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 `Char`
210 var char_type
: MClassType = self.get_primitive_class
("Char").mclass_type
is lazy
212 # The primitive type `Float`
213 var float_type
: MClassType = self.get_primitive_class
("Float").mclass_type
is lazy
215 # The primitive type `String`
216 var string_type
: MClassType = self.get_primitive_class
("String").mclass_type
is lazy
218 # The primitive type `NativeString`
219 var native_string_type
: MClassType = self.get_primitive_class
("NativeString").mclass_type
is lazy
221 # A primitive type of `Array`
222 fun array_type
(elt_type
: MType): MClassType do return array_class
.get_mtype
([elt_type
])
224 # The primitive class `Array`
225 var array_class
: MClass = self.get_primitive_class
("Array") is lazy
227 # A primitive type of `NativeArray`
228 fun native_array_type
(elt_type
: MType): MClassType do return native_array_class
.get_mtype
([elt_type
])
230 # The primitive class `NativeArray`
231 var native_array_class
: MClass = self.get_primitive_class
("NativeArray") is lazy
233 # The primitive type `Sys`, the main type of the program, if any
234 fun sys_type
: nullable MClassType
236 var clas
= self.model
.get_mclasses_by_name
("Sys")
237 if clas
== null then return null
238 return get_primitive_class
("Sys").mclass_type
241 # The primitive type `Finalizable`
242 # Used to tag classes that need to be finalized.
243 fun finalizable_type
: nullable MClassType
245 var clas
= self.model
.get_mclasses_by_name
("Finalizable")
246 if clas
== null then return null
247 return get_primitive_class
("Finalizable").mclass_type
250 # Force to get the primitive class named `name` or abort
251 fun get_primitive_class
(name
: String): MClass
253 var cla
= self.model
.get_mclasses_by_name
(name
)
254 # Filter classes by introducing module
255 if cla
!= null then cla
= [for c
in cla
do if self.in_importation
<= c
.intro_mmodule
then c
]
256 if cla
== null or cla
.is_empty
then
257 if name
== "Bool" and self.model
.get_mclasses_by_name
("Object") != null then
258 # Bool is injected because it is needed by engine to code the result
259 # of the implicit casts.
260 var c
= new MClass(self, name
, null, enum_kind
, public_visibility
)
261 var cladef
= new MClassDef(self, c
.mclass_type
, new Location(null, 0,0,0,0))
262 cladef
.set_supertypes
([object_type
])
263 cladef
.add_in_hierarchy
266 print
("Fatal Error: no primitive class {name} in {self}")
269 if cla
.length
!= 1 then
270 var msg
= "Fatal Error: more than one primitive class {name} in {self}:"
271 for c
in cla
do msg
+= " {c.full_name}"
278 # Try to get the primitive method named `name` on the type `recv`
279 fun try_get_primitive_method
(name
: String, recv
: MClass): nullable MMethod
281 var props
= self.model
.get_mproperties_by_name
(name
)
282 if props
== null then return null
283 var res
: nullable MMethod = null
284 for mprop
in props
do
285 assert mprop
isa MMethod
286 var intro
= mprop
.intro_mclassdef
287 for mclassdef
in recv
.mclassdefs
do
288 if not self.in_importation
.greaters
.has
(mclassdef
.mmodule
) then continue
289 if not mclassdef
.in_hierarchy
.greaters
.has
(intro
) then continue
292 else if res
!= mprop
then
293 print
("Fatal Error: ambigous property name '{name}'; conflict between {mprop.full_name} and {res.full_name}")
302 private class MClassDefSorter
304 redef type COMPARED: MClassDef
306 redef fun compare
(a
, b
)
310 if ca
!= cb
then return mmodule
.flatten_mclass_hierarchy
.compare
(ca
, cb
)
311 return mmodule
.model
.mclassdef_hierarchy
.compare
(a
, b
)
315 private class MPropDefSorter
317 redef type COMPARED: MPropDef
319 redef fun compare
(pa
, pb
)
325 if ca
!= cb
then return mmodule
.flatten_mclass_hierarchy
.compare
(ca
, cb
)
326 return mmodule
.model
.mclassdef_hierarchy
.compare
(a
, b
)
332 # `MClass` are global to the model; it means that a `MClass` is not bound to a
333 # specific `MModule`.
335 # This characteristic helps the reasoning about classes in a program since a
336 # single `MClass` object always denote the same class.
338 # The drawback is that classes (`MClass`) contain almost nothing by themselves.
339 # These do not really have properties nor belong to a hierarchy since the property and the
340 # hierarchy of a class depends of the refinement in the modules.
342 # Most services on classes require the precision of a module, and no one can asks what are
343 # the super-classes of a class nor what are properties of a class without precising what is
344 # the module considered.
346 # For instance, during the typing of a source-file, the module considered is the module of the file.
347 # eg. the question *is the method `foo` exists in the class `Bar`?* must be reformulated into
348 # *is the method `foo` exists in the class `Bar` in the current module?*
350 # During some global analysis, the module considered may be the main module of the program.
354 # The module that introduce the class
355 # While classes are not bound to a specific module,
356 # the introducing module is used for naming an visibility
357 var intro_mmodule
: MModule
359 # The short name of the class
360 # In Nit, the name of a class cannot evolve in refinements
361 redef var name
: String
363 # The canonical name of the class
365 # It is the name of the class prefixed by the full_name of the `intro_mmodule`
366 # Example: `"owner::module::MyClass"`
367 redef var full_name
is lazy
do
368 return "{self.intro_mmodule.namespace_for(visibility)}::{name}"
371 redef var c_name
is lazy
do
372 return "{intro_mmodule.c_namespace_for(visibility)}__{name.to_cmangle}"
375 # The number of generic formal parameters
376 # 0 if the class is not generic
377 var arity
: Int is noinit
379 # Each generic formal parameters in order.
380 # is empty if the class is not generic
381 var mparameters
= new Array[MParameterType]
383 # A string version of the signature a generic class.
385 # eg. `Map[K: nullable Object, V: nullable Object]`
387 # If the class in non generic the name is just given.
390 fun signature_to_s
: String
392 if arity
== 0 then return name
393 var res
= new FlatBuffer
396 for i
in [0..arity
[ do
397 if i
> 0 then res
.append
", "
398 res
.append mparameters
[i
].name
400 res
.append intro
.bound_mtype
.arguments
[i
].to_s
406 # Initialize `mparameters` from their names.
407 protected fun setup_parameter_names
(parameter_names
: nullable Array[String]) is
410 if parameter_names
== null then
413 self.arity
= parameter_names
.length
416 # Create the formal parameter types
418 assert parameter_names
!= null
419 var mparametertypes
= new Array[MParameterType]
420 for i
in [0..arity
[ do
421 var mparametertype
= new MParameterType(self, i
, parameter_names
[i
])
422 mparametertypes
.add
(mparametertype
)
424 self.mparameters
= mparametertypes
425 var mclass_type
= new MGenericType(self, mparametertypes
)
426 self.mclass_type
= mclass_type
427 self.get_mtype_cache
[mparametertypes
] = mclass_type
429 self.mclass_type
= new MClassType(self)
433 # The kind of the class (interface, abstract class, etc.)
434 # In Nit, the kind of a class cannot evolve in refinements
437 # The visibility of the class
438 # In Nit, the visibility of a class cannot evolve in refinements
439 var visibility
: MVisibility
443 intro_mmodule
.intro_mclasses
.add
(self)
444 var model
= intro_mmodule
.model
445 model
.mclasses_by_name
.add_one
(name
, self)
446 model
.mclasses
.add
(self)
449 redef fun model
do return intro_mmodule
.model
451 # All class definitions (introduction and refinements)
452 var mclassdefs
= new Array[MClassDef]
455 redef fun to_s
do return self.name
457 # The definition that introduces the class.
459 # Warning: such a definition may not exist in the early life of the object.
460 # In this case, the method will abort.
462 # Use `try_intro` instead
463 var intro
: MClassDef is noinit
465 # The definition that introduces the class or null if not yet known.
468 fun try_intro
: nullable MClassDef do
469 if isset _intro
then return _intro
else return null
472 # Return the class `self` in the class hierarchy of the module `mmodule`.
474 # SEE: `MModule::flatten_mclass_hierarchy`
475 # REQUIRE: `mmodule.has_mclass(self)`
476 fun in_hierarchy
(mmodule
: MModule): POSetElement[MClass]
478 return mmodule
.flatten_mclass_hierarchy
[self]
481 # The principal static type of the class.
