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
)
255 if name
== "Bool" and self.model
.get_mclasses_by_name
("Object") != null then
256 # Bool is injected because it is needed by engine to code the result
257 # of the implicit casts.
258 var c
= new MClass(self, name
, null, enum_kind
, public_visibility
)
259 var cladef
= new MClassDef(self, c
.mclass_type
, new Location(null, 0,0,0,0))
260 cladef
.set_supertypes
([object_type
])
261 cladef
.add_in_hierarchy
264 print
("Fatal Error: no primitive class {name}")
267 if cla
.length
!= 1 then
268 var msg
= "Fatal Error: more than one primitive class {name}:"
269 for c
in cla
do msg
+= " {c.full_name}"
276 # Try to get the primitive method named `name` on the type `recv`
277 fun try_get_primitive_method
(name
: String, recv
: MClass): nullable MMethod
279 var props
= self.model
.get_mproperties_by_name
(name
)
280 if props
== null then return null
281 var res
: nullable MMethod = null
282 for mprop
in props
do
283 assert mprop
isa MMethod
284 var intro
= mprop
.intro_mclassdef
285 for mclassdef
in recv
.mclassdefs
do
286 if not self.in_importation
.greaters
.has
(mclassdef
.mmodule
) then continue
287 if not mclassdef
.in_hierarchy
.greaters
.has
(intro
) then continue
290 else if res
!= mprop
then
291 print
("Fatal Error: ambigous property name '{name}'; conflict between {mprop.full_name} and {res.full_name}")
300 private class MClassDefSorter
302 redef type COMPARED: MClassDef
304 redef fun compare
(a
, b
)
308 if ca
!= cb
then return mmodule
.flatten_mclass_hierarchy
.compare
(ca
, cb
)
309 return mmodule
.model
.mclassdef_hierarchy
.compare
(a
, b
)
313 private class MPropDefSorter
315 redef type COMPARED: MPropDef
317 redef fun compare
(pa
, pb
)
323 if ca
!= cb
then return mmodule
.flatten_mclass_hierarchy
.compare
(ca
, cb
)
324 return mmodule
.model
.mclassdef_hierarchy
.compare
(a
, b
)
330 # `MClass` are global to the model; it means that a `MClass` is not bound to a
331 # specific `MModule`.
333 # This characteristic helps the reasoning about classes in a program since a
334 # single `MClass` object always denote the same class.
336 # The drawback is that classes (`MClass`) contain almost nothing by themselves.
337 # These do not really have properties nor belong to a hierarchy since the property and the
338 # hierarchy of a class depends of the refinement in the modules.
340 # Most services on classes require the precision of a module, and no one can asks what are
341 # the super-classes of a class nor what are properties of a class without precising what is
342 # the module considered.
344 # For instance, during the typing of a source-file, the module considered is the module of the file.
345 # eg. the question *is the method `foo` exists in the class `Bar`?* must be reformulated into
346 # *is the method `foo` exists in the class `Bar` in the current module?*
348 # During some global analysis, the module considered may be the main module of the program.
352 # The module that introduce the class
353 # While classes are not bound to a specific module,
354 # the introducing module is used for naming an visibility
355 var intro_mmodule
: MModule
357 # The short name of the class
358 # In Nit, the name of a class cannot evolve in refinements
359 redef var name
: String
361 # The canonical name of the class
363 # It is the name of the class prefixed by the full_name of the `intro_mmodule`
364 # Example: `"owner::module::MyClass"`
365 redef var full_name
is lazy
do
366 return "{self.intro_mmodule.namespace_for(visibility)}::{name}"
369 redef var c_name
is lazy
do
370 return "{intro_mmodule.c_namespace_for(visibility)}__{name.to_cmangle}"
373 # The number of generic formal parameters
374 # 0 if the class is not generic
375 var arity
: Int is noinit
377 # Each generic formal parameters in order.
378 # is empty if the class is not generic
379 var mparameters
= new Array[MParameterType]
381 # Initialize `mparameters` from their names.
382 protected fun setup_parameter_names
(parameter_names
: nullable Array[String]) is
385 if parameter_names
== null then
388 self.arity
= parameter_names
.length
391 # Create the formal parameter types
393 assert parameter_names
!= null
394 var mparametertypes
= new Array[MParameterType]
395 for i
in [0..arity
[ do
396 var mparametertype
= new MParameterType(self, i
, parameter_names
[i
])
397 mparametertypes
.add
(mparametertype
)
399 self.mparameters
= mparametertypes
400 var mclass_type
= new MGenericType(self, mparametertypes
)
401 self.mclass_type
= mclass_type
402 self.get_mtype_cache
[mparametertypes
] = mclass_type
404 self.mclass_type
= new MClassType(self)
408 # The kind of the class (interface, abstract class, etc.)
409 # In Nit, the kind of a class cannot evolve in refinements
412 # The visibility of the class
413 # In Nit, the visibility of a class cannot evolve in refinements
414 var visibility
: MVisibility
418 intro_mmodule
.intro_mclasses
.add
(self)
419 var model
= intro_mmodule
.model
420 model
.mclasses_by_name
.add_one
(name
, self)
421 model
.mclasses
.add
(self)
424 redef fun model
do return intro_mmodule
.model
426 # All class definitions (introduction and refinements)
427 var mclassdefs
= new Array[MClassDef]
430 redef fun to_s
do return self.name
432 # The definition that introduces the class.
434 # Warning: such a definition may not exist in the early life of the object.
435 # In this case, the method will abort.
436 var intro
: MClassDef is noinit
438 # Return the class `self` in the class hierarchy of the module `mmodule`.
440 # SEE: `MModule::flatten_mclass_hierarchy`
441 # REQUIRE: `mmodule.has_mclass(self)`
442 fun in_hierarchy
(mmodule
: MModule): POSetElement[MClass]
444 return mmodule
.flatten_mclass_hierarchy
[self]
447 # The principal static type of the class.
449 # For non-generic class, mclass_type is the only `MClassType` based
452 # For a generic class, the arguments are the formal parameters.
453 # i.e.: for the class Array[E:Object], the `mclass_type` is Array[E].
454 # If you want Array[Object] the see `MClassDef::bound_mtype`
456 # For generic classes, the mclass_type is also the way to get a formal
457 # generic parameter type.
459 # To get other types based on a generic class, see `get_mtype`.
461 # ENSURE: `mclass_type.mclass == self`
462 var mclass_type
: MClassType is noinit
464 # Return a generic type based on the class
465 # Is the class is not generic, then the result is `mclass_type`
467 # REQUIRE: `mtype_arguments.length == self.arity`
468 fun get_mtype
(mtype_arguments
: Array[MType]): MClassType
470 assert mtype_arguments
.length
== self.arity
471 if self.arity
== 0 then return self.mclass_type
472 var res
= get_mtype_cache
.get_or_null
(mtype_arguments
)
473 if res
!= null then return res
474 res
= new MGenericType(self, mtype_arguments
)
475 self.get_mtype_cache
[mtype_arguments
.to_a
] = res
479 private var get_mtype_cache
= new HashMap[Array[MType], MGenericType]
481 # Is there a `new` factory to allow the pseudo instantiation?
482 var has_new_factory
= false is writable
486 # A definition (an introduction or a refinement) of a class in a module
488 # A `MClassDef` is associated with an explicit (or almost) definition of a
489 # class. Unlike `MClass`, a `MClassDef` is a local definition that belong to
490 # a specific class and a specific module, and contains declarations like super-classes
493 # It is the class definitions that are the backbone of most things in the model:
494 # ClassDefs are defined with regard with other classdefs.
495 # Refinement and specialization are combined to produce a big poset called the `Model::mclassdef_hierarchy`.
497 # Moreover, the extension and the intention of types is defined by looking at the MClassDefs.
501 # The module where the definition is
504 # The associated `MClass`
505 var mclass
: MClass is noinit
507 # The bounded type associated to the mclassdef
509 # For a non-generic class, `bound_mtype` and `mclass.mclass_type`
513 # For the classdef Array[E: Object], the bound_mtype is Array[Object].
