.
935 fun lookup_bound
(mmodule
: MModule, resolved_receiver
: MType): MType do return self
937 # Resolve the formal type to its simplest equivalent form.
939 # Formal types are either free or fixed.
940 # When it is fixed, it means that it is equivalent with a simpler type.
941 # When a formal type is free, it means that it is only equivalent with itself.
942 # This method return the most simple equivalent type of `self`.
944 # This method is mainly used for subtype test in order to sanely compare fixed.
946 # By default, return self.
947 # See the redefinitions for specific behavior in each kind of type.
948 fun lookup_fixed
(mmodule
: MModule, resolved_receiver
: MType): MType do return self
950 # Can the type be resolved?
952 # In order to resolve open types, the formal types must make sence.
962 # E.can_resolve_for(A[Int]) #-> true, E make sense in A
964 # E.can_resolve_for(B[Int]) #-> false, E does not make sense in B
966 # B[E].can_resolve_for(A[F], B[Object]) #-> true,
967 # # B[E] is a red hearing only the E is important,
968 # # E make sense in A
971 # REQUIRE: `anchor != null implies not anchor.need_anchor`
972 # REQUIRE: `mtype.need_anchor implies anchor != null and mtype.can_resolve_for(anchor, null, mmodule)`
973 # ENSURE: `not self.need_anchor implies result == true`
974 fun can_resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule): Bool is abstract
976 # Return the nullable version of the type
977 # If the type is already nullable then self is returned
978 fun as_nullable
: MType
980 var res
= self.as_nullable_cache
981 if res
!= null then return res
982 res
= new MNullableType(self)
983 self.as_nullable_cache
= res
987 # Return the not nullable version of the type
988 # Is the type is already not nullable, then self is returned.
990 # Note: this just remove the `nullable` notation, but the result can still contains null.
991 # For instance if `self isa MNullType` or self is a formal type bounded by a nullable type.
992 fun as_notnullable
: MType
997 private var as_nullable_cache
: nullable MType = null
1000 # The depth of the type seen as a tree.
1007 # Formal types have a depth of 1.
1013 # The length of the type seen as a tree.
1020 # Formal types have a length of 1.
1026 # Compute all the classdefs inherited/imported.
1027 # The returned set contains:
1028 # * the class definitions from `mmodule` and its imported modules
1029 # * the class definitions of this type and its super-types
1031 # This function is used mainly internally.
1033 # REQUIRE: `not self.need_anchor`
1034 fun collect_mclassdefs
(mmodule
: MModule): Set[MClassDef] is abstract
1036 # Compute all the super-classes.
1037 # This function is used mainly internally.
1039 # REQUIRE: `not self.need_anchor`
1040 fun collect_mclasses
(mmodule
: MModule): Set[MClass] is abstract
1042 # Compute all the declared super-types.
1043 # Super-types are returned as declared in the classdefs (verbatim).
1044 # This function is used mainly internally.
1046 # REQUIRE: `not self.need_anchor`
1047 fun collect_mtypes
(mmodule
: MModule): Set[MClassType] is abstract
1049 # Is the property in self for a given module
1050 # This method does not filter visibility or whatever
1052 # REQUIRE: `not self.need_anchor`
1053 fun has_mproperty
(mmodule
: MModule, mproperty
: MProperty): Bool
1055 assert not self.need_anchor
1056 return self.collect_mclassdefs
(mmodule
).has
(mproperty
.intro_mclassdef
)
1060 # A type based on a class.
1062 # `MClassType` have properties (see `has_mproperty`).
1066 # The associated class
1069 redef fun model
do return self.mclass
.intro_mmodule
.model
1071 # TODO: private init because strongly bounded to its mclass. see `mclass.mclass_type`
1073 # The formal arguments of the type
1074 # ENSURE: `result.length == self.mclass.arity`
1075 var arguments
= new Array[MType]
1077 redef fun to_s
do return mclass
.to_s
1079 redef fun full_name
do return mclass
.full_name
1081 redef fun c_name
do return mclass
.c_name
1083 redef fun need_anchor
do return false
1085 redef fun anchor_to
(mmodule
: MModule, anchor
: MClassType): MClassType
1087 return super.as(MClassType)
1090 redef fun resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule, cleanup_virtual
: Bool): MClassType do return self
1092 redef fun can_resolve_for
(mtype
, anchor
, mmodule
) do return true
1094 redef fun collect_mclassdefs
(mmodule
)
1096 assert not self.need_anchor
1097 var cache
= self.collect_mclassdefs_cache
1098 if not cache
.has_key
(mmodule
) then
1099 self.collect_things
(mmodule
)
1101 return cache
[mmodule
]
1104 redef fun collect_mclasses
(mmodule
)
1106 if collect_mclasses_last_module
== mmodule
then return collect_mclasses_last_module_cache
1107 assert not self.need_anchor
1108 var cache
= self.collect_mclasses_cache
1109 if not cache
.has_key
(mmodule
) then
1110 self.collect_things
(mmodule
)
1112 var res
= cache
[mmodule
]
1113 collect_mclasses_last_module
= mmodule
1114 collect_mclasses_last_module_cache
= res
1118 private var collect_mclasses_last_module
: nullable MModule = null
1119 private var collect_mclasses_last_module_cache
: Set[MClass] is noinit
1121 redef fun collect_mtypes
(mmodule
)
1123 assert not self.need_anchor
1124 var cache
= self.collect_mtypes_cache
1125 if not cache
.has_key
(mmodule
) then
1126 self.collect_things
(mmodule
)
1128 return cache
[mmodule
]
1131 # common implementation for `collect_mclassdefs`, `collect_mclasses`, and `collect_mtypes`.