483 # For non-generic class, mclass_type is the only `MClassType` based
486 # For a generic class, the arguments are the formal parameters.
487 # i.e.: for the class Array[E:Object], the `mclass_type` is Array[E].
488 # If you want Array[Object] the see `MClassDef::bound_mtype`
490 # For generic classes, the mclass_type is also the way to get a formal
491 # generic parameter type.
493 # To get other types based on a generic class, see `get_mtype`.
495 # ENSURE: `mclass_type.mclass == self`
496 var mclass_type
: MClassType is noinit
498 # Return a generic type based on the class
499 # Is the class is not generic, then the result is `mclass_type`
501 # REQUIRE: `mtype_arguments.length == self.arity`
502 fun get_mtype
(mtype_arguments
: Array[MType]): MClassType
504 assert mtype_arguments
.length
== self.arity
505 if self.arity
== 0 then return self.mclass_type
506 var res
= get_mtype_cache
.get_or_null
(mtype_arguments
)
507 if res
!= null then return res
508 res
= new MGenericType(self, mtype_arguments
)
509 self.get_mtype_cache
[mtype_arguments
.to_a
] = res
513 private var get_mtype_cache
= new HashMap[Array[MType], MGenericType]
515 # Is there a `new` factory to allow the pseudo instantiation?
516 var has_new_factory
= false is writable
520 # A definition (an introduction or a refinement) of a class in a module
522 # A `MClassDef` is associated with an explicit (or almost) definition of a
523 # class. Unlike `MClass`, a `MClassDef` is a local definition that belong to
524 # a specific class and a specific module, and contains declarations like super-classes
527 # It is the class definitions that are the backbone of most things in the model:
528 # ClassDefs are defined with regard with other classdefs.
529 # Refinement and specialization are combined to produce a big poset called the `Model::mclassdef_hierarchy`.
531 # Moreover, the extension and the intention of types is defined by looking at the MClassDefs.
535 # The module where the definition is
538 # The associated `MClass`
539 var mclass
: MClass is noinit
541 # The bounded type associated to the mclassdef
543 # For a non-generic class, `bound_mtype` and `mclass.mclass_type`
547 # For the classdef Array[E: Object], the bound_mtype is Array[Object].
548 # If you want Array[E], then see `mclass.mclass_type`
550 # ENSURE: `bound_mtype.mclass == self.mclass`
551 var bound_mtype
: MClassType
553 # The origin of the definition
554 var location
: Location
556 # Internal name combining the module and the class
557 # Example: "mymodule#MyClass"
558 redef var to_s
: String is noinit
562 self.mclass
= bound_mtype
.mclass
563 mmodule
.mclassdefs
.add
(self)
564 mclass
.mclassdefs
.add
(self)
565 if mclass
.intro_mmodule
== mmodule
then
566 assert not isset mclass
._intro
569 self.to_s
= "{mmodule}#{mclass}"
572 # Actually the name of the `mclass`
573 redef fun name
do return mclass
.name
575 # The module and class name separated by a '#'.
577 # The short-name of the class is used for introduction.
578 # Example: "my_module#MyClass"
580 # The full-name of the class is used for refinement.
581 # Example: "my_module#intro_module::MyClass"
582 redef var full_name
is lazy
do
585 # private gives 'p::m#A'
586 return "{mmodule.namespace_for(mclass.visibility)}#{mclass.name}"
587 else if mclass
.intro_mmodule
.mproject
!= mmodule
.mproject
then
588 # public gives 'q::n#p::A'
589 # private gives 'q::n#p::m::A'
590 return "{mmodule.full_name}#{mclass.full_name}"
591 else if mclass
.visibility
> private_visibility
then
592 # public gives 'p::n#A'
593 return "{mmodule.full_name}#{mclass.name}"
595 # private gives 'p::n#::m::A' (redundant p is omitted)
596 return "{mmodule.full_name}#::{mclass.intro_mmodule.name}::{mclass.name}"
600 redef var c_name
is lazy
do
602 return "{mmodule.c_namespace_for(mclass.visibility)}___{mclass.c_name}"
603 else if mclass
.intro_mmodule
.mproject
== mmodule
.mproject
and mclass
.visibility
> private_visibility
then
604 return "{mmodule.c_name}___{mclass.name.to_cmangle}"
606 return "{mmodule.c_name}___{mclass.c_name}"
610 redef fun model
do return mmodule
.model
612 # All declared super-types
613 # FIXME: quite ugly but not better idea yet
614 var supertypes
= new Array[MClassType]
616 # Register some super-types for the class (ie "super SomeType")
618 # The hierarchy must not already be set
619 # REQUIRE: `self.in_hierarchy == null`
620 fun set_supertypes
(supertypes
: Array[MClassType])
622 assert unique_invocation
: self.in_hierarchy
== null
623 var mmodule
= self.mmodule
624 var model
= mmodule
.model
625 var mtype
= self.bound_mtype
627 for supertype
in supertypes
do
628 self.supertypes
.add
(supertype
)
630 # Register in full_type_specialization_hierarchy
631 model
.full_mtype_specialization_hierarchy
.add_edge
(mtype
, supertype
)
632 # Register in intro_type_specialization_hierarchy
633 if mclass
.intro_mmodule
== mmodule
and supertype
.mclass
.intro_mmodule
== mmodule
then
634 model
.intro_mtype_specialization_hierarchy
.add_edge
(mtype
, supertype
)
640 # Collect the super-types (set by set_supertypes) to build the hierarchy
642 # This function can only invoked once by class
643 # REQUIRE: `self.in_hierarchy == null`
644 # ENSURE: `self.in_hierarchy != null`
647 assert unique_invocation
: self.in_hierarchy
== null
648 var model
= mmodule
.model
649 var res
= model
.mclassdef_hierarchy
.add_node
(self)
650 self.in_hierarchy
= res
651 var mtype
= self.bound_mtype
653 # Here we need to connect the mclassdef to its pairs in the mclassdef_hierarchy
654 # The simpliest way is to attach it to collect_mclassdefs
655 for mclassdef
in mtype
.collect_mclassdefs
(mmodule
) do
656 res
.poset
.add_edge
(self, mclassdef
)
660 # The view of the class definition in `mclassdef_hierarchy`
661 var in_hierarchy
: nullable POSetElement[MClassDef] = null
663 # Is the definition the one that introduced `mclass`?
664 fun is_intro
: Bool do return isset mclass
._intro
and mclass
.intro
== self
666 # All properties introduced by the classdef
667 var intro_mproperties
= new Array[MProperty]
669 # All property definitions in the class (introductions and redefinitions)
670 var mpropdefs
= new Array[MPropDef]
673 # A global static type
675 # MType are global to the model; it means that a `MType` is not bound to a
676 # specific `MModule`.
677 # This characteristic helps the reasoning about static types in a program
678 # since a single `MType` object always denote the same type.
680 # However, because a `MType` is global, it does not really have properties
681 # nor have subtypes to a hierarchy since the property and the class hierarchy
682 # depends of a module.
683 # Moreover, virtual types an formal generic parameter types also depends on
684 # a receiver to have sense.
686 # Therefore, most method of the types require a module and an anchor.
687 # The module is used to know what are the classes and the specialization
689 # The anchor is used to know what is the bound of the virtual types and formal
690 # generic parameter types.
692 # MType are not directly usable to get properties. See the `anchor_to` method
693 # and the `MClassType` class.
695 # FIXME: the order of the parameters is not the best. We mus pick on from:
696 # * foo(mmodule, anchor, othertype)
697 # * foo(othertype, anchor, mmodule)
698 # * foo(anchor, mmodule, othertype)
699 # * foo(othertype, mmodule, anchor)
703 redef fun name
do return to_s
705 # Return true if `self` is an subtype of `sup`.
706 # The typing is done using the standard typing policy of Nit.
708 # REQUIRE: `anchor == null implies not self.need_anchor and not sup.need_anchor`
709 # REQUIRE: `anchor != null implies self.can_resolve_for(anchor, null, mmodule) and sup.can_resolve_for(anchor, null, mmodule)`
710 fun is_subtype
(mmodule
: MModule, anchor
: nullable MClassType, sup
: MType): Bool
713 if sub
== sup
then return true
715 #print "1.is {sub} a {sup}? ===="
717 if anchor
== null then
718 assert not sub
.need_anchor
719 assert not sup
.need_anchor
721 # First, resolve the formal types to the simplest equivalent forms in the receiver
722 assert sub
.can_resolve_for
(anchor
, null, mmodule
)
723 sub
= sub
.lookup_fixed
(mmodule
, anchor
)
724 assert sup
.can_resolve_for
(anchor
, null, mmodule
)
725 sup
= sup
.lookup_fixed
(mmodule
, anchor
)
728 # Does `sup` accept null or not?
