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 # Intraprocedural resolution of static types and OO-services
18 # By OO-services we mean message sending, attribute access, instantiation, etc.
25 redef class ToolContext
26 var typing_phase
: Phase = new TypingPhase(self, [flow_phase
, modelize_property_phase
, local_var_init_phase
])
29 private class TypingPhase
31 redef fun process_npropdef
(npropdef
) do npropdef
.do_typing
(toolcontext
.modelbuilder
)
34 private class TypeVisitor
35 var modelbuilder
: ModelBuilder
37 # The module of the analysis
38 # Used to correctly query the model
41 # The static type of the receiver
42 # Mainly used for type tests and type resolutions
43 var anchor
: nullable MClassType = null
45 # The analyzed mclassdef
46 var mclassdef
: nullable MClassDef = null
48 # The analyzed property
49 var mpropdef
: nullable MPropDef
51 var selfvariable
= new Variable("self")
53 # Is `self` use restricted?
54 # * no explicit `self`
55 # * method called on the implicit self must be top-level
56 # Currently only used for `new` factory since there is no valid receiver inside
57 var is_toplevel_context
= false
61 var mpropdef
= self.mpropdef
63 if mpropdef
!= null then
64 self.mpropdef
= mpropdef
65 var mclassdef
= mpropdef
.mclassdef
66 self.mclassdef
= mclassdef
67 self.anchor
= mclassdef
.bound_mtype
69 var mclass
= mclassdef
.mclass
71 var selfvariable
= new Variable("self")
72 self.selfvariable
= selfvariable
73 selfvariable
.declared_type
= mclass
.mclass_type
75 var mprop
= mpropdef
.mproperty
76 if mprop
isa MMethod and mprop
.is_new
then
77 is_toplevel_context
= true
82 fun anchor_to
(mtype
: MType): MType
85 if anchor
== null then
86 assert not mtype
.need_anchor
89 return mtype
.anchor_to
(mmodule
, anchor
)
92 fun is_subtype
(sub
, sup
: MType): Bool
94 return sub
.is_subtype
(mmodule
, anchor
, sup
)
97 fun resolve_for
(mtype
, subtype
: MType, for_self
: Bool): MType
99 #print "resolve_for {mtype} sub={subtype} forself={for_self} mmodule={mmodule} anchor={anchor}"
100 var res
= mtype
.resolve_for
(subtype
, anchor
, mmodule
, not for_self
)
104 # Check that `sub` is a subtype of `sup`.
105 # If `sub` is not a valid suptype, then display an error on `node` an return null.
106 # If `sub` is a safe subtype of `sup` then return `sub`.
107 # If `sub` is an unsafe subtype (ie an implicit cast is required), then return `sup`.
109 # The point of the return type is to determinate the usable type on an expression when `autocast` is true:
110 # If the suptype is safe, then the return type is the one on the expression typed by `sub`.
111 # Is the subtype is unsafe, then the return type is the one of an implicit cast on `sup`.
112 fun check_subtype
(node
: ANode, sub
, sup
: MType, autocast
: Bool): nullable MType
114 if self.is_subtype
(sub
, sup
) then return sub
115 if autocast
and self.is_subtype
(sub
, self.anchor_to
(sup
)) then
116 # FIXME workaround to the current unsafe typing policy. To remove once fixed virtual types exists.
117 #node.debug("Unsafe typing: expected {sup}, got {sub}")
120 if sub
.need_anchor
then
121 var u
= anchor_to
(sub
)
122 self.modelbuilder
.error
(node
, "Type Error: expected `{sup}`, got `{sub}: {u}`.")
124 self.modelbuilder
.error
(node
, "Type Error: expected `{sup}`, got `{sub}`.")
129 # Visit an expression and do not care about the return value
130 fun visit_stmt
(nexpr
: nullable AExpr)
132 if nexpr
== null then return
133 nexpr
.accept_typing
(self)
136 # Visit an expression and expects that it is not a statement
137 # Return the type of the expression
138 # Display an error and return null if:
139 # * the type cannot be determined or
140 # * `nexpr` is a statement
141 fun visit_expr
(nexpr
: AExpr): nullable MType
143 nexpr
.accept_typing
(self)
144 var mtype
= nexpr
.mtype
145 if mtype
!= null then return mtype
146 if not nexpr
.is_typed
then
147 if not self.modelbuilder
.toolcontext
.error_count
> 0 then # check that there is really an error
148 if self.modelbuilder
.toolcontext
.verbose_level
> 1 then
149 nexpr
.debug
("No return type but no error.")
152 return null # forward error
154 self.error
(nexpr
, "Error: expected an expression.")
158 # Visit an expression and expect its static type is a least a `sup`
159 # Return the type of the expression or null if
160 # * the type cannot be determined or
161 # * `nexpr` is a statement or
162 # * `nexpr` is not a `sup`
163 fun visit_expr_subtype
(nexpr
: AExpr, sup
: nullable MType): nullable MType
165 var sub
= visit_expr
(nexpr
)
166 if sub
== null then return null # Forward error
168 if sup
== null then return null # Forward error
170 var res
= check_subtype
(nexpr
, sub
, sup
, true)
172 nexpr
.implicit_cast_to
= res
177 # Visit an expression and expect its static type is a `Bool`
178 # Return the type of the expression or null if
179 # * the type cannot be determined or
180 # * `nexpr` is a statement or
181 # * `nexpr` is not a `Bool`
182 fun visit_expr_bool
(nexpr
: AExpr): nullable MType
184 return self.visit_expr_subtype
(nexpr
, self.type_bool
(nexpr
))
188 fun check_expr_cast
(node
: ANode, nexpr
: AExpr, ntype
: AType): nullable MType
190 var sub
= nexpr
.mtype
191 if sub
== null then return null # Forward error
193 var sup
= ntype
.mtype
194 if sup
== null then return null # Forward error
197 self.modelbuilder
.warning
(node
, "useless-type-test", "Warning: expression is already a `{sup}`.")
198 else if self.is_subtype
(sub
, sup
) then
199 self.modelbuilder
.warning
(node
, "useless-type-test", "Warning: expression is already a `{sup}` since it is a `{sub}`.")
204 # Can `mtype` be null (up to the current knowledge)?
205 fun can_be_null
(mtype
: MType): Bool
207 if mtype
isa MNullableType or mtype
isa MNullType then return true
208 if mtype
isa MFormalType then
209 var x
= anchor_to
(mtype
)
210 if x
isa MNullableType or x
isa MNullType then return true
215 # Check that `mtype` can be null (up to the current knowledge).
217 # If not then display a `useless-null-test` warning on node and return false.
219 fun check_can_be_null
(anode
: ANode, mtype
: MType): Bool
221 if mtype
isa MNullType then
222 modelbuilder
.warning
(anode
, "useless-null-test", "Warning: expression is always `null`.")
225 if can_be_null
(mtype
) then return true
227 if mtype
isa MFormalType then
228 var res
= anchor_to
(mtype
)
229 modelbuilder
.warning
(anode
, "useless-null-test", "Warning: expression is not null, since it is a `{mtype}: {res}`.")
231 modelbuilder
.warning
(anode
, "useless-null-test", "Warning: expression is not null, since it is a `{mtype}`.")