1132 private fun collect_things
(mmodule
: MModule)
1134 var res
= new HashSet[MClassDef]
1135 var seen
= new HashSet[MClass]
1136 var types
= new HashSet[MClassType]
1137 seen
.add
(self.mclass
)
1138 var todo
= [self.mclass
]
1139 while not todo
.is_empty
do
1140 var mclass
= todo
.pop
1141 #print "process {mclass}"
1142 for mclassdef
in mclass
.mclassdefs
do
1143 if not mmodule
.in_importation
<= mclassdef
.mmodule
then continue
1144 #print " process {mclassdef}"
1146 for supertype
in mclassdef
.supertypes
do
1147 types
.add
(supertype
)
1148 var superclass
= supertype
.mclass
1149 if seen
.has
(superclass
) then continue
1150 #print " add {superclass}"
1151 seen
.add
(superclass
)
1152 todo
.add
(superclass
)
1156 collect_mclassdefs_cache
[mmodule
] = res
1157 collect_mclasses_cache
[mmodule
] = seen
1158 collect_mtypes_cache
[mmodule
] = types
1161 private var collect_mclassdefs_cache
= new HashMap[MModule, Set[MClassDef]]
1162 private var collect_mclasses_cache
= new HashMap[MModule, Set[MClass]]
1163 private var collect_mtypes_cache
= new HashMap[MModule, Set[MClassType]]
1167 # A type based on a generic class.
1168 # A generic type a just a class with additional formal generic arguments.
1174 # TODO: private init because strongly bounded to its mclass. see `mclass.get_mtype`
1178 assert self.mclass
.arity
== arguments
.length
1180 self.need_anchor
= false
1181 for t
in arguments
do
1182 if t
.need_anchor
then
1183 self.need_anchor
= true
1188 self.to_s
= "{mclass}[{arguments.join(", ")}]"
1191 # The short-name of the class, then the full-name of each type arguments within brackets.
1192 # Example: `"Map[String, List[Int]]"`
1193 redef var to_s
: String is noinit
1195 # The full-name of the class, then the full-name of each type arguments within brackets.
1196 # Example: `"standard::Map[standard::String, standard::List[standard::Int]]"`
1197 redef var full_name
is lazy
do
1198 var args
= new Array[String]
1199 for t
in arguments
do
1200 args
.add t
.full_name
1202 return "{mclass.full_name}[{args.join(", ")}]}"
1205 redef var c_name
is lazy
do
1206 var res
= mclass
.c_name
1207 # Note: because the arity is known, a prefix notation is enough
1208 for t
in arguments
do
1215 redef var need_anchor
: Bool is noinit
1217 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1219 if not need_anchor
then return self
1220 assert can_resolve_for
(mtype
, anchor
, mmodule
)
1221 var types
= new Array[MType]
1222 for t
in arguments
do
1223 types
.add
(t
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
))
1225 return mclass
.get_mtype
(types
)
1228 redef fun can_resolve_for
(mtype
, anchor
, mmodule
)
1230 if not need_anchor
then return true
1231 for t
in arguments
do
1232 if not t
.can_resolve_for
(mtype
, anchor
, mmodule
) then return false
1241 for a
in self.arguments
do
1243 if d
> dmax
then dmax
= d
1251 for a
in self.arguments
do
1258 # A virtual formal type.
1262 # The property associated with the type.
1263 # Its the definitions of this property that determine the bound or the virtual type.