729 # Discard the nullable marker if it exists
730 var sup_accept_null
= false
731 if sup
isa MNullableType then
732 sup_accept_null
= true
734 else if sup
isa MNotNullType then
736 else if sup
isa MNullType then
737 sup_accept_null
= true
740 # Can `sub` provide null or not?
741 # Thus we can match with `sup_accept_null`
742 # Also discard the nullable marker if it exists
743 var sub_reject_null
= false
744 if sub
isa MNullableType then
745 if not sup_accept_null
then return false
747 else if sub
isa MNotNullType then
748 sub_reject_null
= true
750 else if sub
isa MNullType then
751 return sup_accept_null
753 # Now the case of direct null and nullable is over.
755 # If `sub` is a formal type, then it is accepted if its bound is accepted
756 while sub
isa MFormalType do
757 #print "3.is {sub} a {sup}?"
759 # A unfixed formal type can only accept itself
760 if sub
== sup
then return true
762 assert anchor
!= null
763 sub
= sub
.lookup_bound
(mmodule
, anchor
)
764 if sub_reject_null
then sub
= sub
.as_notnull
766 #print "3.is {sub} a {sup}?"
768 # Manage the second layer of null/nullable
769 if sub
isa MNullableType then
770 if not sup_accept_null
and not sub_reject_null
then return false
772 else if sub
isa MNotNullType then
773 sub_reject_null
= true
775 else if sub
isa MNullType then
776 return sup_accept_null
779 #print "4.is {sub} a {sup}? <- no more resolution"
781 assert sub
isa MClassType else print
"{sub} <? {sub}" # It is the only remaining type
783 # A unfixed formal type can only accept itself
784 if sup
isa MFormalType then
788 if sup
isa MNullType then
789 # `sup` accepts only null
793 assert sup
isa MClassType # It is the only remaining type
795 # Now both are MClassType, we need to dig
797 if sub
== sup
then return true
799 if anchor
== null then anchor
= sub
# UGLY: any anchor will work
800 var resolved_sub
= sub
.anchor_to
(mmodule
, anchor
)
801 var res
= resolved_sub
.collect_mclasses
(mmodule
).has
(sup
.mclass
)
802 if res
== false then return false
803 if not sup
isa MGenericType then return true
804 var sub2
= sub
.supertype_to
(mmodule
, anchor
, sup
.mclass
)
805 assert sub2
.mclass
== sup
.mclass
806 for i
in [0..sup
.mclass
.arity
[ do
807 var sub_arg
= sub2
.arguments
[i
]
808 var sup_arg
= sup
.arguments
[i
]
809 res
= sub_arg
.is_subtype
(mmodule
, anchor
, sup_arg
)
810 if res
== false then return false
815 # The base class type on which self is based
817 # This base type is used to get property (an internally to perform
818 # unsafe type comparison).
820 # Beware: some types (like null) are not based on a class thus this
823 # Basically, this function transform the virtual types and parameter
824 # types to their bounds.
829 # class B super A end
831 # class Y super X end
840 # Map[T,U] anchor_to H #-> Map[B,Y]
842 # Explanation of the example:
843 # In H, T is set to B, because "H super G[B]", and U is bound to Y,
844 # because "redef type U: Y". Therefore, Map[T, U] is bound to
847 # ENSURE: `not self.need_anchor implies result == self`
848 # ENSURE: `not result.need_anchor`
849 fun anchor_to
(mmodule
: MModule, anchor
: MClassType): MType
851 if not need_anchor
then return self
852 assert not anchor
.need_anchor
853 # Just resolve to the anchor and clear all the virtual types
854 var res
= self.resolve_for
(anchor
, null, mmodule
, true)
855 assert not res
.need_anchor
859 # Does `self` contain a virtual type or a formal generic parameter type?
860 # In order to remove those types, you usually want to use `anchor_to`.
861 fun need_anchor
: Bool do return true
863 # Return the supertype when adapted to a class.
865 # In Nit, for each super-class of a type, there is a equivalent super-type.
871 # class H[V] super G[V, Bool] end
873 # H[Int] supertype_to G #-> G[Int, Bool]
876 # REQUIRE: `super_mclass` is a super-class of `self`
877 # REQUIRE: `self.need_anchor implies anchor != null and self.can_resolve_for(anchor, null, mmodule)`
878 # ENSURE: `result.mclass = super_mclass`
879 fun supertype_to
(mmodule
: MModule, anchor
: nullable MClassType, super_mclass
: MClass): MClassType
881 if super_mclass
.arity
== 0 then return super_mclass
.mclass_type
882 if self isa MClassType and self.mclass
== super_mclass
then return self
884 if self.need_anchor
then
885 assert anchor
!= null
886 resolved_self
= self.anchor_to
(mmodule
, anchor
)
890 var supertypes
= resolved_self
.collect_mtypes
(mmodule
)
891 for supertype
in supertypes
do
892 if supertype
.mclass
== super_mclass
then
893 # FIXME: Here, we stop on the first goal. Should we check others and detect inconsistencies?
894 return supertype
.resolve_for
(self, anchor
, mmodule
, false)
900 # Replace formals generic types in self with resolved values in `mtype`
901 # If `cleanup_virtual` is true, then virtual types are also replaced
904 # This function returns self if `need_anchor` is false.
910 # class H[F] super G[F] end
914 # * Array[E].resolve_for(H[Int]) #-> Array[Int]
915 # * Array[E].resolve_for(G[Z], X[Int]) #-> Array[Z]
917 # Explanation of the example:
918 # * Array[E].need_anchor is true because there is a formal generic parameter type E
919 # * E makes sense for H[Int] because E is a formal parameter of G and H specialize G
920 # * Since "H[F] super G[F]", E is in fact F for H
921 # * More specifically, in H[Int], E is Int
922 # * So, in H[Int], Array[E] is Array[Int]
924 # This function is mainly used to inherit a signature.
925 # Because, unlike `anchor_to`, we do not want a full resolution of
926 # a type but only an adapted version of it.
932 # fun foo(e:E):E is abstract
934 # class B super A[Int] end
937 # The signature on foo is (e: E): E
938 # If we resolve the signature for B, we get (e:Int):Int
944 # fun foo(e:E):E is abstract
948 # fun bar do a.foo(x) # <- x is here
952 # The first question is: is foo available on `a`?
954 # The static type of a is `A[Array[F]]`, that is an open type.
955 # in order to find a method `foo`, whe must look at a resolved type.
957 # A[Array[F]].anchor_to(C[nullable Object]) #-> A[Array[nullable Object]]
959 # the method `foo` exists in `A[Array[nullable Object]]`, therefore `foo` exists for `a`.
961 # The next question is: what is the accepted types for `x`?
963 # the signature of `foo` is `foo(e:E)`, thus we must resolve the type E
965 # E.resolve_for(A[Array[F]],C[nullable Object]) #-> Array[F]
967 # The resolution can be done because `E` make sense for the class A (see `can_resolve_for`)
969 # FIXME: the parameter `cleanup_virtual` is just a bad idea, but having
970 # two function instead of one seems also to be a bad idea.
972 # REQUIRE: `can_resolve_for(mtype, anchor, mmodule)`
973 # ENSURE: `not self.need_anchor implies result == self`
974 fun resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule, cleanup_virtual
: Bool): MType is abstract
976 # Resolve formal type to its verbatim bound.
977 # If the type is not formal, just return self
979 # The result is returned exactly as declared in the "type" property (verbatim).
980 # So it could be another formal type.
982 # In case of conflict, the method aborts.
983 fun lookup_bound
(mmodule
: MModule, resolved_receiver
: MType): MType do return self
985 # Resolve the formal type to its simplest equivalent form.
987 # Formal types are either free or fixed.
988 # When it is fixed, it means that it is equivalent with a simpler type.
989 # When a formal type is free, it means that it is only equivalent with itself.
990 # This method return the most simple equivalent type of `self`.
992 # This method is mainly used for subtype test in order to sanely compare fixed.
994 # By default, return self.
995 # See the redefinitions for specific behavior in each kind of type.
996 fun lookup_fixed
(mmodule
: MModule, resolved_receiver
: MType): MType do return self
998 # Can the type be resolved?
1000 # In order to resolve open types, the formal types must make sence.