514 # If you want Array[E], then see `mclass.mclass_type`
516 # ENSURE: `bound_mtype.mclass == self.mclass`
517 var bound_mtype
: MClassType
519 # The origin of the definition
520 var location
: Location
522 # Internal name combining the module and the class
523 # Example: "mymodule#MyClass"
524 redef var to_s
: String is noinit
528 self.mclass
= bound_mtype
.mclass
529 mmodule
.mclassdefs
.add
(self)
530 mclass
.mclassdefs
.add
(self)
531 if mclass
.intro_mmodule
== mmodule
then
532 assert not isset mclass
._intro
535 self.to_s
= "{mmodule}#{mclass}"
538 # Actually the name of the `mclass`
539 redef fun name
do return mclass
.name
541 # The module and class name separated by a '#'.
543 # The short-name of the class is used for introduction.
544 # Example: "my_module#MyClass"
546 # The full-name of the class is used for refinement.
547 # Example: "my_module#intro_module::MyClass"
548 redef var full_name
is lazy
do
551 # private gives 'p::m#A'
552 return "{mmodule.namespace_for(mclass.visibility)}#{mclass.name}"
553 else if mclass
.intro_mmodule
.mproject
!= mmodule
.mproject
then
554 # public gives 'q::n#p::A'
555 # private gives 'q::n#p::m::A'
556 return "{mmodule.full_name}#{mclass.full_name}"
557 else if mclass
.visibility
> private_visibility
then
558 # public gives 'p::n#A'
559 return "{mmodule.full_name}#{mclass.name}"
561 # private gives 'p::n#::m::A' (redundant p is omitted)
562 return "{mmodule.full_name}#::{mclass.intro_mmodule.name}::{mclass.name}"
566 redef var c_name
is lazy
do
568 return "{mmodule.c_namespace_for(mclass.visibility)}___{mclass.c_name}"
569 else if mclass
.intro_mmodule
.mproject
== mmodule
.mproject
and mclass
.visibility
> private_visibility
then
570 return "{mmodule.c_name}___{mclass.name.to_cmangle}"
572 return "{mmodule.c_name}___{mclass.c_name}"
576 redef fun model
do return mmodule
.model
578 # All declared super-types
579 # FIXME: quite ugly but not better idea yet
580 var supertypes
= new Array[MClassType]
582 # Register some super-types for the class (ie "super SomeType")
584 # The hierarchy must not already be set
585 # REQUIRE: `self.in_hierarchy == null`
586 fun set_supertypes
(supertypes
: Array[MClassType])
588 assert unique_invocation
: self.in_hierarchy
== null
589 var mmodule
= self.mmodule
590 var model
= mmodule
.model
591 var mtype
= self.bound_mtype
593 for supertype
in supertypes
do
594 self.supertypes
.add
(supertype
)
596 # Register in full_type_specialization_hierarchy
597 model
.full_mtype_specialization_hierarchy
.add_edge
(mtype
, supertype
)
598 # Register in intro_type_specialization_hierarchy
599 if mclass
.intro_mmodule
== mmodule
and supertype
.mclass
.intro_mmodule
== mmodule
then
600 model
.intro_mtype_specialization_hierarchy
.add_edge
(mtype
, supertype
)
606 # Collect the super-types (set by set_supertypes) to build the hierarchy
608 # This function can only invoked once by class
609 # REQUIRE: `self.in_hierarchy == null`
610 # ENSURE: `self.in_hierarchy != null`
613 assert unique_invocation
: self.in_hierarchy
== null
614 var model
= mmodule
.model
615 var res
= model
.mclassdef_hierarchy
.add_node
(self)
616 self.in_hierarchy
= res
617 var mtype
= self.bound_mtype
619 # Here we need to connect the mclassdef to its pairs in the mclassdef_hierarchy
620 # The simpliest way is to attach it to collect_mclassdefs
621 for mclassdef
in mtype
.collect_mclassdefs
(mmodule
) do
622 res
.poset
.add_edge
(self, mclassdef
)
626 # The view of the class definition in `mclassdef_hierarchy`
627 var in_hierarchy
: nullable POSetElement[MClassDef] = null
629 # Is the definition the one that introduced `mclass`?
630 fun is_intro
: Bool do return mclass
.intro
== self
632 # All properties introduced by the classdef
633 var intro_mproperties
= new Array[MProperty]
635 # All property definitions in the class (introductions and redefinitions)
636 var mpropdefs
= new Array[MPropDef]
639 # A global static type
641 # MType are global to the model; it means that a `MType` is not bound to a
642 # specific `MModule`.
643 # This characteristic helps the reasoning about static types in a program
644 # since a single `MType` object always denote the same type.
646 # However, because a `MType` is global, it does not really have properties
647 # nor have subtypes to a hierarchy since the property and the class hierarchy
648 # depends of a module.
649 # Moreover, virtual types an formal generic parameter types also depends on
650 # a receiver to have sense.
652 # Therefore, most method of the types require a module and an anchor.
653 # The module is used to know what are the classes and the specialization
655 # The anchor is used to know what is the bound of the virtual types and formal
656 # generic parameter types.
658 # MType are not directly usable to get properties. See the `anchor_to` method
659 # and the `MClassType` class.
661 # FIXME: the order of the parameters is not the best. We mus pick on from:
662 # * foo(mmodule, anchor, othertype)
663 # * foo(othertype, anchor, mmodule)
664 # * foo(anchor, mmodule, othertype)
665 # * foo(othertype, mmodule, anchor)
669 redef fun name
do return to_s
671 # Return true if `self` is an subtype of `sup`.
672 # The typing is done using the standard typing policy of Nit.
674 # REQUIRE: `anchor == null implies not self.need_anchor and not sup.need_anchor`
675 # REQUIRE: `anchor != null implies self.can_resolve_for(anchor, null, mmodule) and sup.can_resolve_for(anchor, null, mmodule)`
676 fun is_subtype
(mmodule
: MModule, anchor
: nullable MClassType, sup
: MType): Bool
679 if sub
== sup
then return true
681 #print "1.is {sub} a {sup}? ===="
683 if anchor
== null then
684 assert not sub
.need_anchor
685 assert not sup
.need_anchor
687 # First, resolve the formal types to the simplest equivalent forms in the receiver
688 assert sub
.can_resolve_for
(anchor
, null, mmodule
)
689 sub
= sub
.lookup_fixed
(mmodule
, anchor
)
690 assert sup
.can_resolve_for
(anchor
, null, mmodule
)
691 sup
= sup
.lookup_fixed
(mmodule
, anchor
)
694 # Does `sup` accept null or not?
695 # Discard the nullable marker if it exists
696 var sup_accept_null
= false
697 if sup
isa MNullableType then
698 sup_accept_null
= true
700 else if sup
isa MNotNullType then
702 else if sup
isa MNullType then
703 sup_accept_null
= true
706 # Can `sub` provide null or not?
707 # Thus we can match with `sup_accept_null`
708 # Also discard the nullable marker if it exists
709 var sub_reject_null
= false
710 if sub
isa MNullableType then
711 if not sup_accept_null
then return false
713 else if sub
isa MNotNullType then
714 sub_reject_null
= true
716 else if sub
isa MNullType then
717 return sup_accept_null
719 # Now the case of direct null and nullable is over.
721 # If `sub` is a formal type, then it is accepted if its bound is accepted
722 while sub
isa MFormalType do
723 #print "3.is {sub} a {sup}?"
725 # A unfixed formal type can only accept itself
726 if sub
== sup
then return true
728 assert anchor
!= null
729 sub
= sub
.lookup_bound
(mmodule
, anchor
)
730 if sub_reject_null
then sub
= sub
.as_notnull
732 #print "3.is {sub} a {sup}?"