1264 var mproperty
: MVirtualTypeProp
1266 redef fun model
do return self.mproperty
.intro_mclassdef
.mmodule
.model
1268 redef fun lookup_bound
(mmodule
: MModule, resolved_receiver
: MType): MType
1270 return lookup_single_definition
(mmodule
, resolved_receiver
).bound
.as(not null)
1273 private fun lookup_single_definition
(mmodule
: MModule, resolved_receiver
: MType): MVirtualTypeDef
1275 assert not resolved_receiver
.need_anchor
1276 var props
= self.mproperty
.lookup_definitions
(mmodule
, resolved_receiver
)
1277 if props
.is_empty
then
1279 else if props
.length
== 1 then
1282 var types
= new ArraySet[MType]
1283 var res
= props
.first
1285 types
.add
(p
.bound
.as(not null))
1286 if not res
.is_fixed
then res
= p
1288 if types
.length
== 1 then
1294 # A VT is fixed when:
1295 # * the VT is (re-)defined with the annotation `is fixed`
1296 # * the VT is (indirectly) bound to an enum class (see `enum_kind`) since there is no subtype possible
1297 # * the receiver is an enum class since there is no subtype possible
1298 redef fun lookup_fixed
(mmodule
: MModule, resolved_receiver
: MType): MType
1300 assert not resolved_receiver
.need_anchor
1301 resolved_receiver
= resolved_receiver
.as_notnullable
1302 assert resolved_receiver
isa MClassType # It is the only remaining type
1304 var prop
= lookup_single_definition
(mmodule
, resolved_receiver
)
1305 var res
= prop
.bound
.as(not null)
1307 # Recursively lookup the fixed result
1308 res
= res
.lookup_fixed
(mmodule
, resolved_receiver
)
1310 # 1. For a fixed VT, return the resolved bound
1311 if prop
.is_fixed
then return res
1313 # 2. For a enum boud, return the bound
1314 if res
isa MClassType and res
.mclass
.kind
== enum_kind
then return res
1316 # 3. for a enum receiver return the bound
1317 if resolved_receiver
.mclass
.kind
== enum_kind
then return res
1322 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1324 if not cleanup_virtual
then return self
1325 assert can_resolve_for
(mtype
, anchor
, mmodule
)
1326 # self is a virtual type declared (or inherited) in mtype
1327 # The point of the function it to get the bound of the virtual type that make sense for mtype
1328 # But because mtype is maybe a virtual/formal type, we need to get a real receiver first
1329 #print "{class_name}: {self}/{mtype}/{anchor}?"
1330 var resolved_receiver
1331 if mtype
.need_anchor
then
1332 assert anchor
!= null
1333 resolved_receiver
= mtype
.resolve_for
(anchor
, null, mmodule
, true)
1335 resolved_receiver
= mtype
1337 # Now, we can get the bound
1338 var verbatim_bound
= lookup_bound
(mmodule
, resolved_receiver
)
1339 # The bound is exactly as declared in the "type" property, so we must resolve it again
1340 var res
= verbatim_bound
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1345 redef fun can_resolve_for
(mtype
, anchor
, mmodule
)
1347 if mtype
.need_anchor
then
1348 assert anchor
!= null
1349 mtype
= mtype
.anchor_to
(mmodule
, anchor
)
1351 return mtype
.has_mproperty
(mmodule
, mproperty
)
1354 redef fun to_s
do return self.mproperty
.to_s
1356 redef fun full_name
do return self.mproperty
.full_name
1358 redef fun c_name
do return self.mproperty
.c_name
1361 # The type associated to a formal parameter generic type of a class
1363 # Each parameter type is associated to a specific class.
1364 # It means that all refinements of a same class "share" the parameter type,
1365 # but that a generic subclass has its own parameter types.
1367 # However, in the sense of the meta-model, a parameter type of a class is
1368 # a valid type in a subclass. The "in the sense of the meta-model" is
1369 # important because, in the Nit language, the programmer cannot refers
1370 # directly to the parameter types of the super-classes.
1375 # fun e: E is abstract
1381 # In the class definition B[F], `F` is a valid type but `E` is not.
1382 # However, `self.e` is a valid method call, and the signature of `e` is
1385 # Note that parameter types are shared among class refinements.
1386 # Therefore parameter only have an internal name (see `to_s` for details).
1387 class MParameterType
1390 # The generic class where the parameter belong
1393 redef fun model
do return self.mclass
.intro_mmodule
.model
1395 # The position of the parameter (0 for the first parameter)
1396 # FIXME: is `position` a better name?
1401 redef fun to_s
do return name
1403 redef var full_name
is lazy
do return "{mclass.full_name}::{name}"
1405 redef var c_name
is lazy
do return mclass
.c_name
+ "__" + "#{name}".to_cmangle
1407 redef fun lookup_bound
(mmodule
: MModule, resolved_receiver
: MType): MType
1409 assert not resolved_receiver
.need_anchor
1410 resolved_receiver
= resolved_receiver
.as_notnullable
1411 assert resolved_receiver
isa MClassType # It is the only remaining type
1412 var goalclass
= self.mclass
1413 if resolved_receiver
.mclass
== goalclass
then
1414 return resolved_receiver
.arguments
[self.rank
]
1416 var supertypes
= resolved_receiver
.collect_mtypes
(mmodule
)
1417 for t
in supertypes
do
1418 if t
.mclass
== goalclass
then
1419 # Yeah! c specialize goalclass with a "super `t'". So the question is what is the argument of f
1420 # FIXME: Here, we stop on the first goal. Should we check others and detect inconsistencies?
1421 var res
= t
.arguments
[self.rank
]
1428 # A PT is fixed when:
1429 # * Its bound is a enum class (see `enum_kind`).
1430 # The PT is just useless, but it is still a case.
1431 # * More usually, the `resolved_receiver` is a subclass of `self.mclass`,
1432 # so it is necessarily fixed in a `super` clause, either with a normal type
1433 # or with another PT.
1434 # See `resolve_for` for examples about related issues.
1435 redef fun lookup_fixed
(mmodule
: MModule, resolved_receiver
: MType): MType
1437 assert not resolved_receiver
.need_anchor
1438 resolved_receiver
= resolved_receiver
.as_notnullable
1439 assert resolved_receiver
isa MClassType # It is the only remaining type
1440 var res
= self.resolve_for
(resolved_receiver
.mclass
.mclass_type
, resolved_receiver
, mmodule
, false)
1444 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1446 assert can_resolve_for
(mtype
, anchor
, mmodule
)
1447 #print "{class_name}: {self}/{mtype}/{anchor}?"