236 # Special verification on != and == for null
238 fun null_test
(anode
: ABinopExpr)
240 var mtype
= anode
.n_expr
.mtype
241 var mtype2
= anode
.n_expr2
.mtype
243 if mtype
== null or mtype2
== null then return
245 if not mtype2
isa MNullType then return
247 # Check of useless null
248 if not can_be_null
(mtype
) then return
250 if mtype
isa MNullType then
251 # Because of type adaptation, we cannot just stop here
252 # so return use `null` as a bottom type that will be merged easily (cf) `merge_types`
255 mtype
= mtype
.as_notnull
258 # Check for type adaptation
259 var variable
= anode
.n_expr
.its_variable
260 if variable
== null then return
262 # One is null (mtype2 see above) the other is not null
263 if anode
isa AEqExpr then
264 anode
.after_flow_context
.when_true
.set_var
(self, variable
, mtype2
)
265 anode
.after_flow_context
.when_false
.set_var
(self, variable
, mtype
)
266 else if anode
isa ANeExpr then
267 anode
.after_flow_context
.when_false
.set_var
(self, variable
, mtype2
)
268 anode
.after_flow_context
.when_true
.set_var
(self, variable
, mtype
)
274 fun try_get_mproperty_by_name2
(anode
: ANode, mtype
: MType, name
: String): nullable MProperty
276 return self.modelbuilder
.try_get_mproperty_by_name2
(anode
, mmodule
, mtype
, name
)
279 fun resolve_mtype
(node
: AType): nullable MType
281 return self.modelbuilder
.resolve_mtype
(mmodule
, mclassdef
, node
)
284 fun try_get_mclass
(node
: ANode, name
: String): nullable MClass
286 var mclass
= modelbuilder
.try_get_mclass_by_name
(node
, mmodule
, name
)
290 fun get_mclass
(node
: ANode, name
: String): nullable MClass
292 var mclass
= modelbuilder
.get_mclass_by_name
(node
, mmodule
, name
)
296 fun type_bool
(node
: ANode): nullable MType
298 var mclass
= self.get_mclass
(node
, "Bool")
299 if mclass
== null then return null
300 return mclass
.mclass_type
303 fun get_method
(node
: ANode, recvtype
: MType, name
: String, recv_is_self
: Bool): nullable CallSite
305 var unsafe_type
= self.anchor_to
(recvtype
)
307 #debug("recv: {recvtype} (aka {unsafe_type})")
308 if recvtype
isa MNullType then
309 var objclass
= get_mclass
(node
, "Object")
310 if objclass
== null then return null # Forward error
311 unsafe_type
= objclass
.mclass_type
314 var mproperty
= self.try_get_mproperty_by_name2
(node
, unsafe_type
, name
)
315 if name
== "new" and mproperty
== null then
317 mproperty
= self.try_get_mproperty_by_name2
(node
, unsafe_type
, name
)
320 if mproperty
== null then
322 self.modelbuilder
.error
(node
, "Error: method or variable `{name}` unknown in `{recvtype}`.")
323 else if recvtype
.need_anchor
then
324 self.modelbuilder
.error
(node
, "Error: method `{name}` does not exists in `{recvtype}: {unsafe_type}`.")
326 self.modelbuilder
.error
(node
, "Error: method `{name}` does not exists in `{recvtype}`.")
331 assert mproperty
isa MMethod
333 # `null` only accepts some methods of object.
334 if recvtype
isa MNullType and not mproperty
.is_null_safe
then
335 self.error
(node
, "Error: method `{name}` called on `null`.")
337 else if unsafe_type
isa MNullableType and not mproperty
.is_null_safe
then
338 modelbuilder
.advice
(node
, "call-on-nullable", "Warning: method call on a nullable receiver `{recvtype}`.")
341 if is_toplevel_context
and recv_is_self
and not mproperty
.is_toplevel
then
342 error
(node
, "Error: `{name}` is not a top-level method, thus need a receiver.")
344 if not recv_is_self
and mproperty
.is_toplevel
then
345 error
(node
, "Error: cannot call `{name}`, a top-level method, with a receiver.")
348 if mproperty
.visibility
== protected_visibility
and not recv_is_self
and self.mmodule
.visibility_for
(mproperty
.intro_mclassdef
.mmodule
) < intrude_visibility
and not modelbuilder
.toolcontext
.opt_ignore_visibility
.value
then
349 self.modelbuilder
.error
(node
, "Error: method `{name}` is protected and can only accessed by `self`.")
353 var info
= mproperty
.deprecation
354 if info
!= null and self.mpropdef
.mproperty
.deprecation
== null then
357 self.modelbuilder
.warning
(node
, "deprecated-method", "Deprecation Warning: method `{name}` is deprecated: {mdoc.content.first}")
359 self.modelbuilder
.warning
(node
, "deprecated-method", "Deprecation Warning: method `{name}` is deprecated.")
363 var propdefs
= mproperty
.lookup_definitions
(self.mmodule
, unsafe_type
)
365 if propdefs
.length
== 0 then
366 self.modelbuilder
.error
(node
, "Type Error: no definition found for property `{name}` in `{unsafe_type}`.")
368 else if propdefs
.length
== 1 then
369 mpropdef
= propdefs
.first
371 self.modelbuilder
.warning
(node
, "property-conflict", "Warning: conflicting property definitions for property `{name}` in `{unsafe_type}`: {propdefs.join(" ")}")
372 mpropdef
= mproperty
.intro
376 var msignature
= mpropdef
.new_msignature
or else mpropdef
.msignature
377 if msignature
== null then return null # skip error
378 msignature
= resolve_for
(msignature
, recvtype
, recv_is_self
).as(MSignature)
380 var erasure_cast
= false
381 var rettype
= mpropdef
.msignature
.return_mtype
382 if not recv_is_self
and rettype
!= null then
383 rettype
= rettype
.undecorate
384 if rettype
isa MParameterType then
385 var erased_rettype
= msignature
.return_mtype
386 assert erased_rettype
!= null
387 #node.debug("Erasure cast: Really a {rettype} but unsafely a {erased_rettype}")
392 var callsite
= new CallSite(node
, recvtype
, mmodule
, anchor
, recv_is_self
, mproperty
, mpropdef
, msignature
, erasure_cast
)
396 fun try_get_method
(node
: ANode, recvtype
: MType, name
: String, recv_is_self
: Bool): nullable CallSite
398 var unsafe_type
= self.anchor_to
(recvtype
)
399 var mproperty
= self.try_get_mproperty_by_name2
(node
, unsafe_type
, name
)
400 if mproperty
== null then return null
401 return get_method
(node
, recvtype
, name
, recv_is_self
)
405 # Visit the expressions of args and check their conformity with the corresponding type in signature
406 # The point of this method is to handle varargs correctly
407 # Note: The signature must be correctly adapted
408 fun check_signature
(node
: ANode, args
: Array[AExpr], mproperty
: MProperty, msignature
: MSignature): nullable SignatureMap
410 var vararg_rank
= msignature
.vararg_rank
411 if vararg_rank
>= 0 then
412 if args
.length
< msignature
.arity
then
413 modelbuilder
.error
(node
, "Error: expected at least {msignature.arity} argument(s) for `{mproperty}{msignature}`; got {args.length}. See introduction at `{mproperty.full_name}`.")
416 else if args
.length
!= msignature
.arity
then
418 if args
.length
> msignature
.arity
then
419 modelbuilder
.error
(node
, "Error: expected {msignature.arity} argument(s) for `{mproperty}{msignature}`; got {args.length}. See introduction at `{mproperty.full_name}`.")
422 # Other cases are managed later
426 #debug("CALL {unsafe_type}.{msignature}")
428 # Associate each parameter to a position in the arguments
429 var map
= new SignatureMap
431 # Special case for the isolated last argument
432 # TODO: reify this method characteristics (where? the param, the signature, the method?)
433 var last_is_padded
= mproperty
.name
.chars
.last
== '='
434 var nbargs
= args
.length
435 if last_is_padded
then
437 assert not args
.last
isa ANamedargExpr
438 map
.map
[msignature
.arity
- 1] = args
.length
- 1
439 self.visit_expr_subtype
(args
.last
, msignature
.mparameters
.last
.mtype
)
442 # First, handle named arguments
443 for i
in [0..args
.length
[ do
445 if not e
isa ANamedargExpr then continue
446 var name
= e
.n_id
.text
447 var param
= msignature
.mparameter_by_name
(name
)
448 if param
== null then
449 modelbuilder
.error
(e
.n_id
, "Error: no parameter `{name}` for `{mproperty}{msignature}`.")
452 var idx
= msignature
.mparameters
.index_of
(param
)
453 var prev
= map
.map
.get_or_null
(idx
)
455 modelbuilder
.error
(e
, "Error: parameter `{name}` already associated with argument #{prev} for `{mproperty}{msignature}`.")