1010 # E.can_resolve_for(A[Int]) #-> true, E make sense in A
1012 # E.can_resolve_for(B[Int]) #-> false, E does not make sense in B
1014 # B[E].can_resolve_for(A[F], B[Object]) #-> true,
1015 # # B[E] is a red hearing only the E is important,
1016 # # E make sense in A
1019 # REQUIRE: `anchor != null implies not anchor.need_anchor`
1020 # REQUIRE: `mtype.need_anchor implies anchor != null and mtype.can_resolve_for(anchor, null, mmodule)`
1021 # ENSURE: `not self.need_anchor implies result == true`
1022 fun can_resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule): Bool is abstract
1024 # Return the nullable version of the type
1025 # If the type is already nullable then self is returned
1026 fun as_nullable
: MType
1028 var res
= self.as_nullable_cache
1029 if res
!= null then return res
1030 res
= new MNullableType(self)
1031 self.as_nullable_cache
= res
1035 # Remove the base type of a decorated (proxy) type.
1036 # Is the type is not decorated, then self is returned.
1038 # Most of the time it is used to return the not nullable version of a nullable type.
1039 # In this case, this just remove the `nullable` notation, but the result can still contains null.
1040 # For instance if `self isa MNullType` or self is a formal type bounded by a nullable type.
1041 # If you really want to exclude the `null` value, then use `as_notnull`
1042 fun undecorate
: MType
1047 # Returns the not null version of the type.
1048 # That is `self` minus the `null` value.
1050 # For most types, this return `self`.
1051 # For formal types, this returns a special `MNotNullType`
1052 fun as_notnull
: MType do return self
1054 private var as_nullable_cache
: nullable MType = null
1057 # The depth of the type seen as a tree.
1064 # Formal types have a depth of 1.
1070 # The length of the type seen as a tree.
1077 # Formal types have a length of 1.
1083 # Compute all the classdefs inherited/imported.
1084 # The returned set contains:
1085 # * the class definitions from `mmodule` and its imported modules
1086 # * the class definitions of this type and its super-types
1088 # This function is used mainly internally.
1090 # REQUIRE: `not self.need_anchor`
1091 fun collect_mclassdefs
(mmodule
: MModule): Set[MClassDef] is abstract
1093 # Compute all the super-classes.
1094 # This function is used mainly internally.
1096 # REQUIRE: `not self.need_anchor`
1097 fun collect_mclasses
(mmodule
: MModule): Set[MClass] is abstract
1099 # Compute all the declared super-types.
1100 # Super-types are returned as declared in the classdefs (verbatim).
1101 # This function is used mainly internally.
1103 # REQUIRE: `not self.need_anchor`
1104 fun collect_mtypes
(mmodule
: MModule): Set[MClassType] is abstract
1106 # Is the property in self for a given module
1107 # This method does not filter visibility or whatever
1109 # REQUIRE: `not self.need_anchor`
1110 fun has_mproperty
(mmodule
: MModule, mproperty
: MProperty): Bool
1112 assert not self.need_anchor
1113 return self.collect_mclassdefs
(mmodule
).has
(mproperty
.intro_mclassdef
)
1117 # A type based on a class.
1119 # `MClassType` have properties (see `has_mproperty`).
1123 # The associated class
1126 redef fun model
do return self.mclass
.intro_mmodule
.model
1128 # TODO: private init because strongly bounded to its mclass. see `mclass.mclass_type`
1130 # The formal arguments of the type
1131 # ENSURE: `result.length == self.mclass.arity`
1132 var arguments
= new Array[MType]
1134 redef fun to_s
do return mclass
.to_s
1136 redef fun full_name
do return mclass
.full_name
1138 redef fun c_name
do return mclass
.c_name
1140 redef fun need_anchor
do return false
1142 redef fun anchor_to
(mmodule
: MModule, anchor
: MClassType): MClassType
1144 return super.as(MClassType)
1147 redef fun resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule, cleanup_virtual
: Bool): MClassType do return self
1149 redef fun can_resolve_for
(mtype
, anchor
, mmodule
) do return true
1151 redef fun collect_mclassdefs
(mmodule
)
1153 assert not self.need_anchor
1154 var cache
= self.collect_mclassdefs_cache
1155 if not cache
.has_key
(mmodule
) then
1156 self.collect_things
(mmodule
)
1158 return cache
[mmodule
]
1161 redef fun collect_mclasses
(mmodule
)
1163 if collect_mclasses_last_module
== mmodule
then return collect_mclasses_last_module_cache
1164 assert not self.need_anchor
1165 var cache
= self.collect_mclasses_cache
1166 if not cache
.has_key
(mmodule
) then
1167 self.collect_things
(mmodule
)
1169 var res
= cache
[mmodule
]
1170 collect_mclasses_last_module
= mmodule
1171 collect_mclasses_last_module_cache
= res
1175 private var collect_mclasses_last_module
: nullable MModule = null
1176 private var collect_mclasses_last_module_cache
: Set[MClass] is noinit
1178 redef fun collect_mtypes
(mmodule
)
1180 assert not self.need_anchor
1181 var cache
= self.collect_mtypes_cache
1182 if not cache
.has_key
(mmodule
) then
1183 self.collect_things
(mmodule
)
1185 return cache
[mmodule
]
1188 # common implementation for `collect_mclassdefs`, `collect_mclasses`, and `collect_mtypes`.
1189 private fun collect_things
(mmodule
: MModule)
1191 var res
= new HashSet[MClassDef]
1192 var seen
= new HashSet[MClass]
1193 var types
= new HashSet[MClassType]
1194 seen
.add
(self.mclass
)
1195 var todo
= [self.mclass
]
1196 while not todo
.is_empty
do
1197 var mclass
= todo
.pop
1198 #print "process {mclass}"
1199 for mclassdef
in mclass
.mclassdefs
do
1200 if not mmodule
.in_importation
<= mclassdef
.mmodule
then continue
1201 #print " process {mclassdef}"
1203 for supertype
in mclassdef
.supertypes
do
1204 types
.add
(supertype
)
1205 var superclass
= supertype
.mclass
1206 if seen
.has
(superclass
) then continue
1207 #print " add {superclass}"
1208 seen
.add
(superclass
)
1209 todo
.add
(superclass
)
1213 collect_mclassdefs_cache
[mmodule
] = res
1214 collect_mclasses_cache
[mmodule
] = seen
1215 collect_mtypes_cache
[mmodule
] = types
1218 private var collect_mclassdefs_cache
= new HashMap[MModule, Set[MClassDef]]
1219 private var collect_mclasses_cache
= new HashMap[MModule, Set[MClass]]
1220 private var collect_mtypes_cache
= new HashMap[MModule, Set[MClassType]]
1224 # A type based on a generic class.
1225 # A generic type a just a class with additional formal generic arguments.
1231 # TODO: private init because strongly bounded to its mclass. see `mclass.get_mtype`
1235 assert self.mclass
.arity
== arguments
.length
1237 self.need_anchor
= false
1238 for t
in arguments
do
1239 if t
.need_anchor
then
1240 self.need_anchor
= true
1245 self.to_s
= "{mclass}[{arguments.join(", ")}]"
1248 # The short-name of the class, then the full-name of each type arguments within brackets.
1249 # Example: `"Map[String, List[Int]]"`
1250 redef var to_s
: String is noinit
1252 # The full-name of the class, then the full-name of each type arguments within brackets.
1253 # Example: `"standard::Map[standard::String, standard::List[standard::Int]]"`
1254 redef var full_name
is lazy
do
1255 var args
= new Array[String]
1256 for t
in arguments
do
1257 args
.add t
.full_name
1259 return "{mclass.full_name}[{args.join(", ")}]"
1262 redef var c_name
is lazy
do
1263 var res
= mclass
.c_name
1264 # Note: because the arity is known, a prefix notation is enough
1265 for t
in arguments
do
1272 redef var need_anchor
: Bool is noinit
1274 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1276 if not need_anchor
then return self
1277 assert can_resolve_for
(mtype
, anchor
, mmodule
)
1278 var types
= new Array[MType]
1279 for t
in arguments
do
1280 types
.add
(t
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
))
1282 return mclass
.get_mtype
(types
)
1285 redef fun can_resolve_for
(mtype
, anchor
, mmodule
)
1287 if not need_anchor
then return true
1288 for t
in arguments
do
1289 if not t
.can_resolve_for
(mtype
, anchor
, mmodule
) then return false
1298 for a
in self.arguments
do
1300 if d
> dmax
then dmax
= d
1308 for a
in self.arguments
do
1315 # A formal type (either virtual of parametric).
1317 # The main issue with formal types is that they offer very little information on their own
1318 # and need a context (anchor and mmodule) to be useful.