1449 if mtype
isa MGenericType and mtype
.mclass
== self.mclass
then
1450 var res
= mtype
.arguments
[self.rank
]
1451 if anchor
!= null and res
.need_anchor
then
1452 # Maybe the result can be resolved more if are bound to a final class
1453 var r2
= res
.anchor_to
(mmodule
, anchor
)
1454 if r2
isa MClassType and r2
.mclass
.kind
== enum_kind
then return r2
1459 # self is a parameter type of mtype (or of a super-class of mtype)
1460 # The point of the function it to get the bound of the virtual type that make sense for mtype
1461 # But because mtype is maybe a virtual/formal type, we need to get a real receiver first
1462 # FIXME: What happens here is far from clear. Thus this part must be validated and clarified
1463 var resolved_receiver
1464 if mtype
.need_anchor
then
1465 assert anchor
!= null
1466 resolved_receiver
= mtype
.resolve_for
(anchor
.mclass
.mclass_type
, anchor
, mmodule
, true)
1468 resolved_receiver
= mtype
1470 if resolved_receiver
isa MNullableType then resolved_receiver
= resolved_receiver
.mtype
1471 if resolved_receiver
isa MParameterType then
1472 assert resolved_receiver
.mclass
== anchor
.mclass
1473 resolved_receiver
= anchor
.arguments
[resolved_receiver
.rank
]
1474 if resolved_receiver
isa MNullableType then resolved_receiver
= resolved_receiver
.mtype
1476 assert resolved_receiver
isa MClassType # It is the only remaining type
1478 # Eh! The parameter is in the current class.
1479 # So we return the corresponding argument, no mater what!
1480 if resolved_receiver
.mclass
== self.mclass
then
1481 var res
= resolved_receiver
.arguments
[self.rank
]
1482 #print "{class_name}: {self}/{mtype}/{anchor} -> direct {res}"
1486 if resolved_receiver
.need_anchor
then
1487 assert anchor
!= null
1488 resolved_receiver
= resolved_receiver
.resolve_for
(anchor
, null, mmodule
, false)
1490 # Now, we can get the bound
1491 var verbatim_bound
= lookup_bound
(mmodule
, resolved_receiver
)
1492 # The bound is exactly as declared in the "type" property, so we must resolve it again
1493 var res
= verbatim_bound
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1495 #print "{class_name}: {self}/{mtype}/{anchor} -> indirect {res}"
1500 redef fun can_resolve_for
(mtype
, anchor
, mmodule
)
1502 if mtype
.need_anchor
then
1503 assert anchor
!= null
1504 mtype
= mtype
.anchor_to
(mmodule
, anchor
)
1506 return mtype
.collect_mclassdefs
(mmodule
).has
(mclass
.intro
)
1510 # A type prefixed with "nullable"
1514 # The base type of the nullable type
1517 redef fun model
do return self.mtype
.model
1521 self.to_s
= "nullable {mtype}"
1524 redef var to_s
: String is noinit
1526 redef var full_name
is lazy
do return "nullable {mtype.full_name}"
1528 redef var c_name
is lazy
do return "nullable__{mtype.c_name}"
1530 redef fun need_anchor
do return mtype
.need_anchor
1531 redef fun as_nullable
do return self
1532 redef fun as_notnullable
do return mtype
1533 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1535 var res
= self.mtype
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1536 return res
.as_nullable
1539 redef fun can_resolve_for
(mtype
, anchor
, mmodule
)
1541 return self.mtype
.can_resolve_for
(mtype
, anchor
, mmodule
)
1544 # Efficiently returns `mtype.lookup_fixed(mmodule, resolved_receiver).as_nullable`
1545 redef fun lookup_fixed
(mmodule
, resolved_receiver
)
1547 var t
= mtype
.lookup_fixed
(mmodule
, resolved_receiver
)
1548 if t
== mtype
then return self
1549 return t
.as_nullable
1552 redef fun depth
do return self.mtype
.depth
1554 redef fun length
do return self.mtype
.length
1556 redef fun collect_mclassdefs
(mmodule
)
1558 assert not self.need_anchor
1559 return self.mtype
.collect_mclassdefs
(mmodule
)
1562 redef fun collect_mclasses
(mmodule
)
1564 assert not self.need_anchor
1565 return self.mtype
.collect_mclasses
(mmodule
)
1568 redef fun collect_mtypes
(mmodule
)
1570 assert not self.need_anchor
1571 return self.mtype
.collect_mtypes
(mmodule
)
1575 # The type of the only value null
1577 # The is only one null type per model, see `MModel::null_type`.