459 e
.mtype
= self.visit_expr_subtype
(e
.n_expr
, param
.mtype
)
462 # Number of minimum mandatory remaining parameters
465 # Second, associate remaining parameters
466 var vararg_decl
= args
.length
- msignature
.arity
468 for i
in [0..msignature
.arity
[ do
469 # Skip parameters associated by name
470 if map
.map
.has_key
(i
) then continue
472 var param
= msignature
.mparameters
[i
]
474 # Search the next free argument: skip named arguments since they are already associated
475 while j
< nbargs
and args
[j
] isa ANamedargExpr do j
+= 1
477 if not param
.mtype
isa MNullableType then
487 if i
== vararg_rank
then
489 continue # skip the vararg
492 var paramtype
= param
.mtype
493 self.visit_expr_subtype
(arg
, paramtype
)
496 if min_arity
> 0 then
497 if last_is_padded
then min_arity
+= 1
498 if min_arity
< msignature
.arity
then
499 modelbuilder
.error
(node
, "Error: expected at least {min_arity} argument(s) for `{mproperty}{msignature}`; got {args.length}. See introduction at `{mproperty.full_name}`.")
501 modelbuilder
.error
(node
, "Error: expected {min_arity} argument(s) for `{mproperty}{msignature}`; got {args.length}. See introduction at `{mproperty.full_name}`.")
506 # Third, check varargs
507 if vararg_rank
>= 0 then
508 var paramtype
= msignature
.mparameters
[vararg_rank
].mtype
509 var first
= args
[vararg_rank
]
510 if vararg_decl
== 0 then
511 var mclass
= get_mclass
(node
, "Array")
512 if mclass
== null then return null # Forward error
513 var array_mtype
= mclass
.get_mtype
([paramtype
])
514 if first
isa AVarargExpr then
515 self.visit_expr_subtype
(first
.n_expr
, array_mtype
)
516 first
.mtype
= first
.n_expr
.mtype
518 # only one vararg, maybe `...` was forgot, so be gentle!
519 var t
= visit_expr
(first
)
520 if t
== null then return null # Forward error
521 if not is_subtype
(t
, paramtype
) and is_subtype
(t
, array_mtype
) then
522 # Not acceptable but could be a `...`
523 error
(first
, "Type Error: expected `{paramtype}`, got `{t}`. Is an ellipsis `...` missing on the argument?")
526 # Standard valid vararg, finish the job
528 self.visit_expr_subtype
(first
, paramtype
)
531 map
.vararg_decl
= vararg_decl
+ 1
532 for i
in [vararg_rank
..vararg_rank
+vararg_decl
] do
533 self.visit_expr_subtype
(args
[i
], paramtype
)
541 fun error
(node
: ANode, message
: String)
543 self.modelbuilder
.error
(node
, message
)
546 fun get_variable
(node
: AExpr, variable
: Variable): nullable MType
548 if not variable
.is_adapted
then return variable
.declared_type
550 var flow
= node
.after_flow_context
551 if flow
== null then return null # skip error
553 if flow
.vars
.has_key
(variable
) then
554 return flow
.vars
[variable
]
556 #node.debug("*** START Collected for {variable}")
557 var mtypes
= flow
.collect_types
(variable
)
558 #node.debug("**** END Collected for {variable}")
559 if mtypes
.length
== 0 then
560 return variable
.declared_type
561 else if mtypes
.length
== 1 then
564 var res
= merge_types
(node
,mtypes
)
565 if res
== null then res
= variable
.declared_type
571 # Some variables where type-adapted during the visit
574 # Some loops had been visited during the visit
577 fun set_variable
(node
: AExpr, variable
: Variable, mtype
: nullable MType)
579 var flow
= node
.after_flow_context
582 flow
.set_var
(self, variable
, mtype
)
585 fun merge_types
(node
: ANode, col
: Array[nullable MType]): nullable MType
587 if col
.length
== 1 then return col
.first
589 if t1
== null then continue # return null
592 if t2
== null then continue # return null
593 if can_be_null
(t2
) and not can_be_null
(t1
) then
596 if not is_subtype
(t2
, t1
) then found
= false
599 #print "merge {col.join(" ")} -> {t1}"
603 #self.modelbuilder.warning(node, "Type Error: {col.length} conflicting types: <{col.join(", ")}>")
608 # Mapping between parameters and arguments in a call.
610 # Parameters and arguments are not stored in the class but referenced by their position (starting from 0)
612 # The point of this class is to help engine and other things to map arguments in the AST to parameters of the model.
614 # Associate a parameter to an argument
615 var map
= new ArrayMap[Int, Int]
617 # The length of the vararg sequence
618 # 0 if no vararg or if reverse vararg (cf `AVarargExpr`)
619 var vararg_decl
: Int = 0
622 # A specific method call site with its associated informations.
624 # The associated node for location
627 # The static type of the receiver (possibly unresolved)
630 # The module where the callsite is present
633 # The anchor to use with `recv` or `msignature`
634 var anchor
: nullable MClassType
636 # Is the receiver self?
637 # If "for_self", virtual types of the signature are kept
638 # If "not_for_self", virtual type are erased
639 var recv_is_self
: Bool
641 # The designated method
642 var mproperty
: MMethod
644 # The statically designated method definition
645 # The most specif one, it is.
646 var mpropdef
: MMethodDef
648 # The resolved signature for the receiver
649 var msignature
: MSignature
651 # Is a implicit cast required on erasure typing policy?
652 var erasure_cast
: Bool
654 # The mapping used on the call to associate arguments to parameters
655 # If null then no specific association is required.
656 var signaturemap
: nullable SignatureMap = null
658 private fun check_signature
(v
: TypeVisitor, args
: Array[AExpr]): Bool
660 var map
= v
.check_signature
(self.node
, args
, self.mproperty
, self.msignature
)
667 # The declared type of the variable
668 var declared_type
: nullable MType is writable
670 # Was the variable type-adapted?
671 # This is used to speedup type retrieval while it remains `false`
672 private var is_adapted
= false
675 redef class FlowContext
676 # Store changes of types because of type evolution
677 private var vars
= new HashMap[Variable, nullable MType]
679 # Adapt the variable to a static type
680 # Warning1: do not modify vars directly.
681 # Warning2: sub-flow may have cached a unadapted variable
682 private fun set_var
(v
: TypeVisitor, variable
: Variable, mtype
: nullable MType)
684 if variable
.declared_type
== mtype
and not variable
.is_adapted
then return
685 if vars
.has_key
(variable
) and vars
[variable
] == mtype
then return
686 self.vars
[variable
] = mtype
688 variable
.is_adapted
= true
689 #node.debug "set {variable} to {mtype or else "X"}"
692 # Look in the flow and previous flow and collect all first reachable type adaptation of a local variable
693 private fun collect_types
(variable
: Variable): Array[nullable MType]
695 #node.debug "flow for {variable}"
696 var res
= new Array[nullable MType]
699 var seen
= new HashSet[FlowContext]
700 while not todo
.is_empty
do
702 if f
.is_unreachable
then continue
703 if seen
.has
(f
) then continue
706 if f
.vars
.has_key
(variable
) then
707 # Found something. Collect it and do not process further on this path
708 res
.add f
.vars
[variable
]
709 #f.node.debug "process {variable}: got {f.vars[variable] or else "X"}"
711 todo
.add_all f
.previous
713 if f
.previous
.is_empty
then
714 # Root flowcontext mean a parameter or something related
715 res
.add variable
.declared_type
716 #f.node.debug "root process {variable}: got {variable.declared_type or else "X"}"
720 #self.node.debug "##### end flow for {variable}: {res.join(" ")}"
726 # The entry point of the whole typing analysis
727 fun do_typing
(modelbuilder
: ModelBuilder)
731 # The variable associated to the receiver (if any)
732 var selfvariable
: nullable Variable
735 redef class AMethPropdef
736 redef fun do_typing
(modelbuilder
: ModelBuilder)
738 var mpropdef
= self.mpropdef
739 if mpropdef
== null then return # skip error
741 var v
= new TypeVisitor(modelbuilder
, mpropdef
.mclassdef
.mmodule
, mpropdef
)
742 self.selfvariable
= v
.selfvariable
744 var mmethoddef
= self.mpropdef
.as(not null)
745 var msignature
= mmethoddef
.msignature
746 if msignature
== null then return # skip error
747 for i
in [0..msignature
.arity
[ do
748 var mtype
= msignature
.mparameters
[i
].mtype
749 if msignature
.vararg_rank
== i
then
750 var arrayclass
= v
.get_mclass
(self.n_signature
.n_params
[i
], "Array")
751 if arrayclass
== null then return # Skip error
752 mtype
= arrayclass
.get_mtype
([mtype
])
754 var variable
= self.n_signature
.n_params
[i
].variable
755 assert variable
!= null
756 variable
.declared_type
= mtype
759 var nblock
= self.n_block
760 if nblock
== null then return
765 if not v
.has_loop
or not v
.dirty
then break
768 var post_visitor
= new PostTypingVisitor(v
)
769 post_visitor
.enter_visit
(self)
771 if not nblock
.after_flow_context
.is_unreachable
and msignature
.return_mtype
!= null then
772 # We reach the end of the function without having a return, it is bad
773 v
.error
(self, "Error: reached end of function; expected `return` with a value.")