734 # Manage the second layer of null/nullable
735 if sub
isa MNullableType then
736 if not sup_accept_null
and not sub_reject_null
then return false
738 else if sub
isa MNotNullType then
739 sub_reject_null
= true
741 else if sub
isa MNullType then
742 return sup_accept_null
745 #print "4.is {sub} a {sup}? <- no more resolution"
747 assert sub
isa MClassType else print
"{sub} <? {sub}" # It is the only remaining type
749 # A unfixed formal type can only accept itself
750 if sup
isa MFormalType then
754 if sup
isa MNullType then
755 # `sup` accepts only null
759 assert sup
isa MClassType # It is the only remaining type
761 # Now both are MClassType, we need to dig
763 if sub
== sup
then return true
765 if anchor
== null then anchor
= sub
# UGLY: any anchor will work
766 var resolved_sub
= sub
.anchor_to
(mmodule
, anchor
)
767 var res
= resolved_sub
.collect_mclasses
(mmodule
).has
(sup
.mclass
)
768 if res
== false then return false
769 if not sup
isa MGenericType then return true
770 var sub2
= sub
.supertype_to
(mmodule
, anchor
, sup
.mclass
)
771 assert sub2
.mclass
== sup
.mclass
772 for i
in [0..sup
.mclass
.arity
[ do
773 var sub_arg
= sub2
.arguments
[i
]
774 var sup_arg
= sup
.arguments
[i
]
775 res
= sub_arg
.is_subtype
(mmodule
, anchor
, sup_arg
)
776 if res
== false then return false
781 # The base class type on which self is based
783 # This base type is used to get property (an internally to perform
784 # unsafe type comparison).
786 # Beware: some types (like null) are not based on a class thus this
789 # Basically, this function transform the virtual types and parameter
790 # types to their bounds.
795 # class B super A end
797 # class Y super X end
806 # Map[T,U] anchor_to H #-> Map[B,Y]
808 # Explanation of the example:
809 # In H, T is set to B, because "H super G[B]", and U is bound to Y,
810 # because "redef type U: Y". Therefore, Map[T, U] is bound to
813 # ENSURE: `not self.need_anchor implies result == self`
814 # ENSURE: `not result.need_anchor`
815 fun anchor_to
(mmodule
: MModule, anchor
: MClassType): MType
817 if not need_anchor
then return self
818 assert not anchor
.need_anchor
819 # Just resolve to the anchor and clear all the virtual types
820 var res
= self.resolve_for
(anchor
, null, mmodule
, true)
821 assert not res
.need_anchor
825 # Does `self` contain a virtual type or a formal generic parameter type?
826 # In order to remove those types, you usually want to use `anchor_to`.
827 fun need_anchor
: Bool do return true
829 # Return the supertype when adapted to a class.
831 # In Nit, for each super-class of a type, there is a equivalent super-type.
837 # class H[V] super G[V, Bool] end
839 # H[Int] supertype_to G #-> G[Int, Bool]
842 # REQUIRE: `super_mclass` is a super-class of `self`
843 # REQUIRE: `self.need_anchor implies anchor != null and self.can_resolve_for(anchor, null, mmodule)`
844 # ENSURE: `result.mclass = super_mclass`
845 fun supertype_to
(mmodule
: MModule, anchor
: nullable MClassType, super_mclass
: MClass): MClassType
847 if super_mclass
.arity
== 0 then return super_mclass
.mclass_type
848 if self isa MClassType and self.mclass
== super_mclass
then return self
850 if self.need_anchor
then
851 assert anchor
!= null
852 resolved_self
= self.anchor_to
(mmodule
, anchor
)
856 var supertypes
= resolved_self
.collect_mtypes
(mmodule
)
857 for supertype
in supertypes
do
858 if supertype
.mclass
== super_mclass
then
859 # FIXME: Here, we stop on the first goal. Should we check others and detect inconsistencies?
860 return supertype
.resolve_for
(self, anchor
, mmodule
, false)
866 # Replace formals generic types in self with resolved values in `mtype`
867 # If `cleanup_virtual` is true, then virtual types are also replaced
870 # This function returns self if `need_anchor` is false.
876 # class H[F] super G[F] end
880 # * Array[E].resolve_for(H[Int]) #-> Array[Int]
881 # * Array[E].resolve_for(G[Z], X[Int]) #-> Array[Z]
883 # Explanation of the example:
884 # * Array[E].need_anchor is true because there is a formal generic parameter type E
885 # * E makes sense for H[Int] because E is a formal parameter of G and H specialize G
886 # * Since "H[F] super G[F]", E is in fact F for H
887 # * More specifically, in H[Int], E is Int
888 # * So, in H[Int], Array[E] is Array[Int]
890 # This function is mainly used to inherit a signature.
891 # Because, unlike `anchor_to`, we do not want a full resolution of
892 # a type but only an adapted version of it.
898 # fun foo(e:E):E is abstract
900 # class B super A[Int] end
903 # The signature on foo is (e: E): E
904 # If we resolve the signature for B, we get (e:Int):Int
910 # fun foo(e:E):E is abstract
914 # fun bar do a.foo(x) # <- x is here
918 # The first question is: is foo available on `a`?
920 # The static type of a is `A[Array[F]]`, that is an open type.
921 # in order to find a method `foo`, whe must look at a resolved type.
923 # A[Array[F]].anchor_to(C[nullable Object]) #-> A[Array[nullable Object]]
925 # the method `foo` exists in `A[Array[nullable Object]]`, therefore `foo` exists for `a`.
927 # The next question is: what is the accepted types for `x`?
929 # the signature of `foo` is `foo(e:E)`, thus we must resolve the type E
931 # E.resolve_for(A[Array[F]],C[nullable Object]) #-> Array[F]
933 # The resolution can be done because `E` make sense for the class A (see `can_resolve_for`)
935 # FIXME: the parameter `cleanup_virtual` is just a bad idea, but having
936 # two function instead of one seems also to be a bad idea.
938 # REQUIRE: `can_resolve_for(mtype, anchor, mmodule)`
939 # ENSURE: `not self.need_anchor implies result == self`
940 fun resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule, cleanup_virtual
: Bool): MType is abstract
942 # Resolve formal type to its verbatim bound.
943 # If the type is not formal, just return self
945 # The result is returned exactly as declared in the "type" property (verbatim).
946 # So it could be another formal type.
948 # In case of conflict, the method aborts.
949 fun lookup_bound
(mmodule
: MModule, resolved_receiver
: MType): MType do return self
951 # Resolve the formal type to its simplest equivalent form.
953 # Formal types are either free or fixed.
954 # When it is fixed, it means that it is equivalent with a simpler type.
955 # When a formal type is free, it means that it is only equivalent with itself.
956 # This method return the most simple equivalent type of `self`.
958 # This method is mainly used for subtype test in order to sanely compare fixed.
960 # By default, return self.
961 # See the redefinitions for specific behavior in each kind of type.
962 fun lookup_fixed
(mmodule
: MModule, resolved_receiver
: MType): MType do return self
964 # Can the type be resolved?
966 # In order to resolve open types, the formal types must make sence.
976 # E.can_resolve_for(A[Int]) #-> true, E make sense in A
978 # E.can_resolve_for(B[Int]) #-> false, E does not make sense in B
980 # B[E].can_resolve_for(A[F], B[Object]) #-> true,
981 # # B[E] is a red hearing only the E is important,
982 # # E make sense in A
985 # REQUIRE: `anchor != null implies not anchor.need_anchor`
986 # REQUIRE: `mtype.need_anchor implies anchor != null and mtype.can_resolve_for(anchor, null, mmodule)`
987 # ENSURE: `not self.need_anchor implies result == true`
988 fun can_resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule): Bool is abstract
990 # Return the nullable version of the type
991 # If the type is already nullable then self is returned
992 fun as_nullable
: MType
994 var res
= self.as_nullable_cache
995 if res
!= null then return res
996 res
= new MNullableType(self)
997 self.as_nullable_cache
= res
1001 # Remove the base type of a decorated (proxy) type.
1002 # Is the type is not decorated, then self is returned.
1004 # Most of the time it is used to return the not nullable version of a nullable type.
1005 # In this case, this just remove the `nullable` notation, but the result can still contains null.
1006 # For instance if `self isa MNullType` or self is a formal type bounded by a nullable type.
1007 # If you really want to exclude the `null` value, then use `as_notnull`
1008 fun undecorate
: MType
1013 # Returns the not null version of the type.
1014 # That is `self` minus the `null` value.
1016 # For most types, this return `self`.
1017 # For formal types, this returns a special `MNotNullType`
1018 fun as_notnull
: MType do return self
1020 private var as_nullable_cache
: nullable MType = null
1023 # The depth of the type seen as a tree.