1319 abstract class MFormalType
1322 redef var as_notnull
= new MNotNullType(self) is lazy
1325 # A virtual formal type.
1329 # The property associated with the type.
1330 # Its the definitions of this property that determine the bound or the virtual type.
1331 var mproperty
: MVirtualTypeProp
1333 redef fun model
do return self.mproperty
.intro_mclassdef
.mmodule
.model
1335 redef fun lookup_bound
(mmodule
: MModule, resolved_receiver
: MType): MType
1337 return lookup_single_definition
(mmodule
, resolved_receiver
).bound
.as(not null)
1340 private fun lookup_single_definition
(mmodule
: MModule, resolved_receiver
: MType): MVirtualTypeDef
1342 assert not resolved_receiver
.need_anchor
1343 var props
= self.mproperty
.lookup_definitions
(mmodule
, resolved_receiver
)
1344 if props
.is_empty
then
1346 else if props
.length
== 1 then
1349 var types
= new ArraySet[MType]
1350 var res
= props
.first
1352 types
.add
(p
.bound
.as(not null))
1353 if not res
.is_fixed
then res
= p
1355 if types
.length
== 1 then
1361 # A VT is fixed when:
1362 # * the VT is (re-)defined with the annotation `is fixed`
1363 # * the VT is (indirectly) bound to an enum class (see `enum_kind`) since there is no subtype possible
1364 # * the receiver is an enum class since there is no subtype possible
1365 redef fun lookup_fixed
(mmodule
: MModule, resolved_receiver
: MType): MType
1367 assert not resolved_receiver
.need_anchor
1368 resolved_receiver
= resolved_receiver
.undecorate
1369 assert resolved_receiver
isa MClassType # It is the only remaining type
1371 var prop
= lookup_single_definition
(mmodule
, resolved_receiver
)
1372 var res
= prop
.bound
.as(not null)
1374 # Recursively lookup the fixed result
1375 res
= res
.lookup_fixed
(mmodule
, resolved_receiver
)
1377 # 1. For a fixed VT, return the resolved bound
1378 if prop
.is_fixed
then return res
1380 # 2. For a enum boud, return the bound
1381 if res
isa MClassType and res
.mclass
.kind
== enum_kind
then return res
1383 # 3. for a enum receiver return the bound
1384 if resolved_receiver
.mclass
.kind
== enum_kind
then return res
1389 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1391 if not cleanup_virtual
then return self
1392 assert can_resolve_for
(mtype
, anchor
, mmodule
)
1393 # self is a virtual type declared (or inherited) in mtype
1394 # The point of the function it to get the bound of the virtual type that make sense for mtype
1395 # But because mtype is maybe a virtual/formal type, we need to get a real receiver first
1396 #print "{class_name}: {self}/{mtype}/{anchor}?"
1397 var resolved_receiver
1398 if mtype
.need_anchor
then
1399 assert anchor
!= null
1400 resolved_receiver
= mtype
.resolve_for
(anchor
, null, mmodule
, true)
1402 resolved_receiver
= mtype
1404 # Now, we can get the bound
1405 var verbatim_bound
= lookup_bound
(mmodule
, resolved_receiver
)
1406 # The bound is exactly as declared in the "type" property, so we must resolve it again
1407 var res
= verbatim_bound
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1412 redef fun can_resolve_for
(mtype
, anchor
, mmodule
)
1414 if mtype
.need_anchor
then
1415 assert anchor
!= null
1416 mtype
= mtype
.anchor_to
(mmodule
, anchor
)
1418 return mtype
.has_mproperty
(mmodule
, mproperty
)
1421 redef fun to_s
do return self.mproperty
.to_s
1423 redef fun full_name
do return self.mproperty
.full_name
1425 redef fun c_name
do return self.mproperty
.c_name
1428 # The type associated to a formal parameter generic type of a class
1430 # Each parameter type is associated to a specific class.
1431 # It means that all refinements of a same class "share" the parameter type,
1432 # but that a generic subclass has its own parameter types.
1434 # However, in the sense of the meta-model, a parameter type of a class is
1435 # a valid type in a subclass. The "in the sense of the meta-model" is
1436 # important because, in the Nit language, the programmer cannot refers
1437 # directly to the parameter types of the super-classes.
1442 # fun e: E is abstract
1448 # In the class definition B[F], `F` is a valid type but `E` is not.
1449 # However, `self.e` is a valid method call, and the signature of `e` is
1452 # Note that parameter types are shared among class refinements.
1453 # Therefore parameter only have an internal name (see `to_s` for details).
1454 class MParameterType
1457 # The generic class where the parameter belong
1460 redef fun model
do return self.mclass
.intro_mmodule
.model
1462 # The position of the parameter (0 for the first parameter)
1463 # FIXME: is `position` a better name?
1468 redef fun to_s
do return name
1470 redef var full_name
is lazy
do return "{mclass.full_name}::{name}"
1472 redef var c_name
is lazy
do return mclass
.c_name
+ "__" + "#{name}".to_cmangle
1474 redef fun lookup_bound
(mmodule
: MModule, resolved_receiver
: MType): MType
1476 assert not resolved_receiver
.need_anchor
1477 resolved_receiver
= resolved_receiver
.undecorate
1478 assert resolved_receiver
isa MClassType # It is the only remaining type
1479 var goalclass
= self.mclass
1480 if resolved_receiver
.mclass
== goalclass
then
1481 return resolved_receiver
.arguments
[self.rank
]
1483 var supertypes
= resolved_receiver
.collect_mtypes
(mmodule
)
1484 for t
in supertypes
do
1485 if t
.mclass
== goalclass
then
1486 # Yeah! c specialize goalclass with a "super `t'". So the question is what is the argument of f
1487 # FIXME: Here, we stop on the first goal. Should we check others and detect inconsistencies?
1488 var res
= t
.arguments
[self.rank
]
1495 # A PT is fixed when:
1496 # * Its bound is a enum class (see `enum_kind`).
1497 # The PT is just useless, but it is still a case.
1498 # * More usually, the `resolved_receiver` is a subclass of `self.mclass`,
1499 # so it is necessarily fixed in a `super` clause, either with a normal type
1500 # or with another PT.
1501 # See `resolve_for` for examples about related issues.
1502 redef fun lookup_fixed
(mmodule
: MModule, resolved_receiver
: MType): MType
1504 assert not resolved_receiver
.need_anchor
1505 resolved_receiver
= resolved_receiver
.undecorate
1506 assert resolved_receiver
isa MClassType # It is the only remaining type
1507 var res
= self.resolve_for
(resolved_receiver
.mclass
.mclass_type
, resolved_receiver
, mmodule
, false)
1511 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1513 assert can_resolve_for
(mtype
, anchor
, mmodule
)
1514 #print "{class_name}: {self}/{mtype}/{anchor}?"
1516 if mtype
isa MGenericType and mtype
.mclass
== self.mclass
then
1517 var res
= mtype
.arguments
[self.rank
]
1518 if anchor
!= null and res
.need_anchor
then
1519 # Maybe the result can be resolved more if are bound to a final class
1520 var r2
= res
.anchor_to
(mmodule
, anchor
)
1521 if r2
isa MClassType and r2
.mclass
.kind
== enum_kind
then return r2
1526 # self is a parameter type of mtype (or of a super-class of mtype)
1527 # The point of the function it to get the bound of the virtual type that make sense for mtype
1528 # But because mtype is maybe a virtual/formal type, we need to get a real receiver first
1529 # FIXME: What happens here is far from clear. Thus this part must be validated and clarified
1530 var resolved_receiver
1531 if mtype
.need_anchor
then
1532 assert anchor
!= null
1533 resolved_receiver
= mtype
.resolve_for
(anchor
.mclass
.mclass_type
, anchor
, mmodule
, true)
1535 resolved_receiver
= mtype
1537 if resolved_receiver
isa MNullableType then resolved_receiver
= resolved_receiver
.mtype
1538 if resolved_receiver
isa MParameterType then
1539 assert resolved_receiver
.mclass
== anchor
.mclass
1540 resolved_receiver
= anchor
.arguments
[resolved_receiver
.rank
]
1541 if resolved_receiver
isa MNullableType then resolved_receiver
= resolved_receiver
.mtype
1543 assert resolved_receiver
isa MClassType # It is the only remaining type
1545 # Eh! The parameter is in the current class.
1546 # So we return the corresponding argument, no mater what!