778 private class PostTypingVisitor
780 var type_visitor
: TypeVisitor
781 redef fun visit
(n
) do
783 n
.accept_post_typing
(type_visitor
)
784 if n
isa AExpr and n
.mtype
== null and not n
.is_typed
then
791 private fun accept_post_typing
(v
: TypeVisitor) do end
794 redef class AAttrPropdef
795 redef fun do_typing
(modelbuilder
: ModelBuilder)
797 if not has_value
then return
799 var mpropdef
= self.mreadpropdef
800 if mpropdef
== null or mpropdef
.msignature
== null then return # skip error
802 var v
= new TypeVisitor(modelbuilder
, mpropdef
.mclassdef
.mmodule
, mpropdef
)
803 self.selfvariable
= v
.selfvariable
805 var nexpr
= self.n_expr
806 if nexpr
!= null then
807 var mtype
= self.mtype
808 v
.visit_expr_subtype
(nexpr
, mtype
)
810 var nblock
= self.n_block
811 if nblock
!= null then
813 if not nblock
.after_flow_context
.is_unreachable
then
814 # We reach the end of the init without having a return, it is bad
815 v
.error
(self, "Error: reached end of block; expected `return`.")
824 # The static type of the expression.
825 # null if self is a statement or in case of error
826 var mtype
: nullable MType = null
828 # Is the statement correctly typed?
829 # Used to distinguish errors and statements when `mtype == null`
830 var is_typed
: Bool = false
832 # If required, the following implicit cast `.as(XXX)`
833 # Such a cast may by required after evaluating the expression when
834 # a unsafe operation is detected (silently accepted by the Nit language).
835 # The attribute is computed by `check_subtype`
836 var implicit_cast_to
: nullable MType = null
838 # Return the variable read (if any)
839 # Used to perform adaptive typing
840 fun its_variable
: nullable Variable do return null
842 private fun accept_typing
(v
: TypeVisitor)
844 v
.error
(self, "no implemented accept_typing for {self.class_name}")
847 # Is non-null if `self` is a leaf of a comprehension array construction.
848 # In this case, the enclosing literal array node is designated.
849 # The result of the evaluation of `self` must be
850 # stored inside the designated array (there is an implicit `push`)
851 var comprehension
: nullable AArrayExpr = null
854 redef class ABlockExpr
855 redef fun accept_typing
(v
)
857 for e
in self.n_expr
do v
.visit_stmt
(e
)
861 # The type of a blockexpr is the one of the last expression (or null if empty)
864 if self.n_expr
.is_empty
then return null
865 return self.n_expr
.last
.mtype
869 redef class AVardeclExpr
870 redef fun accept_typing
(v
)
872 var variable
= self.variable
873 if variable
== null then return # Skip error
875 var ntype
= self.n_type
876 var mtype
: nullable MType
877 if ntype
== null then
880 mtype
= v
.resolve_mtype
(ntype
)
881 if mtype
== null then return # Skip error
884 var nexpr
= self.n_expr
885 if nexpr
!= null then
886 if mtype
!= null then
887 var etype
= v
.visit_expr_subtype
(nexpr
, mtype
)
888 if etype
== mtype
then
890 v
.modelbuilder
.advice
(ntype
, "useless-type", "Warning: useless type definition for variable `{variable.name}`")
893 mtype
= v
.visit_expr
(nexpr
)
894 if mtype
== null then return # Skip error
899 if mtype
== null or mtype
isa MNullType then
900 var objclass
= v
.get_mclass
(self, "Object")
901 if objclass
== null then return # skip error
902 decltype
= objclass
.mclass_type
.as_nullable
903 if mtype
== null then mtype
= decltype
906 variable
.declared_type
= decltype
907 v
.set_variable
(self, variable
, mtype
)
909 #debug("var {variable}: {mtype}")
917 redef fun its_variable
do return self.variable
918 redef fun accept_typing
(v
)
920 var variable
= self.variable
921 if variable
== null then return # Skip error
923 var mtype
= v
.get_variable
(self, variable
)
924 if mtype
!= null then
925 #debug("{variable} is {mtype}")
927 #debug("{variable} is untyped")
934 redef class AVarAssignExpr
935 redef fun accept_typing
(v
)
937 var variable
= self.variable
938 assert variable
!= null
940 var mtype
= v
.visit_expr_subtype
(n_value
, variable
.declared_type
)
942 v
.set_variable
(self, variable
, mtype
)
948 redef class AReassignFormExpr
949 # The method designed by the reassign operator.
950 var reassign_callsite
: nullable CallSite
952 var read_type
: nullable MType = null
954 # Determine the `reassign_property`
955 # `readtype` is the type of the reading of the left value.
956 # `writetype` is the type of the writing of the left value.
957 # (Because of `ACallReassignExpr`, both can be different.
958 # Return the static type of the value to store.
959 private fun resolve_reassignment
(v
: TypeVisitor, readtype
, writetype
: MType): nullable MType
961 var reassign_name
= self.n_assign_op
.operator
963 self.read_type
= readtype
965 var callsite
= v
.get_method
(self.n_assign_op
, readtype
, reassign_name
, false)
966 if callsite
== null then return null # Skip error
967 self.reassign_callsite
= callsite
969 var msignature
= callsite
.msignature
970 var rettype
= msignature
.return_mtype
971 assert msignature
.arity
== 1 and rettype
!= null
973 var value_type
= v
.visit_expr_subtype
(self.n_value
, msignature
.mparameters
.first
.mtype
)
974 if value_type
== null then return null # Skip error
976 v
.check_subtype
(self, rettype
, writetype
, false)
981 redef class AVarReassignExpr
982 redef fun accept_typing
(v
)
984 var variable
= self.variable
985 assert variable
!= null
987 var readtype
= v
.get_variable
(self, variable
)
988 if readtype
== null then return
992 var writetype
= variable
.declared_type
993 if writetype
== null then return
995 var rettype
= self.resolve_reassignment
(v
, readtype
, writetype
)
997 v
.set_variable
(self, variable
, rettype
)
999 self.is_typed
= rettype
!= null
1004 redef class AContinueExpr
1005 redef fun accept_typing
(v
)
1007 var nexpr
= self.n_expr
1008 if nexpr
!= null then
1011 self.is_typed
= true
1015 redef class ABreakExpr
1016 redef fun accept_typing
(v
)
1018 var nexpr
= self.n_expr
1019 if nexpr
!= null then
1022 self.is_typed
= true
1026 redef class AReturnExpr
1027 redef fun accept_typing
(v
)
1029 var nexpr
= self.n_expr
1031 var mpropdef
= v
.mpropdef
1032 if mpropdef
isa MMethodDef then
1033 ret_type
= mpropdef
.msignature
.return_mtype
1034 else if mpropdef
isa MAttributeDef then
1035 ret_type
= mpropdef
.static_mtype
1039 if nexpr
!= null then
1040 if ret_type
!= null then
1041 v
.visit_expr_subtype
(nexpr
, ret_type
)
1044 v
.error
(nexpr
, "Error: `return` with value in a procedure.")