1030 # Formal types have a depth of 1.
1036 # The length of the type seen as a tree.
1043 # Formal types have a length of 1.
1049 # Compute all the classdefs inherited/imported.
1050 # The returned set contains:
1051 # * the class definitions from `mmodule` and its imported modules
1052 # * the class definitions of this type and its super-types
1054 # This function is used mainly internally.
1056 # REQUIRE: `not self.need_anchor`
1057 fun collect_mclassdefs
(mmodule
: MModule): Set[MClassDef] is abstract
1059 # Compute all the super-classes.
1060 # This function is used mainly internally.
1062 # REQUIRE: `not self.need_anchor`
1063 fun collect_mclasses
(mmodule
: MModule): Set[MClass] is abstract
1065 # Compute all the declared super-types.
1066 # Super-types are returned as declared in the classdefs (verbatim).
1067 # This function is used mainly internally.
1069 # REQUIRE: `not self.need_anchor`
1070 fun collect_mtypes
(mmodule
: MModule): Set[MClassType] is abstract
1072 # Is the property in self for a given module
1073 # This method does not filter visibility or whatever
1075 # REQUIRE: `not self.need_anchor`
1076 fun has_mproperty
(mmodule
: MModule, mproperty
: MProperty): Bool
1078 assert not self.need_anchor
1079 return self.collect_mclassdefs
(mmodule
).has
(mproperty
.intro_mclassdef
)
1083 # A type based on a class.
1085 # `MClassType` have properties (see `has_mproperty`).
1089 # The associated class
1092 redef fun model
do return self.mclass
.intro_mmodule
.model
1094 # TODO: private init because strongly bounded to its mclass. see `mclass.mclass_type`
1096 # The formal arguments of the type
1097 # ENSURE: `result.length == self.mclass.arity`
1098 var arguments
= new Array[MType]
1100 redef fun to_s
do return mclass
.to_s
1102 redef fun full_name
do return mclass
.full_name
1104 redef fun c_name
do return mclass
.c_name
1106 redef fun need_anchor
do return false
1108 redef fun anchor_to
(mmodule
: MModule, anchor
: MClassType): MClassType
1110 return super.as(MClassType)
1113 redef fun resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule, cleanup_virtual
: Bool): MClassType do return self
1115 redef fun can_resolve_for
(mtype
, anchor
, mmodule
) do return true
1117 redef fun collect_mclassdefs
(mmodule
)
1119 assert not self.need_anchor
1120 var cache
= self.collect_mclassdefs_cache
1121 if not cache
.has_key
(mmodule
) then
1122 self.collect_things
(mmodule
)
1124 return cache
[mmodule
]
1127 redef fun collect_mclasses
(mmodule
)
1129 if collect_mclasses_last_module
== mmodule
then return collect_mclasses_last_module_cache
1130 assert not self.need_anchor
1131 var cache
= self.collect_mclasses_cache
1132 if not cache
.has_key
(mmodule
) then
1133 self.collect_things
(mmodule
)
1135 var res
= cache
[mmodule
]
1136 collect_mclasses_last_module
= mmodule
1137 collect_mclasses_last_module_cache
= res
1141 private var collect_mclasses_last_module
: nullable MModule = null
1142 private var collect_mclasses_last_module_cache
: Set[MClass] is noinit
1144 redef fun collect_mtypes
(mmodule
)
1146 assert not self.need_anchor
1147 var cache
= self.collect_mtypes_cache
1148 if not cache
.has_key
(mmodule
) then
1149 self.collect_things
(mmodule
)
1151 return cache
[mmodule
]
1154 # common implementation for `collect_mclassdefs`, `collect_mclasses`, and `collect_mtypes`.
1155 private fun collect_things
(mmodule
: MModule)
1157 var res
= new HashSet[MClassDef]
1158 var seen
= new HashSet[MClass]
1159 var types
= new HashSet[MClassType]
1160 seen
.add
(self.mclass
)
1161 var todo
= [self.mclass
]
1162 while not todo
.is_empty
do
1163 var mclass
= todo
.pop
1164 #print "process {mclass}"
1165 for mclassdef
in mclass
.mclassdefs
do
1166 if not mmodule
.in_importation
<= mclassdef
.mmodule
then continue
1167 #print " process {mclassdef}"
1169 for supertype
in mclassdef
.supertypes
do
1170 types
.add
(supertype
)
1171 var superclass
= supertype
.mclass
1172 if seen
.has
(superclass
) then continue
1173 #print " add {superclass}"
1174 seen
.add
(superclass
)
1175 todo
.add
(superclass
)
1179 collect_mclassdefs_cache
[mmodule
] = res
1180 collect_mclasses_cache
[mmodule
] = seen
1181 collect_mtypes_cache
[mmodule
] = types
1184 private var collect_mclassdefs_cache
= new HashMap[MModule, Set[MClassDef]]
1185 private var collect_mclasses_cache
= new HashMap[MModule, Set[MClass]]
1186 private var collect_mtypes_cache
= new HashMap[MModule, Set[MClassType]]
1190 # A type based on a generic class.
1191 # A generic type a just a class with additional formal generic arguments.
1197 # TODO: private init because strongly bounded to its mclass. see `mclass.get_mtype`
1201 assert self.mclass
.arity
== arguments
.length
1203 self.need_anchor
= false
1204 for t
in arguments
do
1205 if t
.need_anchor
then
1206 self.need_anchor
= true
1211 self.to_s
= "{mclass}[{arguments.join(", ")}]"
1214 # The short-name of the class, then the full-name of each type arguments within brackets.
1215 # Example: `"Map[String, List[Int]]"`
1216 redef var to_s
: String is noinit
1218 # The full-name of the class, then the full-name of each type arguments within brackets.
1219 # Example: `"standard::Map[standard::String, standard::List[standard::Int]]"`
1220 redef var full_name
is lazy
do
1221 var args
= new Array[String]
1222 for t
in arguments
do
1223 args
.add t
.full_name
1225 return "{mclass.full_name}[{args.join(", ")}]"
1228 redef var c_name
is lazy
do
1229 var res
= mclass
.c_name
1230 # Note: because the arity is known, a prefix notation is enough
1231 for t
in arguments
do
1238 redef var need_anchor
: Bool is noinit
1240 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1242 if not need_anchor
then return self
1243 assert can_resolve_for
(mtype
, anchor
, mmodule
)
1244 var types
= new Array[MType]
1245 for t
in arguments
do
1246 types
.add
(t
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
))
1248 return mclass
.get_mtype
(types
)
1251 redef fun can_resolve_for
(mtype
, anchor
, mmodule
)
1253 if not need_anchor
then return true
1254 for t
in arguments
do
1255 if not t
.can_resolve_for
(mtype
, anchor
, mmodule
) then return false
1264 for a
in self.arguments
do
1266 if d
> dmax
then dmax
= d
1274 for a
in self.arguments
do
1281 # A formal type (either virtual of parametric).
1283 # The main issue with formal types is that they offer very little information on their own
1284 # and need a context (anchor and mmodule) to be useful.
1285 abstract class MFormalType
1288 redef var as_notnull
= new MNotNullType(self) is lazy
1291 # A virtual formal type.
1295 # The property associated with the type.
1296 # Its the definitions of this property that determine the bound or the virtual type.