1547 if resolved_receiver
.mclass
== self.mclass
then
1548 var res
= resolved_receiver
.arguments
[self.rank
]
1549 #print "{class_name}: {self}/{mtype}/{anchor} -> direct {res}"
1553 if resolved_receiver
.need_anchor
then
1554 assert anchor
!= null
1555 resolved_receiver
= resolved_receiver
.resolve_for
(anchor
, null, mmodule
, false)
1557 # Now, we can get the bound
1558 var verbatim_bound
= lookup_bound
(mmodule
, resolved_receiver
)
1559 # The bound is exactly as declared in the "type" property, so we must resolve it again
1560 var res
= verbatim_bound
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1562 #print "{class_name}: {self}/{mtype}/{anchor} -> indirect {res}"
1567 redef fun can_resolve_for
(mtype
, anchor
, mmodule
)
1569 if mtype
.need_anchor
then
1570 assert anchor
!= null
1571 mtype
= mtype
.anchor_to
(mmodule
, anchor
)
1573 return mtype
.collect_mclassdefs
(mmodule
).has
(mclass
.intro
)
1577 # A type that decorates another type.
1579 # The point of this class is to provide a common implementation of sevices that just forward to the original type.
1580 # Specific decorator are expected to redefine (or to extend) the default implementation as this suit them.
1581 abstract class MProxyType
1586 redef fun model
do return self.mtype
.model
1587 redef fun need_anchor
do return mtype
.need_anchor
1588 redef fun as_nullable
do return mtype
.as_nullable
1589 redef fun as_notnull
do return mtype
.as_notnull
1590 redef fun undecorate
do return mtype
.undecorate
1591 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1593 var res
= self.mtype
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1597 redef fun can_resolve_for
(mtype
, anchor
, mmodule
)
1599 return self.mtype
.can_resolve_for
(mtype
, anchor
, mmodule
)
1602 redef fun lookup_fixed
(mmodule
, resolved_receiver
)
1604 var t
= mtype
.lookup_fixed
(mmodule
, resolved_receiver
)
1608 redef fun depth
do return self.mtype
.depth
1610 redef fun length
do return self.mtype
.length
1612 redef fun collect_mclassdefs
(mmodule
)
1614 assert not self.need_anchor
1615 return self.mtype
.collect_mclassdefs
(mmodule
)
1618 redef fun collect_mclasses
(mmodule
)
1620 assert not self.need_anchor
1621 return self.mtype
.collect_mclasses
(mmodule
)
1624 redef fun collect_mtypes
(mmodule
)
1626 assert not self.need_anchor
1627 return self.mtype
.collect_mtypes
(mmodule
)
1631 # A type prefixed with "nullable"
1637 self.to_s
= "nullable {mtype}"
1640 redef var to_s
: String is noinit
1642 redef var full_name
is lazy
do return "nullable {mtype.full_name}"
1644 redef var c_name
is lazy
do return "nullable__{mtype.c_name}"
1646 redef fun as_nullable
do return self
1647 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1650 return res
.as_nullable
1653 # Efficiently returns `mtype.lookup_fixed(mmodule, resolved_receiver).as_nullable`
1654 redef fun lookup_fixed
(mmodule
, resolved_receiver
)
1657 if t
== mtype
then return self
1658 return t
.as_nullable
1662 # A non-null version of a formal type.
1664 # When a formal type in bounded to a nullable type, this is the type of the not null version of it.
1668 redef fun to_s
do return "not null {mtype}"
1669 redef var full_name
is lazy
do return "not null {mtype.full_name}"
1670 redef var c_name
is lazy
do return "notnull__{mtype.c_name}"
1672 redef fun as_notnull
do return self
1674 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1677 return res
.as_notnull
1680 # Efficiently returns `mtype.lookup_fixed(mmodule, resolved_receiver).as_notnull`
1681 redef fun lookup_fixed
(mmodule
, resolved_receiver
)
1684 if t
== mtype
then return self
1689 # The type of the only value null
1691 # The is only one null type per model, see `MModel::null_type`.
1694 redef var model
: Model
1695 redef fun to_s
do return "null"
1696 redef fun full_name
do return "null"
1697 redef fun c_name
do return "null"
1698 redef fun as_nullable
do return self
1701 redef fun as_notnull
do abort # sorry...
1702 redef fun need_anchor
do return false
1703 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
) do return self
1704 redef fun can_resolve_for
(mtype
, anchor
, mmodule
) do return true
1706 redef fun collect_mclassdefs
(mmodule
) do return new HashSet[MClassDef]
1708 redef fun collect_mclasses
(mmodule
) do return new HashSet[MClass]
1710 redef fun collect_mtypes
(mmodule
) do return new HashSet[MClassType]
1713 # A signature of a method
1717 # The each parameter (in order)
1718 var mparameters
: Array[MParameter]
1720 # The return type (null for a procedure)
1721 var return_mtype
: nullable MType
1726 var t
= self.return_mtype
1727 if t
!= null then dmax
= t
.depth
1728 for p
in mparameters
do
1729 var d
= p
.mtype
.depth
1730 if d
> dmax
then dmax
= d
1738 var t
= self.return_mtype
1739 if t
!= null then res
+= t
.length
1740 for p
in mparameters
do
1741 res
+= p
.mtype
.length
1746 # REQUIRE: 1 <= mparameters.count p -> p.is_vararg
1749 var vararg_rank
= -1
1750 for i
in [0..mparameters
.length
[ do
1751 var parameter
= mparameters
[i
]
1752 if parameter
.is_vararg
then
1753 assert vararg_rank
== -1
1757 self.vararg_rank
= vararg_rank
1760 # The rank of the ellipsis (`...`) for vararg (starting from 0).
1761 # value is -1 if there is no vararg.
1762 # Example: for "(a: Int, b: Bool..., c: Char)" #-> vararg_rank=1
1763 var vararg_rank
: Int is noinit
1765 # The number of parameters
1766 fun arity
: Int do return mparameters
.length
1768 # The number of non-default parameters
1770 # The number of default parameters is then `arity-min_arity`.
1772 # Note that there cannot be both varargs and default prameters, thus
1773 # if `vararg_rank != -1` then `min_arity` == `arity`
1776 if vararg_rank
!= -1 then return arity
1778 for p
in mparameters
do
1779 if not p
.is_default
then res
+= 1
1786 var b
= new FlatBuffer
1787 if not mparameters
.is_empty
then
1789 for i
in [0..mparameters
.length
[ do
1790 var mparameter
= mparameters
[i
]
1791 if i
> 0 then b
.append
(", ")
1792 b
.append
(mparameter
.name
)
1794 b
.append
(mparameter
.mtype
.to_s
)
1795 if mparameter
.is_vararg
then
1801 var ret
= self.return_mtype
1809 redef fun resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule, cleanup_virtual
: Bool): MSignature
1811 var params
= new Array[MParameter]
1812 for p
in self.mparameters
do
1813 params
.add
(p
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
))
1815 var ret
= self.return_mtype
1817 ret
= ret
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1819 var res
= new MSignature(params
, ret
)
1824 # A parameter in a signature
1828 # The name of the parameter
1829 redef var name
: String
1831 # The static type of the parameter
1834 # Is the parameter a vararg?
1837 # Is the parameter a default one?
1838 var is_default
: Bool
1843 return "{name}: {mtype}..."
1845 return "{name}: {mtype}"
1849 # Returns a new parameter with the `mtype` resolved.
1850 # See `MType::resolve_for` for details.
1851 fun resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule, cleanup_virtual
: Bool): MParameter
1853 if not self.mtype
.need_anchor
then return self
1854 var newtype
= self.mtype
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1855 var res
= new MParameter(self.name
, newtype
, self.is_vararg
, self.is_default
)
1859 redef fun model
do return mtype
.model
1862 # A service (global property) that generalize method, attribute, etc.
1864 # `MProperty` are global to the model; it means that a `MProperty` is not bound
1865 # to a specific `MModule` nor a specific `MClass`.
1867 # A MProperty gather definitions (see `mpropdefs`) ; one for the introduction
1868 # and the other in subclasses and in refinements.
1870 # A `MProperty` is used to denotes services in polymorphic way (ie. independent
1871 # of any dynamic type).
1872 # For instance, a call site "x.foo" is associated to a `MProperty`.
1873 abstract class MProperty
1876 # The associated MPropDef subclass.
1877 # The two specialization hierarchy are symmetric.
1878 type MPROPDEF: MPropDef
1880 # The classdef that introduce the property
1881 # While a property is not bound to a specific module, or class,
1882 # the introducing mclassdef is used for naming and visibility
1883 var intro_mclassdef
: MClassDef
1885 # The (short) name of the property
1886 redef var name
: String
1888 # The canonical name of the property.