1047 else if ret_type
!= null then
1048 v
.error
(self, "Error: `return` without value in a function.")
1051 self.is_typed
= true
1055 redef class AAbortExpr
1056 redef fun accept_typing
(v
)
1058 self.is_typed
= true
1063 redef fun accept_typing
(v
)
1065 v
.visit_expr_bool
(n_expr
)
1067 v
.visit_stmt
(n_then
)
1068 v
.visit_stmt
(n_else
)
1070 self.is_typed
= true
1072 if n_then
!= null and n_else
== null then
1073 self.mtype
= n_then
.mtype
1078 redef class AIfexprExpr
1079 redef fun accept_typing
(v
)
1081 v
.visit_expr_bool
(n_expr
)
1083 var t1
= v
.visit_expr
(n_then
)
1084 var t2
= v
.visit_expr
(n_else
)
1086 if t1
== null or t2
== null then
1090 var t
= v
.merge_types
(self, [t1
, t2
])
1092 v
.error
(self, "Type Error: ambiguous type `{t1}` vs `{t2}`.")
1099 redef fun accept_typing
(v
)
1101 v
.visit_stmt
(n_block
)
1102 self.is_typed
= true
1106 redef class AWhileExpr
1107 redef fun accept_typing
(v
)
1110 v
.visit_expr_bool
(n_expr
)
1111 v
.visit_stmt
(n_block
)
1112 self.is_typed
= true
1116 redef class ALoopExpr
1117 redef fun accept_typing
(v
)
1120 v
.visit_stmt
(n_block
)
1121 self.is_typed
= true
1125 redef class AForExpr
1126 var coltype
: nullable MClassType
1128 var method_iterator
: nullable CallSite
1129 var method_is_ok
: nullable CallSite
1130 var method_item
: nullable CallSite
1131 var method_next
: nullable CallSite
1132 var method_key
: nullable CallSite
1133 var method_finish
: nullable CallSite
1135 var method_lt
: nullable CallSite
1136 var method_successor
: nullable CallSite
1138 private fun do_type_iterator
(v
: TypeVisitor, mtype
: MType)
1140 if mtype
isa MNullType then
1141 v
.error
(self, "Type Error: `for` cannot iterate over `null`.")
1146 var objcla
= v
.get_mclass
(self, "Object")
1147 if objcla
== null then return
1149 # check iterator method
1150 var itdef
= v
.get_method
(self, mtype
, "iterator", n_expr
isa ASelfExpr)
1151 if itdef
== null then
1152 v
.error
(self, "Type Error: `for` expects a type providing an `iterator` method, got `{mtype}`.")
1155 self.method_iterator
= itdef
1157 # check that iterator return something
1158 var ittype
= itdef
.msignature
.return_mtype
1159 if ittype
== null then
1160 v
.error
(self, "Type Error: `for` expects the method `iterator` to return an `Iterator` or `MapIterator` type.")
1165 var colit_cla
= v
.try_get_mclass
(self, "Iterator")
1166 var mapit_cla
= v
.try_get_mclass
(self, "MapIterator")
1170 if colit_cla
!= null and v
.is_subtype
(ittype
, colit_cla
.get_mtype
([objcla
.mclass_type
.as_nullable
])) then
1172 var coltype
= ittype
.supertype_to
(v
.mmodule
, v
.anchor
, colit_cla
)
1173 var variables
= self.variables
1174 if variables
.length
!= 1 then
1175 v
.error
(self, "Type Error: `for` expects only one variable when using `Iterator`.")
1177 variables
.first
.declared_type
= coltype
.arguments
.first
1182 if mapit_cla
!= null and v
.is_subtype
(ittype
, mapit_cla
.get_mtype
([objcla
.mclass_type
.as_nullable
, objcla
.mclass_type
.as_nullable
])) then
1184 var coltype
= ittype
.supertype_to
(v
.mmodule
, v
.anchor
, mapit_cla
)
1185 var variables
= self.variables
1186 if variables
.length
!= 2 then
1187 v
.error
(self, "Type Error: `for` expects two variables when using `MapIterator`.")
1189 variables
[0].declared_type
= coltype
.arguments
[0]
1190 variables
[1].declared_type
= coltype
.arguments
[1]
1195 if not is_col
and not is_map
then
1196 v
.error
(self, "Type Error: `for` expects the method `iterator` to return an `Iterator` or `MapIterator` type.")
1200 # anchor formal and virtual types
1201 if mtype
.need_anchor
then mtype
= v
.anchor_to
(mtype
)
1203 mtype
= mtype
.undecorate
1204 self.coltype
= mtype
.as(MClassType)
1206 # get methods is_ok, next, item
1207 var ikdef
= v
.get_method
(self, ittype
, "is_ok", false)
1208 if ikdef
== null then
1209 v
.error
(self, "Type Error: `for` expects a method `is_ok` in type `{ittype}`.")
1212 self.method_is_ok
= ikdef
1214 var itemdef
= v
.get_method
(self, ittype
, "item", false)
1215 if itemdef
== null then
1216 v
.error
(self, "Type Error: `for` expects a method `item` in type `{ittype}`.")
1219 self.method_item
= itemdef
1221 var nextdef
= v
.get_method
(self, ittype
, "next", false)
1222 if nextdef
== null then
1223 v
.error
(self, "Type Error: `for` expects a method `next` in type {ittype}.")
1226 self.method_next
= nextdef
1228 self.method_finish
= v
.try_get_method
(self, ittype
, "finish", false)
1231 var keydef
= v
.get_method
(self, ittype
, "key", false)
1232 if keydef
== null then
1233 v
.error
(self, "Type Error: `for` expects a method `key` in type `{ittype}`.")