1297 var mproperty
: MVirtualTypeProp
1299 redef fun model
do return self.mproperty
.intro_mclassdef
.mmodule
.model
1301 redef fun lookup_bound
(mmodule
: MModule, resolved_receiver
: MType): MType
1303 return lookup_single_definition
(mmodule
, resolved_receiver
).bound
.as(not null)
1306 private fun lookup_single_definition
(mmodule
: MModule, resolved_receiver
: MType): MVirtualTypeDef
1308 assert not resolved_receiver
.need_anchor
1309 var props
= self.mproperty
.lookup_definitions
(mmodule
, resolved_receiver
)
1310 if props
.is_empty
then
1312 else if props
.length
== 1 then
1315 var types
= new ArraySet[MType]
1316 var res
= props
.first
1318 types
.add
(p
.bound
.as(not null))
1319 if not res
.is_fixed
then res
= p
1321 if types
.length
== 1 then
1327 # A VT is fixed when:
1328 # * the VT is (re-)defined with the annotation `is fixed`
1329 # * the VT is (indirectly) bound to an enum class (see `enum_kind`) since there is no subtype possible
1330 # * the receiver is an enum class since there is no subtype possible
1331 redef fun lookup_fixed
(mmodule
: MModule, resolved_receiver
: MType): MType
1333 assert not resolved_receiver
.need_anchor
1334 resolved_receiver
= resolved_receiver
.undecorate
1335 assert resolved_receiver
isa MClassType # It is the only remaining type
1337 var prop
= lookup_single_definition
(mmodule
, resolved_receiver
)
1338 var res
= prop
.bound
.as(not null)
1340 # Recursively lookup the fixed result
1341 res
= res
.lookup_fixed
(mmodule
, resolved_receiver
)
1343 # 1. For a fixed VT, return the resolved bound
1344 if prop
.is_fixed
then return res
1346 # 2. For a enum boud, return the bound
1347 if res
isa MClassType and res
.mclass
.kind
== enum_kind
then return res
1349 # 3. for a enum receiver return the bound
1350 if resolved_receiver
.mclass
.kind
== enum_kind
then return res
1355 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1357 if not cleanup_virtual
then return self
1358 assert can_resolve_for
(mtype
, anchor
, mmodule
)
1359 # self is a virtual type declared (or inherited) in mtype
1360 # The point of the function it to get the bound of the virtual type that make sense for mtype
1361 # But because mtype is maybe a virtual/formal type, we need to get a real receiver first
1362 #print "{class_name}: {self}/{mtype}/{anchor}?"
1363 var resolved_receiver
1364 if mtype
.need_anchor
then
1365 assert anchor
!= null
1366 resolved_receiver
= mtype
.resolve_for
(anchor
, null, mmodule
, true)
1368 resolved_receiver
= mtype
1370 # Now, we can get the bound
1371 var verbatim_bound
= lookup_bound
(mmodule
, resolved_receiver
)
1372 # The bound is exactly as declared in the "type" property, so we must resolve it again
1373 var res
= verbatim_bound
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1378 redef fun can_resolve_for
(mtype
, anchor
, mmodule
)
1380 if mtype
.need_anchor
then
1381 assert anchor
!= null
1382 mtype
= mtype
.anchor_to
(mmodule
, anchor
)
1384 return mtype
.has_mproperty
(mmodule
, mproperty
)
1387 redef fun to_s
do return self.mproperty
.to_s
1389 redef fun full_name
do return self.mproperty
.full_name
1391 redef fun c_name
do return self.mproperty
.c_name
1394 # The type associated to a formal parameter generic type of a class
1396 # Each parameter type is associated to a specific class.
1397 # It means that all refinements of a same class "share" the parameter type,
1398 # but that a generic subclass has its own parameter types.
1400 # However, in the sense of the meta-model, a parameter type of a class is
1401 # a valid type in a subclass. The "in the sense of the meta-model" is
1402 # important because, in the Nit language, the programmer cannot refers
1403 # directly to the parameter types of the super-classes.
1408 # fun e: E is abstract
1414 # In the class definition B[F], `F` is a valid type but `E` is not.
1415 # However, `self.e` is a valid method call, and the signature of `e` is
1418 # Note that parameter types are shared among class refinements.
1419 # Therefore parameter only have an internal name (see `to_s` for details).
1420 class MParameterType
1423 # The generic class where the parameter belong
1426 redef fun model
do return self.mclass
.intro_mmodule
.model
1428 # The position of the parameter (0 for the first parameter)
1429 # FIXME: is `position` a better name?
1434 redef fun to_s
do return name
1436 redef var full_name
is lazy
do return "{mclass.full_name}::{name}"
1438 redef var c_name
is lazy
do return mclass
.c_name
+ "__" + "#{name}".to_cmangle
1440 redef fun lookup_bound
(mmodule
: MModule, resolved_receiver
: MType): MType
1442 assert not resolved_receiver
.need_anchor
1443 resolved_receiver
= resolved_receiver
.undecorate
1444 assert resolved_receiver
isa MClassType # It is the only remaining type
1445 var goalclass
= self.mclass
1446 if resolved_receiver
.mclass
== goalclass
then
1447 return resolved_receiver
.arguments
[self.rank
]
1449 var supertypes
= resolved_receiver
.collect_mtypes
(mmodule
)
1450 for t
in supertypes
do
1451 if t
.mclass
== goalclass
then
1452 # Yeah! c specialize goalclass with a "super `t'". So the question is what is the argument of f
1453 # FIXME: Here, we stop on the first goal. Should we check others and detect inconsistencies?
1454 var res
= t
.arguments
[self.rank
]
1461 # A PT is fixed when:
1462 # * Its bound is a enum class (see `enum_kind`).
1463 # The PT is just useless, but it is still a case.
1464 # * More usually, the `resolved_receiver` is a subclass of `self.mclass`,
1465 # so it is necessarily fixed in a `super` clause, either with a normal type
1466 # or with another PT.
1467 # See `resolve_for` for examples about related issues.
1468 redef fun lookup_fixed
(mmodule
: MModule, resolved_receiver
: MType): MType
1470 assert not resolved_receiver
.need_anchor
1471 resolved_receiver
= resolved_receiver
.undecorate
1472 assert resolved_receiver
isa MClassType # It is the only remaining type
1473 var res
= self.resolve_for
(resolved_receiver
.mclass
.mclass_type
, resolved_receiver
, mmodule
, false)
1477 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1479 assert can_resolve_for
(mtype
, anchor
, mmodule
)
1480 #print "{class_name}: {self}/{mtype}/{anchor}?"
1482 if mtype
isa MGenericType and mtype
.mclass
== self.mclass
then
1483 var res
= mtype
.arguments
[self.rank
]
1484 if anchor
!= null and res
.need_anchor
then
1485 # Maybe the result can be resolved more if are bound to a final class
1486 var r2
= res
.anchor_to
(mmodule
, anchor
)
1487 if r2
isa MClassType and r2
.mclass
.kind
== enum_kind
then return r2
1492 # self is a parameter type of mtype (or of a super-class of mtype)
1493 # The point of the function it to get the bound of the virtual type that make sense for mtype
1494 # But because mtype is maybe a virtual/formal type, we need to get a real receiver first
1495 # FIXME: What happens here is far from clear. Thus this part must be validated and clarified
1496 var resolved_receiver
1497 if mtype
.need_anchor
then
1498 assert anchor
!= null
1499 resolved_receiver
= mtype
.resolve_for
(anchor
.mclass
.mclass_type
, anchor
, mmodule
, true)
1501 resolved_receiver
= mtype
1503 if resolved_receiver
isa MNullableType then resolved_receiver
= resolved_receiver
.mtype
1504 if resolved_receiver
isa MParameterType then
1505 assert resolved_receiver
.mclass
== anchor
.mclass
1506 resolved_receiver
= anchor
.arguments
[resolved_receiver
.rank
]
1507 if resolved_receiver
isa MNullableType then resolved_receiver
= resolved_receiver
.mtype
1509 assert resolved_receiver
isa MClassType # It is the only remaining type
1511 # Eh! The parameter is in the current class.
1512 # So we return the corresponding argument, no mater what!
1513 if resolved_receiver
.mclass
== self.mclass
then
1514 var res
= resolved_receiver
.arguments
[self.rank
]
1515 #print "{class_name}: {self}/{mtype}/{anchor} -> direct {res}"
1519 if resolved_receiver
.need_anchor
then
1520 assert anchor
!= null
1521 resolved_receiver
= resolved_receiver
.resolve_for
(anchor
, null, mmodule
, false)
1523 # Now, we can get the bound
1524 var verbatim_bound
= lookup_bound
(mmodule
, resolved_receiver
)
1525 # The bound is exactly as declared in the "type" property, so we must resolve it again
1526 var res
= verbatim_bound
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1528 #print "{class_name}: {self}/{mtype}/{anchor} -> indirect {res}"
1533 redef fun can_resolve_for
(mtype
, anchor
, mmodule
)
1535 if mtype
.need_anchor
then
1536 assert anchor
!= null
1537 mtype
= mtype
.anchor_to
(mmodule
, anchor
)
1539 return mtype
.collect_mclassdefs
(mmodule
).has
(mclass
.intro
)
1543 # A type that decorates another type.