1580 redef var model
: Model
1581 redef fun to_s
do return "null"
1582 redef fun full_name
do return "null"
1583 redef fun c_name
do return "null"
1584 redef fun as_nullable
do return self
1585 redef fun need_anchor
do return false
1586 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
) do return self
1587 redef fun can_resolve_for
(mtype
, anchor
, mmodule
) do return true
1589 redef fun collect_mclassdefs
(mmodule
) do return new HashSet[MClassDef]
1591 redef fun collect_mclasses
(mmodule
) do return new HashSet[MClass]
1593 redef fun collect_mtypes
(mmodule
) do return new HashSet[MClassType]
1596 # A signature of a method
1600 # The each parameter (in order)
1601 var mparameters
: Array[MParameter]
1603 # The return type (null for a procedure)
1604 var return_mtype
: nullable MType
1609 var t
= self.return_mtype
1610 if t
!= null then dmax
= t
.depth
1611 for p
in mparameters
do
1612 var d
= p
.mtype
.depth
1613 if d
> dmax
then dmax
= d
1621 var t
= self.return_mtype
1622 if t
!= null then res
+= t
.length
1623 for p
in mparameters
do
1624 res
+= p
.mtype
.length
1629 # REQUIRE: 1 <= mparameters.count p -> p.is_vararg
1632 var vararg_rank
= -1
1633 for i
in [0..mparameters
.length
[ do
1634 var parameter
= mparameters
[i
]
1635 if parameter
.is_vararg
then
1636 assert vararg_rank
== -1
1640 self.vararg_rank
= vararg_rank
1643 # The rank of the ellipsis (`...`) for vararg (starting from 0).
1644 # value is -1 if there is no vararg.
1645 # Example: for "(a: Int, b: Bool..., c: Char)" #-> vararg_rank=1
1646 var vararg_rank
: Int is noinit
1648 # The number or parameters
1649 fun arity
: Int do return mparameters
.length
1653 var b
= new FlatBuffer
1654 if not mparameters
.is_empty
then
1656 for i
in [0..mparameters
.length
[ do
1657 var mparameter
= mparameters
[i
]
1658 if i
> 0 then b
.append
(", ")
1659 b
.append
(mparameter
.name
)
1661 b
.append
(mparameter
.mtype
.to_s
)
1662 if mparameter
.is_vararg
then
1668 var ret
= self.return_mtype
1676 redef fun resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule, cleanup_virtual
: Bool): MSignature
1678 var params
= new Array[MParameter]
1679 for p
in self.mparameters
do
1680 params
.add
(p
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
))
1682 var ret
= self.return_mtype
1684 ret
= ret
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1686 var res
= new MSignature(params
, ret
)
1691 # A parameter in a signature
1695 # The name of the parameter
1696 redef var name
: String
1698 # The static type of the parameter
1701 # Is the parameter a vararg?
1707 return "{name}: {mtype}..."
1709 return "{name}: {mtype}"
1713 # Returns a new parameter with the `mtype` resolved.
1714 # See `MType::resolve_for` for details.
1715 fun resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule, cleanup_virtual
: Bool): MParameter
1717 if not self.mtype
.need_anchor
then return self
1718 var newtype
= self.mtype
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1719 var res
= new MParameter(self.name
, newtype
, self.is_vararg
)
1723 redef fun model
do return mtype
.model
1726 # A service (global property) that generalize method, attribute, etc.
1728 # `MProperty` are global to the model; it means that a `MProperty` is not bound
1729 # to a specific `MModule` nor a specific `MClass`.
1731 # A MProperty gather definitions (see `mpropdefs`) ; one for the introduction
1732 # and the other in subclasses and in refinements.
1734 # A `MProperty` is used to denotes services in polymorphic way (ie. independent
1735 # of any dynamic type).
1736 # For instance, a call site "x.foo" is associated to a `MProperty`.
1737 abstract class MProperty
1740 # The associated MPropDef subclass.
1741 # The two specialization hierarchy are symmetric.
1742 type MPROPDEF: MPropDef
1744 # The classdef that introduce the property
1745 # While a property is not bound to a specific module, or class,
1746 # the introducing mclassdef is used for naming and visibility
1747 var intro_mclassdef
: MClassDef
1749 # The (short) name of the property
1750 redef var name
: String
1752 # The canonical name of the property.
1754 # It is the short-`name` prefixed by the short-name of the class and the full-name of the module.
1755 # Example: "my_project::my_module::MyClass::my_method"
1756 redef var full_name
is lazy
do
1757 return "{intro_mclassdef.mmodule.namespace_for(visibility)}::{intro_mclassdef.mclass.name}::{name}"
1760 redef var c_name
is lazy
do
1761 # FIXME use `namespace_for`
1762 return "{intro_mclassdef.mmodule.c_name}__{intro_mclassdef.mclass.name.to_cmangle}__{name.to_cmangle}"
1765 # The visibility of the property
1766 var visibility
: MVisibility
1770 intro_mclassdef
.intro_mproperties
.add
(self)
1771 var model
= intro_mclassdef
.mmodule
.model
1772 model
.mproperties_by_name
.add_one
(name
, self)
1773 model
.mproperties
.add
(self)
1776 # All definitions of the property.
1777 # The first is the introduction,
1778 # The other are redefinitions (in refinements and in subclasses)
1779 var mpropdefs
= new Array[MPROPDEF]
1781 # The definition that introduces the property.