1236 self.method_key
= keydef
1239 if self.variables
.length
== 1 and n_expr
isa ARangeExpr then
1240 var variable
= variables
.first
1241 var vtype
= variable
.declared_type
.as(not null)
1243 if n_expr
isa AOrangeExpr then
1244 self.method_lt
= v
.get_method
(self, vtype
, "<", false)
1246 self.method_lt
= v
.get_method
(self, vtype
, "<=", false)
1249 self.method_successor
= v
.get_method
(self, vtype
, "successor", false)
1253 redef fun accept_typing
(v
)
1256 var mtype
= v
.visit_expr
(n_expr
)
1257 if mtype
== null then return
1259 self.do_type_iterator
(v
, mtype
)
1261 v
.visit_stmt
(n_block
)
1263 self.mtype
= n_block
.mtype
1264 self.is_typed
= true
1268 redef class AWithExpr
1269 var method_start
: nullable CallSite
1270 var method_finish
: nullable CallSite
1272 redef fun accept_typing
(v
: TypeVisitor)
1274 var mtype
= v
.visit_expr
(n_expr
)
1275 if mtype
== null then return
1277 method_start
= v
.get_method
(self, mtype
, "start", n_expr
isa ASelfExpr)
1278 method_finish
= v
.get_method
(self, mtype
, "finish", n_expr
isa ASelfExpr)
1280 v
.visit_stmt
(n_block
)
1281 self.mtype
= n_block
.mtype
1282 self.is_typed
= true
1286 redef class AAssertExpr
1287 redef fun accept_typing
(v
)
1289 v
.visit_expr_bool
(n_expr
)
1291 v
.visit_stmt
(n_else
)
1292 self.is_typed
= true
1297 redef fun accept_typing
(v
)
1299 v
.visit_expr_bool
(n_expr
)
1300 v
.visit_expr_bool
(n_expr2
)
1301 self.mtype
= v
.type_bool
(self)
1305 redef class AImpliesExpr
1306 redef fun accept_typing
(v
)
1308 v
.visit_expr_bool
(n_expr
)
1309 v
.visit_expr_bool
(n_expr2
)
1310 self.mtype
= v
.type_bool
(self)
1314 redef class AAndExpr
1315 redef fun accept_typing
(v
)
1317 v
.visit_expr_bool
(n_expr
)
1318 v
.visit_expr_bool
(n_expr2
)
1319 self.mtype
= v
.type_bool
(self)
1324 redef class ANotExpr
1325 redef fun accept_typing
(v
)
1327 v
.visit_expr_bool
(n_expr
)
1328 self.mtype
= v
.type_bool
(self)
1332 redef class AOrElseExpr
1333 redef fun accept_typing
(v
)
1335 var t1
= v
.visit_expr
(n_expr
)
1336 var t2
= v
.visit_expr
(n_expr2
)
1338 if t1
== null or t2
== null then
1342 if t1
isa MNullType then
1345 else if v
.can_be_null
(t1
) then
1349 var t
= v
.merge_types
(self, [t1
, t2
])
1351 var c
= v
.get_mclass
(self, "Object")
1352 if c
== null then return # forward error
1354 if v
.can_be_null
(t2
) then
1357 #v.error(self, "Type Error: ambiguous type {t1} vs {t2}")
1362 redef fun accept_post_typing
(v
)
1364 var t1
= n_expr
.mtype
1368 v
.check_can_be_null
(n_expr
, t1
)
1373 redef class ATrueExpr
1374 redef fun accept_typing
(v
)
1376 self.mtype
= v
.type_bool
(self)
1380 redef class AFalseExpr
1381 redef fun accept_typing
(v
)
1383 self.mtype
= v
.type_bool
(self)
1387 redef class AIntegerExpr
1388 redef fun accept_typing
(v
)
1390 var mclass
: nullable MClass = null
1391 if value
isa Byte then
1392 mclass
= v
.get_mclass
(self, "Byte")
1393 else if value
isa Int then
1394 mclass
= v
.get_mclass
(self, "Int")
1395 else if value
isa Int8 then
1396 mclass
= v
.get_mclass
(self, "Int8")
1397 else if value
isa Int16 then
1398 mclass
= v
.get_mclass
(self, "Int16")
1399 else if value
isa UInt16 then
1400 mclass
= v
.get_mclass
(self, "UInt16")
1401 else if value
isa Int32 then
1402 mclass
= v
.get_mclass
(self, "Int32")
1403 else if value
isa UInt32 then
1404 mclass
= v
.get_mclass
(self, "UInt32")
1406 if mclass
== null then return # Forward error
1407 self.mtype
= mclass
.mclass_type
1411 redef class AFloatExpr
1412 redef fun accept_typing
(v
)
1414 var mclass
= v
.get_mclass
(self, "Float")
1415 if mclass
== null then return # Forward error
1416 self.mtype
= mclass
.mclass_type
1420 redef class ACharExpr
1421 redef fun accept_typing
(v
)
1423 var mclass
= v
.get_mclass
(self, "Char")
1424 if mclass
== null then return # Forward error
1425 self.mtype
= mclass
.mclass_type
1429 redef class AStringFormExpr
1430 redef fun accept_typing
(v
)
1432 var mclass
= v
.get_mclass
(self, "String")
1433 if mclass
== null then return # Forward error
1434 self.mtype
= mclass
.mclass_type
1438 redef class ASuperstringExpr
1439 redef fun accept_typing
(v
)
1441 var mclass
= v
.get_mclass
(self, "String")
1442 if mclass
== null then return # Forward error
1443 self.mtype
= mclass
.mclass_type
1444 var objclass
= v
.get_mclass
(self, "Object")
1445 if objclass
== null then return # Forward error
1446 var objtype
= objclass
.mclass_type
1447 for nexpr
in self.n_exprs
do
1448 v
.visit_expr_subtype
(nexpr
, objtype
)
1453 redef class AArrayExpr
1454 # The `with_capacity` method on Array
1455 var with_capacity_callsite
: nullable CallSite
1457 # The `push` method on arrays
1458 var push_callsite
: nullable CallSite
1460 # The element of each type
1461 var element_mtype
: nullable MType
1463 # Set that `self` is a part of comprehension array `na`
1464 # If `self` is a `for`, or a `if`, then `set_comprehension` is recursively applied.
1465 private fun set_comprehension
(n
: nullable AExpr)
1469 else if n
isa AForExpr then
1470 set_comprehension
(n
.n_block
)
1471 else if n
isa AIfExpr then
1472 set_comprehension
(n
.n_then
)
1473 set_comprehension
(n
.n_else
)
1476 n
.comprehension
= self
1479 redef fun accept_typing
(v
)
1481 var mtype
: nullable MType = null
1482 var ntype
= self.n_type
1483 if ntype
!= null then
1484 mtype
= v
.resolve_mtype
(ntype
)
1485 if mtype
== null then return # Skip error
1487 var mtypes
= new Array[nullable MType]
1489 for e
in self.n_exprs
do
1490 var t
= v
.visit_expr
(e
)
1494 set_comprehension
(e
)
1495 if mtype
!= null then
1496 if v
.check_subtype
(e
, t
, mtype
, false) == null then return # Forward error
1497 if t
== mtype
then useless
= true
1502 if mtype
== null then
1503 # Ensure monotony for type adaptation on loops
1504 if self.element_mtype
!= null then mtypes
.add
self.element_mtype
1505 mtype
= v
.merge_types
(self, mtypes
)
1507 if mtype
== null or mtype
isa MNullType then
1508 v
.error
(self, "Type Error: ambiguous array type {mtypes.join(" ")}")
1512 assert ntype
!= null
1513 v
.modelbuilder
.warning
(ntype
, "useless-type", "Warning: useless type declaration `{mtype}` in literal Array since it can be inferred from the elements type.")
1516 self.element_mtype
= mtype
1518 var mclass
= v
.get_mclass
(self, "Array")
1519 if mclass
== null then return # Forward error
1520 var array_mtype
= mclass
.get_mtype
([mtype
])
1522 with_capacity_callsite
= v
.get_method
(self, array_mtype
, "with_capacity", false)
1523 push_callsite
= v
.get_method
(self, array_mtype
, "push", false)
1525 self.mtype
= array_mtype
1529 redef class ARangeExpr
1530 var init_callsite
: nullable CallSite
1532 redef fun accept_typing
(v
)
1534 var discrete_class
= v
.get_mclass
(self, "Discrete")
1535 if discrete_class
== null then return # Forward error
1536 var discrete_type
= discrete_class
.intro
.bound_mtype
1537 var t1
= v
.visit_expr_subtype
(self.n_expr
, discrete_type
)
1538 var t2
= v
.visit_expr_subtype
(self.n_expr2
, discrete_type
)
1539 if t1
== null or t2
== null then return
1540 var mclass
= v
.get_mclass
(self, "Range")
1541 if mclass
== null then return # Forward error
1543 if v
.is_subtype
(t1
, t2
) then
1544 mtype
= mclass
.get_mtype
([t2
])
1545 else if v
.is_subtype
(t2
, t1
) then
1546 mtype
= mclass
.get_mtype
([t1
])
1548 v
.error
(self, "Type Error: cannot create range: `{t1}` vs `{t2}`.")
1554 # get the constructor
1556 if self isa ACrangeExpr then
1557 callsite
= v
.get_method
(self, mtype
, "init", false)
1558 else if self isa AOrangeExpr then
1559 callsite
= v
.get_method
(self, mtype
, "without_last", false)
1563 init_callsite
= callsite
1567 redef class ANullExpr
1568 redef fun accept_typing
(v
)
1570 self.mtype
= v
.mmodule
.model
.null_type
1574 redef class AIsaExpr
1575 # The static type to cast to.
1576 # (different from the static type of the expression that is `Bool`).