1545 # The point of this class is to provide a common implementation of sevices that just forward to the original type.
1546 # Specific decorator are expected to redefine (or to extend) the default implementation as this suit them.
1547 abstract class MProxyType
1552 redef fun model
do return self.mtype
.model
1553 redef fun need_anchor
do return mtype
.need_anchor
1554 redef fun as_nullable
do return mtype
.as_nullable
1555 redef fun as_notnull
do return mtype
.as_notnull
1556 redef fun undecorate
do return mtype
.undecorate
1557 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1559 var res
= self.mtype
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1563 redef fun can_resolve_for
(mtype
, anchor
, mmodule
)
1565 return self.mtype
.can_resolve_for
(mtype
, anchor
, mmodule
)
1568 redef fun lookup_fixed
(mmodule
, resolved_receiver
)
1570 var t
= mtype
.lookup_fixed
(mmodule
, resolved_receiver
)
1574 redef fun depth
do return self.mtype
.depth
1576 redef fun length
do return self.mtype
.length
1578 redef fun collect_mclassdefs
(mmodule
)
1580 assert not self.need_anchor
1581 return self.mtype
.collect_mclassdefs
(mmodule
)
1584 redef fun collect_mclasses
(mmodule
)
1586 assert not self.need_anchor
1587 return self.mtype
.collect_mclasses
(mmodule
)
1590 redef fun collect_mtypes
(mmodule
)
1592 assert not self.need_anchor
1593 return self.mtype
.collect_mtypes
(mmodule
)
1597 # A type prefixed with "nullable"
1603 self.to_s
= "nullable {mtype}"
1606 redef var to_s
: String is noinit
1608 redef var full_name
is lazy
do return "nullable {mtype.full_name}"
1610 redef var c_name
is lazy
do return "nullable__{mtype.c_name}"
1612 redef fun as_nullable
do return self
1613 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1616 return res
.as_nullable
1619 # Efficiently returns `mtype.lookup_fixed(mmodule, resolved_receiver).as_nullable`
1620 redef fun lookup_fixed
(mmodule
, resolved_receiver
)
1623 if t
== mtype
then return self
1624 return t
.as_nullable
1628 # A non-null version of a formal type.
1630 # When a formal type in bounded to a nullable type, this is the type of the not null version of it.
1634 redef fun to_s
do return "not null {mtype}"
1635 redef var full_name
is lazy
do return "not null {mtype.full_name}"
1636 redef var c_name
is lazy
do return "notnull__{mtype.c_name}"
1638 redef fun as_notnull
do return self
1640 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1643 return res
.as_notnull
1646 # Efficiently returns `mtype.lookup_fixed(mmodule, resolved_receiver).as_notnull`
1647 redef fun lookup_fixed
(mmodule
, resolved_receiver
)
1650 if t
== mtype
then return self
1655 # The type of the only value null
1657 # The is only one null type per model, see `MModel::null_type`.
1660 redef var model
: Model
1661 redef fun to_s
do return "null"
1662 redef fun full_name
do return "null"
1663 redef fun c_name
do return "null"
1664 redef fun as_nullable
do return self
1667 redef fun as_notnull
do abort # sorry...
1668 redef fun need_anchor
do return false
1669 redef fun resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
) do return self
1670 redef fun can_resolve_for
(mtype
, anchor
, mmodule
) do return true
1672 redef fun collect_mclassdefs
(mmodule
) do return new HashSet[MClassDef]
1674 redef fun collect_mclasses
(mmodule
) do return new HashSet[MClass]
1676 redef fun collect_mtypes
(mmodule
) do return new HashSet[MClassType]
1679 # A signature of a method
1683 # The each parameter (in order)
1684 var mparameters
: Array[MParameter]
1686 # The return type (null for a procedure)
1687 var return_mtype
: nullable MType
1692 var t
= self.return_mtype
1693 if t
!= null then dmax
= t
.depth
1694 for p
in mparameters
do
1695 var d
= p
.mtype
.depth
1696 if d
> dmax
then dmax
= d
1704 var t
= self.return_mtype
1705 if t
!= null then res
+= t
.length
1706 for p
in mparameters
do
1707 res
+= p
.mtype
.length
1712 # REQUIRE: 1 <= mparameters.count p -> p.is_vararg
1715 var vararg_rank
= -1
1716 for i
in [0..mparameters
.length
[ do
1717 var parameter
= mparameters
[i
]
1718 if parameter
.is_vararg
then
1719 assert vararg_rank
== -1
1723 self.vararg_rank
= vararg_rank
1726 # The rank of the ellipsis (`...`) for vararg (starting from 0).
1727 # value is -1 if there is no vararg.
1728 # Example: for "(a: Int, b: Bool..., c: Char)" #-> vararg_rank=1
1729 var vararg_rank
: Int is noinit
1731 # The number or parameters
1732 fun arity
: Int do return mparameters
.length
1736 var b
= new FlatBuffer
1737 if not mparameters
.is_empty
then
1739 for i
in [0..mparameters
.length
[ do
1740 var mparameter
= mparameters
[i
]
1741 if i
> 0 then b
.append
(", ")
1742 b
.append
(mparameter
.name
)
1744 b
.append
(mparameter
.mtype
.to_s
)
1745 if mparameter
.is_vararg
then
1751 var ret
= self.return_mtype
1759 redef fun resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule, cleanup_virtual
: Bool): MSignature
1761 var params
= new Array[MParameter]
1762 for p
in self.mparameters
do
1763 params
.add
(p
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
))
1765 var ret
= self.return_mtype
1767 ret
= ret
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1769 var res
= new MSignature(params
, ret
)
1774 # A parameter in a signature
1778 # The name of the parameter
1779 redef var name
: String
1781 # The static type of the parameter
1784 # Is the parameter a vararg?
1790 return "{name}: {mtype}..."
1792 return "{name}: {mtype}"
1796 # Returns a new parameter with the `mtype` resolved.
1797 # See `MType::resolve_for` for details.
1798 fun resolve_for
(mtype
: MType, anchor
: nullable MClassType, mmodule
: MModule, cleanup_virtual
: Bool): MParameter
1800 if not self.mtype
.need_anchor
then return self
1801 var newtype
= self.mtype
.resolve_for
(mtype
, anchor
, mmodule
, cleanup_virtual
)
1802 var res
= new MParameter(self.name
, newtype
, self.is_vararg
)
1806 redef fun model
do return mtype
.model
1809 # A service (global property) that generalize method, attribute, etc.
1811 # `MProperty` are global to the model; it means that a `MProperty` is not bound
1812 # to a specific `MModule` nor a specific `MClass`.
1814 # A MProperty gather definitions (see `mpropdefs`) ; one for the introduction
1815 # and the other in subclasses and in refinements.
1817 # A `MProperty` is used to denotes services in polymorphic way (ie. independent
1818 # of any dynamic type).
1819 # For instance, a call site "x.foo" is associated to a `MProperty`.
1820 abstract class MProperty
1823 # The associated MPropDef subclass.
1824 # The two specialization hierarchy are symmetric.
1825 type MPROPDEF: MPropDef
1827 # The classdef that introduce the property
1828 # While a property is not bound to a specific module, or class,
1829 # the introducing mclassdef is used for naming and visibility
1830 var intro_mclassdef
: MClassDef
1832 # The (short) name of the property
1833 redef var name
: String
1835 # The canonical name of the property.
1837 # It is the short-`name` prefixed by the short-name of the class and the full-name of the module.
1838 # Example: "my_project::my_module::MyClass::my_method"
1839 redef var full_name
is lazy
do
1840 return "{intro_mclassdef.mmodule.namespace_for(visibility)}::{intro_mclassdef.mclass.name}::{name}"
1843 redef var c_name
is lazy
do
1844 # FIXME use `namespace_for`
1845 return "{intro_mclassdef.mmodule.c_name}__{intro_mclassdef.mclass.name.to_cmangle}__{name.to_cmangle}"
1848 # The visibility of the property
1849 var visibility
: MVisibility
1851 # Is the property usable as an initializer?