1890 # It is the short-`name` prefixed by the short-name of the class and the full-name of the module.
1891 # Example: "my_project::my_module::MyClass::my_method"
1892 redef var full_name
is lazy
do
1893 return "{intro_mclassdef.mmodule.namespace_for(visibility)}::{intro_mclassdef.mclass.name}::{name}"
1896 redef var c_name
is lazy
do
1897 # FIXME use `namespace_for`
1898 return "{intro_mclassdef.mmodule.c_name}__{intro_mclassdef.mclass.name.to_cmangle}__{name.to_cmangle}"
1901 # The visibility of the property
1902 var visibility
: MVisibility
1904 # Is the property usable as an initializer?
1905 var is_autoinit
= false is writable
1909 intro_mclassdef
.intro_mproperties
.add
(self)
1910 var model
= intro_mclassdef
.mmodule
.model
1911 model
.mproperties_by_name
.add_one
(name
, self)
1912 model
.mproperties
.add
(self)
1915 # All definitions of the property.
1916 # The first is the introduction,
1917 # The other are redefinitions (in refinements and in subclasses)
1918 var mpropdefs
= new Array[MPROPDEF]
1920 # The definition that introduces the property.
1922 # Warning: such a definition may not exist in the early life of the object.
1923 # In this case, the method will abort.
1924 var intro
: MPROPDEF is noinit
1926 redef fun model
do return intro
.model
1929 redef fun to_s
do return name
1931 # Return the most specific property definitions defined or inherited by a type.
1932 # The selection knows that refinement is stronger than specialization;
1933 # however, in case of conflict more than one property are returned.
1934 # If mtype does not know mproperty then an empty array is returned.
1936 # If you want the really most specific property, then look at `lookup_first_definition`
1938 # REQUIRE: `not mtype.need_anchor` to simplify the API (no `anchor` parameter)
1939 # ENSURE: `not mtype.has_mproperty(mmodule, self) == result.is_empty`
1940 fun lookup_definitions
(mmodule
: MModule, mtype
: MType): Array[MPROPDEF]
1942 assert not mtype
.need_anchor
1943 mtype
= mtype
.undecorate
1945 var cache
= self.lookup_definitions_cache
[mmodule
, mtype
]
1946 if cache
!= null then return cache
1948 #print "select prop {mproperty} for {mtype} in {self}"
1949 # First, select all candidates
1950 var candidates
= new Array[MPROPDEF]
1951 for mpropdef
in self.mpropdefs
do
1952 # If the definition is not imported by the module, then skip
1953 if not mmodule
.in_importation
<= mpropdef
.mclassdef
.mmodule
then continue
1954 # If the definition is not inherited by the type, then skip
1955 if not mtype
.is_subtype
(mmodule
, null, mpropdef
.mclassdef
.bound_mtype
) then continue
1957 candidates
.add
(mpropdef
)
1959 # Fast track for only one candidate
1960 if candidates
.length
<= 1 then
1961 self.lookup_definitions_cache
[mmodule
, mtype
] = candidates
1965 # Second, filter the most specific ones
1966 return select_most_specific
(mmodule
, candidates
)
1969 private var lookup_definitions_cache
= new HashMap2[MModule, MType, Array[MPROPDEF]]
1971 # Return the most specific property definitions inherited by a type.
1972 # The selection knows that refinement is stronger than specialization;
1973 # however, in case of conflict more than one property are returned.
1974 # If mtype does not know mproperty then an empty array is returned.
1976 # If you want the really most specific property, then look at `lookup_next_definition`
1978 # REQUIRE: `not mtype.need_anchor` to simplify the API (no `anchor` parameter)
1979 # ENSURE: `not mtype.has_mproperty(mmodule, self) implies result.is_empty`
1980 fun lookup_super_definitions
(mmodule
: MModule, mtype
: MType): Array[MPROPDEF]
1982 assert not mtype
.need_anchor
1983 mtype
= mtype
.undecorate
1985 # First, select all candidates
1986 var candidates
= new Array[MPROPDEF]
1987 for mpropdef
in self.mpropdefs
do
1988 # If the definition is not imported by the module, then skip
1989 if not mmodule
.in_importation
<= mpropdef
.mclassdef
.mmodule
then continue
1990 # If the definition is not inherited by the type, then skip
1991 if not mtype
.is_subtype
(mmodule
, null, mpropdef
.mclassdef
.bound_mtype
) then continue
1992 # If the definition is defined by the type, then skip (we want the super, so e skip the current)
1993 if mtype
== mpropdef
.mclassdef
.bound_mtype
and mmodule
== mpropdef
.mclassdef
.mmodule
then continue
1995 candidates
.add
(mpropdef
)
1997 # Fast track for only one candidate
1998 if candidates
.length
<= 1 then return candidates
2000 # Second, filter the most specific ones
2001 return select_most_specific
(mmodule
, candidates
)
2004 # Return an array containing olny the most specific property definitions
2005 # This is an helper function for `lookup_definitions` and `lookup_super_definitions`
2006 private fun select_most_specific
(mmodule
: MModule, candidates
: Array[MPROPDEF]): Array[MPROPDEF]
2008 var res
= new Array[MPROPDEF]
2009 for pd1
in candidates
do
2010 var cd1
= pd1
.mclassdef
2013 for pd2
in candidates
do
2014 if pd2
== pd1
then continue # do not compare with self!
2015 var cd2
= pd2
.mclassdef
2017 if c2
.mclass_type
== c1
.mclass_type
then
2018 if cd2
.mmodule
.in_importation
< cd1
.mmodule
then
2019 # cd2 refines cd1; therefore we skip pd1
2023 else if cd2
.bound_mtype
.is_subtype
(mmodule
, null, cd1
.bound_mtype
) and cd2
.bound_mtype
!= cd1
.bound_mtype
then
2024 # cd2 < cd1; therefore we skip pd1
2033 if res
.is_empty
then
2034 print
"All lost! {candidates.join(", ")}"
2035 # FIXME: should be abort!
2040 # Return the most specific definition in the linearization of `mtype`.
2042 # If you want to know the next properties in the linearization,
2043 # look at `MPropDef::lookup_next_definition`.
2045 # FIXME: the linearization is still unspecified
2047 # REQUIRE: `not mtype.need_anchor` to simplify the API (no `anchor` parameter)
2048 # REQUIRE: `mtype.has_mproperty(mmodule, self)`
2049 fun lookup_first_definition
(mmodule
: MModule, mtype
: MType): MPROPDEF
2051 return lookup_all_definitions
(mmodule
, mtype
).first
2054 # Return all definitions in a linearization order
2055 # Most specific first, most general last
2057 # REQUIRE: `not mtype.need_anchor` to simplify the API (no `anchor` parameter)
2058 # REQUIRE: `mtype.has_mproperty(mmodule, self)`
2059 fun lookup_all_definitions
(mmodule
: MModule, mtype
: MType): Array[MPROPDEF]
2061 mtype
= mtype
.undecorate
2063 var cache
= self.lookup_all_definitions_cache
[mmodule
, mtype
]
2064 if cache
!= null then return cache
2066 assert not mtype
.need_anchor
2067 assert mtype
.has_mproperty
(mmodule
, self)
2069 #print "select prop {mproperty} for {mtype} in {self}"
2070 # First, select all candidates
2071 var candidates
= new Array[MPROPDEF]
2072 for mpropdef
in self.mpropdefs
do
2073 # If the definition is not imported by the module, then skip
2074 if not mmodule
.in_importation
<= mpropdef
.mclassdef
.mmodule
then continue
2075 # If the definition is not inherited by the type, then skip
2076 if not mtype
.is_subtype
(mmodule
, null, mpropdef
.mclassdef
.bound_mtype
) then continue
2078 candidates
.add
(mpropdef
)
2080 # Fast track for only one candidate
2081 if candidates
.length
<= 1 then
2082 self.lookup_all_definitions_cache
[mmodule
, mtype
] = candidates
2086 mmodule
.linearize_mpropdefs
(candidates
)
2087 candidates
= candidates
.reversed
2088 self.lookup_all_definitions_cache
[mmodule
, mtype
] = candidates
2092 private var lookup_all_definitions_cache
= new HashMap2[MModule, MType, Array[MPROPDEF]]
2099 redef type MPROPDEF: MMethodDef
2101 # Is the property defined at the top_level of the module?
2102 # Currently such a property are stored in `Object`
2103 var is_toplevel
: Bool = false is writable
2105 # Is the property a constructor?