1577 var cast_type
: nullable MType
1578 redef fun accept_typing
(v
)
1580 v
.visit_expr
(n_expr
)
1582 var mtype
= v
.resolve_mtype
(n_type
)
1584 self.cast_type
= mtype
1586 var variable
= self.n_expr
.its_variable
1587 if variable
!= null then
1588 #var orig = self.n_expr.mtype
1589 #var from = if orig != null then orig.to_s else "invalid"
1590 #var to = if mtype != null then mtype.to_s else "invalid"
1591 #debug("adapt {variable}: {from} -> {to}")
1592 self.after_flow_context
.when_true
.set_var
(v
, variable
, mtype
)
1595 self.mtype
= v
.type_bool
(self)
1598 redef fun accept_post_typing
(v
)
1600 v
.check_expr_cast
(self, self.n_expr
, self.n_type
)
1604 redef class AAsCastExpr
1605 redef fun accept_typing
(v
)
1607 v
.visit_expr
(n_expr
)
1609 self.mtype
= v
.resolve_mtype
(n_type
)
1612 redef fun accept_post_typing
(v
)
1614 v
.check_expr_cast
(self, self.n_expr
, self.n_type
)
1618 redef class AAsNotnullExpr
1619 redef fun accept_typing
(v
)
1621 var mtype
= v
.visit_expr
(self.n_expr
)
1622 if mtype
== null then return # Forward error
1624 if mtype
isa MNullType then
1625 v
.error
(self, "Type Error: `as(not null)` on `null`.")
1629 if v
.can_be_null
(mtype
) then
1630 mtype
= mtype
.as_notnull
1636 redef fun accept_post_typing
(v
)
1638 var mtype
= n_expr
.mtype
1639 if mtype
== null then return
1640 v
.check_can_be_null
(n_expr
, mtype
)
1644 redef class AParExpr
1645 redef fun accept_typing
(v
)
1647 self.mtype
= v
.visit_expr
(self.n_expr
)
1651 redef class AOnceExpr
1652 redef fun accept_typing
(v
)
1654 self.mtype
= v
.visit_expr
(self.n_expr
)
1658 redef class ASelfExpr
1659 redef var its_variable
: nullable Variable
1660 redef fun accept_typing
(v
)
1662 if v
.is_toplevel_context
and not self isa AImplicitSelfExpr then
1663 v
.error
(self, "Error: `self` cannot be used in top-level method.")
1665 var variable
= v
.selfvariable
1666 self.its_variable
= variable
1667 self.mtype
= v
.get_variable
(self, variable
)
1671 redef class AImplicitSelfExpr
1672 # Is the implicit receiver `sys`?
1674 # By default, the implicit receiver is `self`.
1675 # But when there is not method for `self`, `sys` is used as a fall-back.
1676 # Is this case this flag is set to `true`.
1680 ## MESSAGE SENDING AND PROPERTY
1682 redef class ASendExpr
1683 # The property invoked by the send.
1684 var callsite
: nullable CallSite
1686 redef fun accept_typing
(v
)
1688 var nrecv
= self.n_expr
1689 var recvtype
= v
.visit_expr
(nrecv
)
1690 var name
= self.property_name
1691 var node
= self.property_node
1693 if recvtype
== null then return # Forward error
1696 var unsafe_type
= v
.anchor_to
(recvtype
)
1697 var mproperty
= v
.try_get_mproperty_by_name2
(node
, unsafe_type
, name
)
1698 if mproperty
== null and nrecv
isa AImplicitSelfExpr then
1699 # Special fall-back search in `sys` when noting found in the implicit receiver.
1700 var sysclass
= v
.try_get_mclass
(node
, "Sys")
1701 if sysclass
!= null then
1702 var systype
= sysclass
.mclass_type
1703 mproperty
= v
.try_get_mproperty_by_name2
(node
, systype
, name
)
1704 if mproperty
!= null then
1705 callsite
= v
.get_method
(node
, systype
, name
, false)
1706 if callsite
== null then return # Forward error
1707 # Update information, we are looking at `sys` now, not `self`
1709 nrecv
.its_variable
= null
1710 nrecv
.mtype
= systype
1715 if callsite
== null then
1716 # If still nothing, just exit
1717 callsite
= v
.get_method
(node
, recvtype
, name
, nrecv
isa ASelfExpr)
1718 if callsite
== null then return
1721 self.callsite
= callsite
1722 var msignature
= callsite
.msignature
1724 var args
= compute_raw_arguments
1726 callsite
.check_signature
(v
, args
)
1728 if callsite
.mproperty
.is_init
then
1729 var vmpropdef
= v
.mpropdef
1730 if not (vmpropdef
isa MMethodDef and vmpropdef
.mproperty
.is_init
) then
1731 v
.error
(node
, "Error: an `init` can only be called from another `init`.")
1733 if vmpropdef
isa MMethodDef and vmpropdef
.mproperty
.is_root_init
and not callsite
.mproperty
.is_root_init
then
1734 v
.error
(node
, "Error: `{vmpropdef}` cannot call a factory `{callsite.mproperty}`.")
1738 var ret
= msignature
.return_mtype
1742 self.is_typed
= true
1746 # The name of the property
1747 # Each subclass simply provide the correct name.
1748 private fun property_name
: String is abstract
1750 # The node identifying the name (id, operator, etc) for messages.
1752 # Is `self` by default
1753 private fun property_node
: ANode do return self
1755 # An array of all arguments (excluding self)
1756 fun raw_arguments
: Array[AExpr] do return compute_raw_arguments
1758 private fun compute_raw_arguments
: Array[AExpr] is abstract
1761 redef class ABinopExpr
1762 redef fun compute_raw_arguments
do return [n_expr2
]
1763 redef fun property_name
do return operator
1764 redef fun property_node
do return n_op
1767 redef class AEqFormExpr
1768 redef fun accept_typing
(v
)
1774 redef fun accept_post_typing
(v
)
1776 var mtype
= n_expr
.mtype
1777 var mtype2
= n_expr2
.mtype
1779 if mtype
== null or mtype2
== null then return
1781 if not mtype2
isa MNullType then return
1783 v
.check_can_be_null
(n_expr
, mtype
)
1787 redef class AUnaryopExpr
1788 redef fun property_name
do return "unary {operator}"
1789 redef fun compute_raw_arguments
do return new Array[AExpr]
1793 redef class ACallExpr
1794 redef fun property_name
do return n_qid
.n_id
.text
1795 redef fun property_node
do return n_qid
1796 redef fun compute_raw_arguments
do return n_args
.to_a
1799 redef class ACallAssignExpr
1800 redef fun property_name
do return n_qid
.n_id
.text
+ "="
1801 redef fun property_node
do return n_qid
1802 redef fun compute_raw_arguments
1804 var res
= n_args
.to_a
1810 redef class ABraExpr
1811 redef fun property_name
do return "[]"
1812 redef fun compute_raw_arguments
do return n_args
.to_a
1815 redef class ABraAssignExpr
1816 redef fun property_name
do return "[]="
1817 redef fun compute_raw_arguments
1819 var res
= n_args
.to_a
1825 redef class ASendReassignFormExpr
1826 # The property invoked for the writing
1827 var write_callsite
: nullable CallSite
1829 redef fun accept_typing
(v
)
1831 var recvtype
= v
.visit_expr
(self.n_expr
)
1832 var name
= self.property_name
1833 var node
= self.property_node
1835 if recvtype
== null then return # Forward error
1837 var for_self
= self.n_expr
isa ASelfExpr
1838 var callsite
= v
.get_method
(node
, recvtype
, name
, for_self
)
1840 if callsite
== null then return
1841 self.callsite
= callsite
1843 var args
= compute_raw_arguments
1845 callsite
.check_signature
(v
, args
)
1847 var readtype
= callsite
.msignature
.return_mtype
1848 if readtype
== null then
1849 v
.error
(node
, "Error: `{name}` is not a function.")