1852 var is_autoinit
= false is writable
1856 intro_mclassdef
.intro_mproperties
.add
(self)
1857 var model
= intro_mclassdef
.mmodule
.model
1858 model
.mproperties_by_name
.add_one
(name
, self)
1859 model
.mproperties
.add
(self)
1862 # All definitions of the property.
1863 # The first is the introduction,
1864 # The other are redefinitions (in refinements and in subclasses)
1865 var mpropdefs
= new Array[MPROPDEF]
1867 # The definition that introduces the property.
1869 # Warning: such a definition may not exist in the early life of the object.
1870 # In this case, the method will abort.
1871 var intro
: MPROPDEF is noinit
1873 redef fun model
do return intro
.model
1876 redef fun to_s
do return name
1878 # Return the most specific property definitions defined or inherited by a type.
1879 # The selection knows that refinement is stronger than specialization;
1880 # however, in case of conflict more than one property are returned.
1881 # If mtype does not know mproperty then an empty array is returned.
1883 # If you want the really most specific property, then look at `lookup_first_definition`
1885 # REQUIRE: `not mtype.need_anchor` to simplify the API (no `anchor` parameter)
1886 # ENSURE: `not mtype.has_mproperty(mmodule, self) == result.is_empty`
1887 fun lookup_definitions
(mmodule
: MModule, mtype
: MType): Array[MPROPDEF]
1889 assert not mtype
.need_anchor
1890 mtype
= mtype
.undecorate
1892 var cache
= self.lookup_definitions_cache
[mmodule
, mtype
]
1893 if cache
!= null then return cache
1895 #print "select prop {mproperty} for {mtype} in {self}"
1896 # First, select all candidates
1897 var candidates
= new Array[MPROPDEF]
1898 for mpropdef
in self.mpropdefs
do
1899 # If the definition is not imported by the module, then skip
1900 if not mmodule
.in_importation
<= mpropdef
.mclassdef
.mmodule
then continue
1901 # If the definition is not inherited by the type, then skip
1902 if not mtype
.is_subtype
(mmodule
, null, mpropdef
.mclassdef
.bound_mtype
) then continue
1904 candidates
.add
(mpropdef
)
1906 # Fast track for only one candidate
1907 if candidates
.length
<= 1 then
1908 self.lookup_definitions_cache
[mmodule
, mtype
] = candidates
1912 # Second, filter the most specific ones
1913 return select_most_specific
(mmodule
, candidates
)
1916 private var lookup_definitions_cache
= new HashMap2[MModule, MType, Array[MPROPDEF]]
1918 # Return the most specific property definitions inherited by a type.
1919 # The selection knows that refinement is stronger than specialization;
1920 # however, in case of conflict more than one property are returned.
1921 # If mtype does not know mproperty then an empty array is returned.
1923 # If you want the really most specific property, then look at `lookup_next_definition`
1925 # REQUIRE: `not mtype.need_anchor` to simplify the API (no `anchor` parameter)
1926 # ENSURE: `not mtype.has_mproperty(mmodule, self) implies result.is_empty`
1927 fun lookup_super_definitions
(mmodule
: MModule, mtype
: MType): Array[MPROPDEF]
1929 assert not mtype
.need_anchor
1930 mtype
= mtype
.undecorate
1932 # First, select all candidates
1933 var candidates
= new Array[MPROPDEF]
1934 for mpropdef
in self.mpropdefs
do
1935 # If the definition is not imported by the module, then skip
1936 if not mmodule
.in_importation
<= mpropdef
.mclassdef
.mmodule
then continue
1937 # If the definition is not inherited by the type, then skip
1938 if not mtype
.is_subtype
(mmodule
, null, mpropdef
.mclassdef
.bound_mtype
) then continue
1939 # If the definition is defined by the type, then skip (we want the super, so e skip the current)
1940 if mtype
== mpropdef
.mclassdef
.bound_mtype
and mmodule
== mpropdef
.mclassdef
.mmodule
then continue
1942 candidates
.add
(mpropdef
)
1944 # Fast track for only one candidate
1945 if candidates
.length
<= 1 then return candidates
1947 # Second, filter the most specific ones
1948 return select_most_specific
(mmodule
, candidates
)
1951 # Return an array containing olny the most specific property definitions
1952 # This is an helper function for `lookup_definitions` and `lookup_super_definitions`
1953 private fun select_most_specific
(mmodule
: MModule, candidates
: Array[MPROPDEF]): Array[MPROPDEF]
1955 var res
= new Array[MPROPDEF]
1956 for pd1
in candidates
do
1957 var cd1
= pd1
.mclassdef
1960 for pd2
in candidates
do
1961 if pd2
== pd1
then continue # do not compare with self!
1962 var cd2
= pd2
.mclassdef
1964 if c2
.mclass_type
== c1
.mclass_type
then
1965 if cd2
.mmodule
.in_importation
< cd1
.mmodule
then
1966 # cd2 refines cd1; therefore we skip pd1
1970 else if cd2
.bound_mtype
.is_subtype
(mmodule
, null, cd1
.bound_mtype
) and cd2
.bound_mtype
!= cd1
.bound_mtype
then
1971 # cd2 < cd1; therefore we skip pd1
1980 if res
.is_empty
then
1981 print
"All lost! {candidates.join(", ")}"
1982 # FIXME: should be abort!
1987 # Return the most specific definition in the linearization of `mtype`.
1989 # If you want to know the next properties in the linearization,
1990 # look at `MPropDef::lookup_next_definition`.
1992 # FIXME: the linearization is still unspecified
1994 # REQUIRE: `not mtype.need_anchor` to simplify the API (no `anchor` parameter)
1995 # REQUIRE: `mtype.has_mproperty(mmodule, self)`
1996 fun lookup_first_definition
(mmodule
: MModule, mtype
: MType): MPROPDEF
1998 return lookup_all_definitions
(mmodule
, mtype
).first
2001 # Return all definitions in a linearization order
2002 # Most specific first, most general last
2004 # REQUIRE: `not mtype.need_anchor` to simplify the API (no `anchor` parameter)
2005 # REQUIRE: `mtype.has_mproperty(mmodule, self)`
2006 fun lookup_all_definitions
(mmodule
: MModule, mtype
: MType): Array[MPROPDEF]
2008 mtype
= mtype
.undecorate
2010 var cache
= self.lookup_all_definitions_cache
[mmodule
, mtype
]
2011 if cache
!= null then return cache
2013 assert not mtype
.need_anchor
2014 assert mtype
.has_mproperty
(mmodule
, self)
2016 #print "select prop {mproperty} for {mtype} in {self}"
2017 # First, select all candidates
2018 var candidates
= new Array[MPROPDEF]
2019 for mpropdef
in self.mpropdefs
do
2020 # If the definition is not imported by the module, then skip
2021 if not mmodule
.in_importation
<= mpropdef
.mclassdef
.mmodule
then continue
2022 # If the definition is not inherited by the type, then skip
2023 if not mtype
.is_subtype
(mmodule
, null, mpropdef
.mclassdef
.bound_mtype
) then continue
2025 candidates
.add
(mpropdef
)
2027 # Fast track for only one candidate
2028 if candidates
.length
<= 1 then
2029 self.lookup_all_definitions_cache
[mmodule
, mtype
] = candidates
2033 mmodule
.linearize_mpropdefs
(candidates
)
2034 candidates
= candidates
.reversed
2035 self.lookup_all_definitions_cache
[mmodule
, mtype
] = candidates
2039 private var lookup_all_definitions_cache
= new HashMap2[MModule, MType, Array[MPROPDEF]]
2046 redef type MPROPDEF: MMethodDef
2048 # Is the property defined at the top_level of the module?
2049 # Currently such a property are stored in `Object`
2050 var is_toplevel
: Bool = false is writable
2052 # Is the property a constructor?
2053 # Warning, this property can be inherited by subclasses with or without being a constructor
2054 # therefore, you should use `is_init_for` the verify if the property is a legal constructor for a given class
2055 var is_init
: Bool = false is writable
2057 # The constructor is a (the) root init with empty signature but a set of initializers
2058 var is_root_init
: Bool = false is writable
2060 # Is the property a 'new' constructor?