2106 # Warning, this property can be inherited by subclasses with or without being a constructor
2107 # therefore, you should use `is_init_for` the verify if the property is a legal constructor for a given class
2108 var is_init
: Bool = false is writable
2110 # The constructor is a (the) root init with empty signature but a set of initializers
2111 var is_root_init
: Bool = false is writable
2113 # Is the property a 'new' constructor?
2114 var is_new
: Bool = false is writable
2116 # Is the property a legal constructor for a given class?
2117 # As usual, visibility is not considered.
2118 # FIXME not implemented
2119 fun is_init_for
(mclass
: MClass): Bool
2125 # A global attribute
2129 redef type MPROPDEF: MAttributeDef
2133 # A global virtual type
2134 class MVirtualTypeProp
2137 redef type MPROPDEF: MVirtualTypeDef
2139 # The formal type associated to the virtual type property
2140 var mvirtualtype
= new MVirtualType(self)
2143 # A definition of a property (local property)
2145 # Unlike `MProperty`, a `MPropDef` is a local definition that belong to a
2146 # specific class definition (which belong to a specific module)
2147 abstract class MPropDef
2150 # The associated `MProperty` subclass.
2151 # the two specialization hierarchy are symmetric
2152 type MPROPERTY: MProperty
2155 type MPROPDEF: MPropDef
2157 # The class definition where the property definition is
2158 var mclassdef
: MClassDef
2160 # The associated global property
2161 var mproperty
: MPROPERTY
2163 # The origin of the definition
2164 var location
: Location
2168 mclassdef
.mpropdefs
.add
(self)
2169 mproperty
.mpropdefs
.add
(self)
2170 if mproperty
.intro_mclassdef
== mclassdef
then
2171 assert not isset mproperty
._intro
2172 mproperty
.intro
= self
2174 self.to_s
= "{mclassdef}#{mproperty}"
2177 # Actually the name of the `mproperty`
2178 redef fun name
do return mproperty
.name
2180 # The full-name of mpropdefs combine the information about the `classdef` and the `mproperty`.
2182 # Therefore the combination of identifiers is awful,
2183 # the worst case being
2185 # * a property "p::m::A::x"
2186 # * redefined in a refinement of a class "q::n::B"
2187 # * in a module "r::o"
2188 # * so "r::o#q::n::B#p::m::A::x"
2190 # Fortunately, the full-name is simplified when entities are repeated.
2191 # For the previous case, the simplest form is "p#A#x".
2192 redef var full_name
is lazy
do
2193 var res
= new FlatBuffer
2195 # The first part is the mclassdef. Worst case is "r::o#q::n::B"
2196 res
.append mclassdef
.full_name
2200 if mclassdef
.mclass
== mproperty
.intro_mclassdef
.mclass
then
2201 # intro are unambiguous in a class
2204 # Just try to simplify each part
2205 if mclassdef
.mmodule
.mproject
!= mproperty
.intro_mclassdef
.mmodule
.mproject
then
2206 # precise "p::m" only if "p" != "r"
2207 res
.append mproperty
.intro_mclassdef
.mmodule
.full_name
2209 else if mproperty
.visibility
<= private_visibility
then
2210 # Same project ("p"=="q"), but private visibility,
2211 # does the module part ("::m") need to be displayed
2212 if mclassdef
.mmodule
.namespace_for
(mclassdef
.mclass
.visibility
) != mproperty
.intro_mclassdef
.mmodule
.mproject
then
2214 res
.append mproperty
.intro_mclassdef
.mmodule
.name
2218 if mclassdef
.mclass
!= mproperty
.intro_mclassdef
.mclass
then
2219 # precise "B" only if not the same class than "A"
2220 res
.append mproperty
.intro_mclassdef
.name
2223 # Always use the property name "x"
2224 res
.append mproperty
.name
2229 redef var c_name
is lazy
do
2230 var res
= new FlatBuffer
2231 res
.append mclassdef
.c_name
2233 if mclassdef
.mclass
== mproperty
.intro_mclassdef
.mclass
then
2234 res
.append name
.to_cmangle
2236 if mclassdef
.mmodule
!= mproperty
.intro_mclassdef
.mmodule
then
2237 res
.append mproperty
.intro_mclassdef
.mmodule
.c_name
2240 if mclassdef
.mclass
!= mproperty
.intro_mclassdef
.mclass
then
2241 res
.append mproperty
.intro_mclassdef
.name
.to_cmangle
2244 res
.append mproperty
.name
.to_cmangle
2249 redef fun model
do return mclassdef
.model
2251 # Internal name combining the module, the class and the property
2252 # Example: "mymodule#MyClass#mymethod"
2253 redef var to_s
: String is noinit
2255 # Is self the definition that introduce the property?
2256 fun is_intro
: Bool do return mproperty
.intro
== self
2258 # Return the next definition in linearization of `mtype`.
2260 # This method is used to determine what method is called by a super.
2262 # REQUIRE: `not mtype.need_anchor`
2263 fun lookup_next_definition
(mmodule
: MModule, mtype
: MType): MPROPDEF
2265 assert not mtype
.need_anchor
2267 var mpropdefs
= self.mproperty
.lookup_all_definitions
(mmodule
, mtype
)
2268 var i
= mpropdefs
.iterator
2269 while i
.is_ok
and i
.item
!= self do i
.next
2270 assert has_property
: i
.is_ok
2272 assert has_next_property
: i
.is_ok
2277 # A local definition of a method
2281 redef type MPROPERTY: MMethod
2282 redef type MPROPDEF: MMethodDef
2284 # The signature attached to the property definition
2285 var msignature
: nullable MSignature = null is writable
2287 # The signature attached to the `new` call on a root-init
2288 # This is a concatenation of the signatures of the initializers
2290 # REQUIRE `mproperty.is_root_init == (new_msignature != null)`
2291 var new_msignature
: nullable MSignature = null is writable
2293 # List of initialisers to call in root-inits
2295 # They could be setters or attributes
2297 # REQUIRE `mproperty.is_root_init == (new_msignature != null)`
2298 var initializers
= new Array[MProperty]
2300 # Is the method definition abstract?
2301 var is_abstract
: Bool = false is writable
2303 # Is the method definition intern?
2304 var is_intern
= false is writable
2306 # Is the method definition extern?
2307 var is_extern
= false is writable
2309 # An optional constant value returned in functions.
2311 # Only some specific primitife value are accepted by engines.
2312 # Is used when there is no better implementation available.
2314 # Currently used only for the implementation of the `--define`
2315 # command-line option.
2316 # SEE: module `mixin`.
2317 var constant_value
: nullable Object = null is writable
2320 # A local definition of an attribute
2324 redef type MPROPERTY: MAttribute
2325 redef type MPROPDEF: MAttributeDef
2327 # The static type of the attribute
2328 var static_mtype
: nullable MType = null is writable
2331 # A local definition of a virtual type
2332 class MVirtualTypeDef
2335 redef type MPROPERTY: MVirtualTypeProp
2336 redef type MPROPDEF: MVirtualTypeDef
2338 # The bound of the virtual type
2339 var bound
: nullable MType = null is writable
2341 # Is the bound fixed?
2342 var is_fixed
= false is writable
2349 # * `interface_kind`
2353 # Note this class is basically an enum.
2354 # FIXME: use a real enum once user-defined enums are available
2356 redef var to_s
: String
2358 # Is a constructor required?
2361 # TODO: private init because enumeration.
2363 # Can a class of kind `self` specializes a class of kine `other`?
2364 fun can_specialize
(other
: MClassKind): Bool
2366 if other
== interface_kind
then return true # everybody can specialize interfaces
2367 if self == interface_kind
or self == enum_kind
then
2368 # no other case for interfaces
2370 else if self == extern_kind
then
2371 # only compatible with themselves
2372 return self == other
2373 else if other
== enum_kind
or other
== extern_kind
then
2374 # abstract_kind and concrete_kind are incompatible
2377 # remain only abstract_kind and concrete_kind
2382 # The class kind `abstract`
2383 fun abstract_kind
: MClassKind do return once
new MClassKind("abstract class", true)
2384 # The class kind `concrete`
2385 fun concrete_kind
: MClassKind do return once
new MClassKind("class", true)
2386 # The class kind `interface`
2387 fun interface_kind
: MClassKind do return once
new MClassKind("interface", false)
2388 # The class kind `enum`
2389 fun enum_kind
: MClassKind do return once
new MClassKind("enum", false)
2390 # The class kind `extern`
2391 fun extern_kind
: MClassKind do return once
new MClassKind("extern class", false)