1783 # Warning: such a definition may not exist in the early life of the object.
1784 # In this case, the method will abort.
1785 var intro
: MPROPDEF is noinit
1787 redef fun model
do return intro
.model
1790 redef fun to_s
do return name
1792 # Return the most specific property definitions defined or inherited by a type.
1793 # The selection knows that refinement is stronger than specialization;
1794 # however, in case of conflict more than one property are returned.
1795 # If mtype does not know mproperty then an empty array is returned.
1797 # If you want the really most specific property, then look at `lookup_first_definition`
1798 fun lookup_definitions
(mmodule
: MModule, mtype
: MType): Array[MPROPDEF]
1800 assert not mtype
.need_anchor
1801 mtype
= mtype
.as_notnullable
1803 var cache
= self.lookup_definitions_cache
[mmodule
, mtype
]
1804 if cache
!= null then return cache
1806 #print "select prop {mproperty} for {mtype} in {self}"
1807 # First, select all candidates
1808 var candidates
= new Array[MPROPDEF]
1809 for mpropdef
in self.mpropdefs
do
1810 # If the definition is not imported by the module, then skip
1811 if not mmodule
.in_importation
<= mpropdef
.mclassdef
.mmodule
then continue
1812 # If the definition is not inherited by the type, then skip
1813 if not mtype
.is_subtype
(mmodule
, null, mpropdef
.mclassdef
.bound_mtype
) then continue
1815 candidates
.add
(mpropdef
)
1817 # Fast track for only one candidate
1818 if candidates
.length
<= 1 then
1819 self.lookup_definitions_cache
[mmodule
, mtype
] = candidates
1823 # Second, filter the most specific ones
1824 return select_most_specific
(mmodule
, candidates
)
1827 private var lookup_definitions_cache
= new HashMap2[MModule, MType, Array[MPROPDEF]]
1829 # Return the most specific property definitions inherited by a type.
1830 # The selection knows that refinement is stronger than specialization;
1831 # however, in case of conflict more than one property are returned.
1832 # If mtype does not know mproperty then an empty array is returned.
1834 # If you want the really most specific property, then look at `lookup_next_definition`
1836 # FIXME: Move to `MPropDef`?
1837 fun lookup_super_definitions
(mmodule
: MModule, mtype
: MType): Array[MPROPDEF]
1839 assert not mtype
.need_anchor
1840 mtype
= mtype
.as_notnullable
1842 # First, select all candidates
1843 var candidates
= new Array[MPROPDEF]
1844 for mpropdef
in self.mpropdefs
do
1845 # If the definition is not imported by the module, then skip
1846 if not mmodule
.in_importation
<= mpropdef
.mclassdef
.mmodule
then continue
1847 # If the definition is not inherited by the type, then skip
1848 if not mtype
.is_subtype
(mmodule
, null, mpropdef
.mclassdef
.bound_mtype
) then continue
1849 # If the definition is defined by the type, then skip (we want the super, so e skip the current)
1850 if mtype
== mpropdef
.mclassdef
.bound_mtype
and mmodule
== mpropdef
.mclassdef
.mmodule
then continue
1852 candidates
.add
(mpropdef
)
1854 # Fast track for only one candidate
1855 if candidates
.length
<= 1 then return candidates
1857 # Second, filter the most specific ones
1858 return select_most_specific
(mmodule
, candidates
)
1861 # Return an array containing olny the most specific property definitions
1862 # This is an helper function for `lookup_definitions` and `lookup_super_definitions`
1863 private fun select_most_specific
(mmodule
: MModule, candidates
: Array[MPROPDEF]): Array[MPROPDEF]
1865 var res
= new Array[MPROPDEF]
1866 for pd1
in candidates
do
1867 var cd1
= pd1
.mclassdef
1870 for pd2
in candidates
do
1871 if pd2
== pd1
then continue # do not compare with self!
1872 var cd2
= pd2
.mclassdef
1874 if c2
.mclass_type
== c1
.mclass_type
then
1875 if cd2
.mmodule
.in_importation
< cd1
.mmodule
then
1876 # cd2 refines cd1; therefore we skip pd1
1880 else if cd2
.bound_mtype
.is_subtype
(mmodule
, null, cd1
.bound_mtype
) and cd2
.bound_mtype
!= cd1
.bound_mtype
then
1881 # cd2 < cd1; therefore we skip pd1
1890 if res
.is_empty
then
1891 print
"All lost! {candidates.join(", ")}"
1892 # FIXME: should be abort!
1897 # Return the most specific definition in the linearization of `mtype`.
1899 # If you want to know the next properties in the linearization,
1900 # look at `MPropDef::lookup_next_definition`.