2061 var is_new
: Bool = false is writable
2063 # Is the property a legal constructor for a given class?
2064 # As usual, visibility is not considered.
2065 # FIXME not implemented
2066 fun is_init_for
(mclass
: MClass): Bool
2072 # A global attribute
2076 redef type MPROPDEF: MAttributeDef
2080 # A global virtual type
2081 class MVirtualTypeProp
2084 redef type MPROPDEF: MVirtualTypeDef
2086 # The formal type associated to the virtual type property
2087 var mvirtualtype
= new MVirtualType(self)
2090 # A definition of a property (local property)
2092 # Unlike `MProperty`, a `MPropDef` is a local definition that belong to a
2093 # specific class definition (which belong to a specific module)
2094 abstract class MPropDef
2097 # The associated `MProperty` subclass.
2098 # the two specialization hierarchy are symmetric
2099 type MPROPERTY: MProperty
2102 type MPROPDEF: MPropDef
2104 # The class definition where the property definition is
2105 var mclassdef
: MClassDef
2107 # The associated global property
2108 var mproperty
: MPROPERTY
2110 # The origin of the definition
2111 var location
: Location
2115 mclassdef
.mpropdefs
.add
(self)
2116 mproperty
.mpropdefs
.add
(self)
2117 if mproperty
.intro_mclassdef
== mclassdef
then
2118 assert not isset mproperty
._intro
2119 mproperty
.intro
= self
2121 self.to_s
= "{mclassdef}#{mproperty}"
2124 # Actually the name of the `mproperty`
2125 redef fun name
do return mproperty
.name
2127 # The full-name of mpropdefs combine the information about the `classdef` and the `mproperty`.
2129 # Therefore the combination of identifiers is awful,
2130 # the worst case being
2132 # * a property "p::m::A::x"
2133 # * redefined in a refinement of a class "q::n::B"
2134 # * in a module "r::o"
2135 # * so "r::o#q::n::B#p::m::A::x"
2137 # Fortunately, the full-name is simplified when entities are repeated.
2138 # For the previous case, the simplest form is "p#A#x".
2139 redef var full_name
is lazy
do
2140 var res
= new FlatBuffer
2142 # The first part is the mclassdef. Worst case is "r::o#q::n::B"
2143 res
.append mclassdef
.full_name
2147 if mclassdef
.mclass
== mproperty
.intro_mclassdef
.mclass
then
2148 # intro are unambiguous in a class
2151 # Just try to simplify each part
2152 if mclassdef
.mmodule
.mproject
!= mproperty
.intro_mclassdef
.mmodule
.mproject
then
2153 # precise "p::m" only if "p" != "r"
2154 res
.append mproperty
.intro_mclassdef
.mmodule
.full_name
2156 else if mproperty
.visibility
<= private_visibility
then
2157 # Same project ("p"=="q"), but private visibility,
2158 # does the module part ("::m") need to be displayed
2159 if mclassdef
.mmodule
.namespace_for
(mclassdef
.mclass
.visibility
) != mproperty
.intro_mclassdef
.mmodule
.mproject
then
2161 res
.append mproperty
.intro_mclassdef
.mmodule
.name
2165 if mclassdef
.mclass
!= mproperty
.intro_mclassdef
.mclass
then
2166 # precise "B" only if not the same class than "A"
2167 res
.append mproperty
.intro_mclassdef
.name
2170 # Always use the property name "x"
2171 res
.append mproperty
.name
2176 redef var c_name
is lazy
do
2177 var res
= new FlatBuffer
2178 res
.append mclassdef
.c_name
2180 if mclassdef
.mclass
== mproperty
.intro_mclassdef
.mclass
then
2181 res
.append name
.to_cmangle
2183 if mclassdef
.mmodule
!= mproperty
.intro_mclassdef
.mmodule
then
2184 res
.append mproperty
.intro_mclassdef
.mmodule
.c_name
2187 if mclassdef
.mclass
!= mproperty
.intro_mclassdef
.mclass
then
2188 res
.append mproperty
.intro_mclassdef
.name
.to_cmangle
2191 res
.append mproperty
.name
.to_cmangle
2196 redef fun model
do return mclassdef
.model
2198 # Internal name combining the module, the class and the property
2199 # Example: "mymodule#MyClass#mymethod"
2200 redef var to_s
: String is noinit
2202 # Is self the definition that introduce the property?
2203 fun is_intro
: Bool do return mproperty
.intro
== self
2205 # Return the next definition in linearization of `mtype`.
2207 # This method is used to determine what method is called by a super.
2209 # REQUIRE: `not mtype.need_anchor`
2210 fun lookup_next_definition
(mmodule
: MModule, mtype
: MType): MPROPDEF
2212 assert not mtype
.need_anchor
2214 var mpropdefs
= self.mproperty
.lookup_all_definitions
(mmodule
, mtype
)
2215 var i
= mpropdefs
.iterator
2216 while i
.is_ok
and i
.item
!= self do i
.next
2217 assert has_property
: i
.is_ok
2219 assert has_next_property
: i
.is_ok
2224 # A local definition of a method
2228 redef type MPROPERTY: MMethod
2229 redef type MPROPDEF: MMethodDef
2231 # The signature attached to the property definition
2232 var msignature
: nullable MSignature = null is writable
2234 # The signature attached to the `new` call on a root-init
2235 # This is a concatenation of the signatures of the initializers
2237 # REQUIRE `mproperty.is_root_init == (new_msignature != null)`
2238 var new_msignature
: nullable MSignature = null is writable
2240 # List of initialisers to call in root-inits
2242 # They could be setters or attributes
2244 # REQUIRE `mproperty.is_root_init == (new_msignature != null)`
2245 var initializers
= new Array[MProperty]
2247 # Is the method definition abstract?
2248 var is_abstract
: Bool = false is writable
2250 # Is the method definition intern?
2251 var is_intern
= false is writable
2253 # Is the method definition extern?
2254 var is_extern
= false is writable
2256 # An optional constant value returned in functions.
2258 # Only some specific primitife value are accepted by engines.
2259 # Is used when there is no better implementation available.
2261 # Currently used only for the implementation of the `--define`
2262 # command-line option.
2263 # SEE: module `mixin`.
2264 var constant_value
: nullable Object = null is writable
2267 # A local definition of an attribute
2271 redef type MPROPERTY: MAttribute
2272 redef type MPROPDEF: MAttributeDef
2274 # The static type of the attribute
2275 var static_mtype
: nullable MType = null is writable
2278 # A local definition of a virtual type
2279 class MVirtualTypeDef
2282 redef type MPROPERTY: MVirtualTypeProp
2283 redef type MPROPDEF: MVirtualTypeDef
2285 # The bound of the virtual type
2286 var bound
: nullable MType = null is writable
2288 # Is the bound fixed?
2289 var is_fixed
= false is writable
2296 # * `interface_kind`
2300 # Note this class is basically an enum.
2301 # FIXME: use a real enum once user-defined enums are available
2303 redef var to_s
: String
2305 # Is a constructor required?
2308 # TODO: private init because enumeration.
2310 # Can a class of kind `self` specializes a class of kine `other`?
2311 fun can_specialize
(other
: MClassKind): Bool
2313 if other
== interface_kind
then return true # everybody can specialize interfaces
2314 if self == interface_kind
or self == enum_kind
then
2315 # no other case for interfaces
2317 else if self == extern_kind
then
2318 # only compatible with themselves
2319 return self == other
2320 else if other
== enum_kind
or other
== extern_kind
then
2321 # abstract_kind and concrete_kind are incompatible
2324 # remain only abstract_kind and concrete_kind
2329 # The class kind `abstract`
2330 fun abstract_kind
: MClassKind do return once
new MClassKind("abstract class", true)
2331 # The class kind `concrete`
2332 fun concrete_kind
: MClassKind do return once
new MClassKind("class", true)
2333 # The class kind `interface`
2334 fun interface_kind
: MClassKind do return once
new MClassKind("interface", false)
2335 # The class kind `enum`
2336 fun enum_kind
: MClassKind do return once
new MClassKind("enum", false)
2337 # The class kind `extern`
2338 fun extern_kind
: MClassKind do return once
new MClassKind("extern class", false)