1902 # FIXME: the linearization is still unspecified
1904 # REQUIRE: `not mtype.need_anchor`
1905 # REQUIRE: `mtype.has_mproperty(mmodule, self)`
1906 fun lookup_first_definition
(mmodule
: MModule, mtype
: MType): MPROPDEF
1908 assert mtype
.has_mproperty
(mmodule
, self)
1909 return lookup_all_definitions
(mmodule
, mtype
).first
1912 # Return all definitions in a linearization order
1913 # Most specific first, most general last
1914 fun lookup_all_definitions
(mmodule
: MModule, mtype
: MType): Array[MPROPDEF]
1916 assert not mtype
.need_anchor
1917 mtype
= mtype
.as_notnullable
1919 var cache
= self.lookup_all_definitions_cache
[mmodule
, mtype
]
1920 if cache
!= null then return cache
1922 #print "select prop {mproperty} for {mtype} in {self}"
1923 # First, select all candidates
1924 var candidates
= new Array[MPROPDEF]
1925 for mpropdef
in self.mpropdefs
do
1926 # If the definition is not imported by the module, then skip
1927 if not mmodule
.in_importation
<= mpropdef
.mclassdef
.mmodule
then continue
1928 # If the definition is not inherited by the type, then skip
1929 if not mtype
.is_subtype
(mmodule
, null, mpropdef
.mclassdef
.bound_mtype
) then continue
1931 candidates
.add
(mpropdef
)
1933 # Fast track for only one candidate
1934 if candidates
.length
<= 1 then
1935 self.lookup_all_definitions_cache
[mmodule
, mtype
] = candidates
1939 mmodule
.linearize_mpropdefs
(candidates
)
1940 candidates
= candidates
.reversed
1941 self.lookup_all_definitions_cache
[mmodule
, mtype
] = candidates
1945 private var lookup_all_definitions_cache
= new HashMap2[MModule, MType, Array[MPROPDEF]]
1952 redef type MPROPDEF: MMethodDef
1954 # Is the property defined at the top_level of the module?
1955 # Currently such a property are stored in `Object`
1956 var is_toplevel
: Bool = false is writable
1958 # Is the property a constructor?
1959 # Warning, this property can be inherited by subclasses with or without being a constructor
1960 # therefore, you should use `is_init_for` the verify if the property is a legal constructor for a given class
1961 var is_init
: Bool = false is writable
1963 # The constructor is a (the) root init with empty signature but a set of initializers
1964 var is_root_init
: Bool = false is writable
1966 # Is the property a 'new' constructor?
1967 var is_new
: Bool = false is writable
1969 # Is the property a legal constructor for a given class?
1970 # As usual, visibility is not considered.
1971 # FIXME not implemented
1972 fun is_init_for
(mclass
: MClass): Bool
1978 # A global attribute
1982 redef type MPROPDEF: MAttributeDef
1986 # A global virtual type
1987 class MVirtualTypeProp
1990 redef type MPROPDEF: MVirtualTypeDef
1992 # The formal type associated to the virtual type property
1993 var mvirtualtype
= new MVirtualType(self)
1996 # A definition of a property (local property)
1998 # Unlike `MProperty`, a `MPropDef` is a local definition that belong to a
1999 # specific class definition (which belong to a specific module)
2000 abstract class MPropDef
2003 # The associated `MProperty` subclass.
2004 # the two specialization hierarchy are symmetric
2005 type MPROPERTY: MProperty
2008 type MPROPDEF: MPropDef
2010 # The class definition where the property definition is
2011 var mclassdef
: MClassDef
2013 # The associated global property
2014 var mproperty
: MPROPERTY
2016 # The origin of the definition
2017 var location
: Location
2021 mclassdef
.mpropdefs
.add
(self)
2022 mproperty
.mpropdefs
.add
(self)
2023 if mproperty
.intro_mclassdef
== mclassdef
then
2024 assert not isset mproperty
._intro
2025 mproperty
.intro
= self
2027 self.to_s
= "{mclassdef}#{mproperty}"
2030 # Actually the name of the `mproperty`
2031 redef fun name
do return mproperty
.name
2033 # The full-name of mpropdefs combine the information about the `classdef` and the `mproperty`.
2035 # Therefore the combination of identifiers is awful,
2036 # the worst case being
2038 # * a property "p::m::A::x"
2039 # * redefined in a refinement of a class "q::n::B"
2040 # * in a module "r::o"
2041 # * so "r::o#q::n::B#p::m::A::x"
2043 # Fortunately, the full-name is simplified when entities are repeated.
2044 # For the previous case, the simplest form is "p#A#x".
2045 redef var full_name
is lazy
do
2046 var res
= new FlatBuffer
2048 # The first part is the mclassdef. Worst case is "r::o#q::n::B"
2049 res
.append mclassdef
.full_name
2053 if mclassdef
.mclass
== mproperty
.intro_mclassdef
.mclass
then
2054 # intro are unambiguous in a class
2057 # Just try to simplify each part
2058 if mclassdef
.mmodule
.mproject
!= mproperty
.intro_mclassdef
.mmodule
.mproject
then
2059 # precise "p::m" only if "p" != "r"
2060 res
.append mproperty
.intro_mclassdef
.mmodule
.full_name
2062 else if mproperty
.visibility
<= private_visibility
then
2063 # Same project ("p"=="q"), but private visibility,
2064 # does the module part ("::m") need to be displayed
2065 if mclassdef
.mmodule
.namespace_for
(mclassdef
.mclass
.visibility
) != mproperty
.intro_mclassdef
.mmodule
.mproject
then
2067 res
.append mproperty
.intro_mclassdef
.mmodule
.name
2071 if mclassdef
.mclass
!= mproperty
.intro_mclassdef
.mclass
then
2072 # precise "B" only if not the same class than "A"
2073 res
.append mproperty
.intro_mclassdef
.name
2076 # Always use the property name "x"
2077 res
.append mproperty
.name
2082 redef var c_name
is lazy
do
2083 var res
= new FlatBuffer
2084 res
.append mclassdef
.c_name
2086 if mclassdef
.mclass
== mproperty
.intro_mclassdef
.mclass
then
2087 res
.append name
.to_cmangle
2089 if mclassdef
.mmodule
!= mproperty
.intro_mclassdef
.mmodule
then
2090 res
.append mproperty
.intro_mclassdef
.mmodule
.c_name
2093 if mclassdef
.mclass
!= mproperty
.intro_mclassdef
.mclass
then
2094 res
.append mproperty
.intro_mclassdef
.name
.to_cmangle
2097 res
.append mproperty
.name
.to_cmangle
2102 redef fun model
do return mclassdef
.model
2104 # Internal name combining the module, the class and the property
2105 # Example: "mymodule#MyClass#mymethod"
2106 redef var to_s
: String is noinit
2108 # Is self the definition that introduce the property?
2109 fun is_intro
: Bool do return mproperty
.intro
== self
2111 # Return the next definition in linearization of `mtype`.
2113 # This method is used to determine what method is called by a super.
2115 # REQUIRE: `not mtype.need_anchor`
2116 fun lookup_next_definition
(mmodule
: MModule, mtype
: MType): MPROPDEF
2118 assert not mtype
.need_anchor
2120 var mpropdefs
= self.mproperty
.lookup_all_definitions
(mmodule
, mtype
)
2121 var i
= mpropdefs
.iterator
2122 while i
.is_ok
and i
.item
!= self do i
.next
2123 assert has_property
: i
.is_ok
2125 assert has_next_property
: i
.is_ok
2130 # A local definition of a method
2134 redef type MPROPERTY: MMethod
2135 redef type MPROPDEF: MMethodDef
2137 # The signature attached to the property definition
2138 var msignature
: nullable MSignature = null is writable
2140 # The signature attached to the `new` call on a root-init
2141 # This is a concatenation of the signatures of the initializers
2143 # REQUIRE `mproperty.is_root_init == (new_msignature != null)`
2144 var new_msignature
: nullable MSignature = null is writable
2146 # List of initialisers to call in root-inits
2148 # They could be setters or attributes
2150 # REQUIRE `mproperty.is_root_init == (new_msignature != null)`
2151 var initializers
= new Array[MProperty]
2153 # Is the method definition abstract?
2154 var is_abstract
: Bool = false is writable
2156 # Is the method definition intern?
2157 var is_intern
= false is writable
2159 # Is the method definition extern?
2160 var is_extern
= false is writable
2162 # An optional constant value returned in functions.
2164 # Only some specific primitife value are accepted by engines.
2165 # Is used when there is no better implementation available.
2167 # Currently used only for the implementation of the `--define`
2168 # command-line option.
2169 # SEE: module `mixin`.
2170 var constant_value
: nullable Object = null is writable
2173 # A local definition of an attribute
2177 redef type MPROPERTY: MAttribute
2178 redef type MPROPDEF: MAttributeDef
2180 # The static type of the attribute
2181 var static_mtype
: nullable MType = null is writable
2184 # A local definition of a virtual type
2185 class MVirtualTypeDef
2188 redef type MPROPERTY: MVirtualTypeProp
2189 redef type MPROPDEF: MVirtualTypeDef
2191 # The bound of the virtual type
2192 var bound
: nullable MType = null is writable
2194 # Is the bound fixed?
2195 var is_fixed
= false is writable
2202 # * `interface_kind`
2206 # Note this class is basically an enum.
2207 # FIXME: use a real enum once user-defined enums are available
2209 redef var to_s
: String
2211 # Is a constructor required?
2214 # TODO: private init because enumeration.
2216 # Can a class of kind `self` specializes a class of kine `other`?
2217 fun can_specialize
(other
: MClassKind): Bool
2219 if other
== interface_kind
then return true # everybody can specialize interfaces
2220 if self == interface_kind
or self == enum_kind
then
2221 # no other case for interfaces
2223 else if self == extern_kind
then
2224 # only compatible with themselves
2225 return self == other
2226 else if other
== enum_kind
or other
== extern_kind
then
2227 # abstract_kind and concrete_kind are incompatible
2230 # remain only abstract_kind and concrete_kind
2235 # The class kind `abstract`
2236 fun abstract_kind
: MClassKind do return once
new MClassKind("abstract class", true)
2237 # The class kind `concrete`
2238 fun concrete_kind
: MClassKind do return once
new MClassKind("class", true)
2239 # The class kind `interface`
2240 fun interface_kind
: MClassKind do return once
new MClassKind("interface", false)
2241 # The class kind `enum`
2242 fun enum_kind
: MClassKind do return once
new MClassKind("enum", false)
2243 # The class kind `extern`
2244 fun extern_kind
: MClassKind do return once
new MClassKind("extern class", false)