1853 var wcallsite
= v
.get_method
(node
, recvtype
, name
+ "=", self.n_expr
isa ASelfExpr)
1854 if wcallsite
== null then return
1855 self.write_callsite
= wcallsite
1857 var wtype
= self.resolve_reassignment
(v
, readtype
, wcallsite
.msignature
.mparameters
.last
.mtype
)
1858 if wtype
== null then return
1860 args
= args
.to_a
# duplicate so raw_arguments keeps only the getter args
1861 args
.add
(self.n_value
)
1862 wcallsite
.check_signature
(v
, args
)
1864 self.is_typed
= true
1868 redef class ACallReassignExpr
1869 redef fun property_name
do return n_qid
.n_id
.text
1870 redef fun property_node
do return n_qid
.n_id
1871 redef fun compute_raw_arguments
do return n_args
.to_a
1874 redef class ABraReassignExpr
1875 redef fun property_name
do return "[]"
1876 redef fun compute_raw_arguments
do return n_args
.to_a
1879 redef class AInitExpr
1880 redef fun property_name
do return "init"
1881 redef fun property_node
do return n_kwinit
1882 redef fun compute_raw_arguments
do return n_args
.to_a
1886 fun to_a
: Array[AExpr] do return self.n_exprs
.to_a
1891 redef class ASuperExpr
1892 # The method to call if the super is in fact a 'super init call'
1893 # Note: if the super is a normal call-next-method, then this attribute is null
1894 var callsite
: nullable CallSite
1896 # The method to call is the super is a standard `call-next-method` super-call
1897 # Note: if the super is a special super-init-call, then this attribute is null
1898 var mpropdef
: nullable MMethodDef
1900 redef fun accept_typing
(v
)
1902 var anchor
= v
.anchor
1903 assert anchor
!= null
1904 var recvtype
= v
.get_variable
(self, v
.selfvariable
)
1905 assert recvtype
!= null
1906 var mproperty
= v
.mpropdef
.mproperty
1907 if not mproperty
isa MMethod then
1908 v
.error
(self, "Error: `super` only usable in a `method`.")
1911 var superprops
= mproperty
.lookup_super_definitions
(v
.mmodule
, anchor
)
1912 if superprops
.length
== 0 then
1913 if mproperty
.is_init
and v
.mpropdef
.is_intro
then
1914 process_superinit
(v
)
1917 v
.error
(self, "Error: no super method to call for `{mproperty}`.")
1920 # FIXME: covariance of return type in linear extension?
1921 var superprop
= superprops
.first
1923 var msignature
= superprop
.msignature
.as(not null)
1924 msignature
= v
.resolve_for
(msignature
, recvtype
, true).as(MSignature)
1925 var args
= self.n_args
.to_a
1926 if args
.length
> 0 then
1927 signaturemap
= v
.check_signature
(self, args
, mproperty
, msignature
)
1929 self.mtype
= msignature
.return_mtype
1930 self.is_typed
= true
1931 v
.mpropdef
.has_supercall
= true
1932 mpropdef
= v
.mpropdef
.as(MMethodDef)
1935 # The mapping used on the call to associate arguments to parameters.
1936 # If null then no specific association is required.
1937 var signaturemap
: nullable SignatureMap
1939 private fun process_superinit
(v
: TypeVisitor)
1941 var anchor
= v
.anchor
1942 assert anchor
!= null
1943 var recvtype
= v
.get_variable
(self, v
.selfvariable
)
1944 assert recvtype
!= null
1945 var mpropdef
= v
.mpropdef
1946 assert mpropdef
isa MMethodDef
1947 var mproperty
= mpropdef
.mproperty
1948 var superprop
: nullable MMethodDef = null
1949 for msupertype
in mpropdef
.mclassdef
.supertypes
do
1950 msupertype
= msupertype
.anchor_to
(v
.mmodule
, anchor
)
1951 var errcount
= v
.modelbuilder
.toolcontext
.error_count
1952 var candidate
= v
.try_get_mproperty_by_name2
(self, msupertype
, mproperty
.name
).as(nullable MMethod)
1953 if candidate
== null then
1954 if v
.modelbuilder
.toolcontext
.error_count
> errcount
then return # Forward error
1955 continue # Try next super-class
1957 if superprop
!= null and candidate
.is_root_init
then
1960 if superprop
!= null and superprop
.mproperty
!= candidate
and not superprop
.mproperty
.is_root_init
then
1961 v
.error
(self, "Error: conflicting super constructor to call for `{mproperty}`: `{candidate.full_name}`, `{superprop.mproperty.full_name}`")
1964 var candidatedefs
= candidate
.lookup_definitions
(v
.mmodule
, anchor
)
1965 if superprop
!= null and superprop
.mproperty
== candidate
then
1966 if superprop
== candidatedefs
.first
then continue
1967 candidatedefs
.add
(superprop
)
1969 if candidatedefs
.length
> 1 then
1970 v
.error
(self, "Error: conflicting property definitions for property `{mproperty}` in `{recvtype}`: {candidatedefs.join(", ")}")
1973 superprop
= candidatedefs
.first
1975 if superprop
== null then
1976 v
.error
(self, "Error: no super method to call for `{mproperty}`.")
1980 var msignature
= superprop
.new_msignature
or else superprop
.msignature
.as(not null)
1981 msignature
= v
.resolve_for
(msignature
, recvtype
, true).as(MSignature)
1983 var callsite
= new CallSite(self, recvtype
, v
.mmodule
, v
.anchor
, true, superprop
.mproperty
, superprop
, msignature
, false)
1984 self.callsite
= callsite
1986 var args
= self.n_args
.to_a
1987 if args
.length
> 0 then
1988 callsite
.check_signature
(v
, args
)
1990 # Check there is at least enough parameters
1991 if mpropdef
.msignature
.arity
< msignature
.arity
then
1992 v
.error
(self, "Error: not enough implicit arguments to pass. Got `{mpropdef.msignature.arity}`, expected at least `{msignature.arity}`. Signature is `{msignature}`.")
1995 # Check that each needed parameter is conform
1997 for sp
in msignature
.mparameters
do
1998 var p
= mpropdef
.msignature
.mparameters
[i
]
1999 if not v
.is_subtype
(p
.mtype
, sp
.mtype
) then
2000 v
.error
(self, "Type Error: expected argument #{i} of type `{sp.mtype}`, got implicit argument `{p.name}` of type `{p.mtype}`. Signature is {msignature}")
2007 self.is_typed
= true
2013 redef class ANewExpr
2014 # The constructor invoked by the new.
2015 var callsite
: nullable CallSite
2017 # The designated type
2018 var recvtype
: nullable MClassType
2020 redef fun accept_typing
(v
)
2022 var recvtype
= v
.resolve_mtype
(self.n_type
)
2023 if recvtype
== null then return
2025 if not recvtype
isa MClassType then
2026 if recvtype
isa MNullableType then
2027 v
.error
(self, "Type Error: cannot instantiate the nullable type `{recvtype}`.")
2029 else if recvtype
isa MFormalType then
2030 v
.error
(self, "Type Error: cannot instantiate the formal type `{recvtype}`.")
2033 v
.error
(self, "Type Error: cannot instantiate the type `{recvtype}`.")
2038 self.recvtype
= recvtype
2039 var kind
= recvtype
.mclass
.kind
2042 var nqid
= self.n_qid
2044 if nqid
!= null then
2045 name
= nqid
.n_id
.text
2051 if name
== "intern" then
2052 if kind
!= concrete_kind
then
2053 v
.error
(self, "Type Error: cannot instantiate {kind} {recvtype}.")
2056 if n_args
.n_exprs
.not_empty
then
2057 v
.error
(n_args
, "Type Error: the intern constructor expects no arguments.")
2061 self.mtype
= recvtype
2065 var callsite
= v
.get_method
(node
, recvtype
, name
, false)
2066 if callsite
== null then return
2068 if not callsite
.mproperty
.is_new
then
2069 if kind
!= concrete_kind
then
2070 v
.error
(self, "Type Error: cannot instantiate {kind} `{recvtype}`.")
2073 self.mtype
= recvtype
2075 self.mtype
= callsite
.msignature
.return_mtype
2076 assert self.mtype
!= null
2079 self.callsite
= callsite
2081 if not callsite
.mproperty
.is_init_for
(recvtype
.mclass
) then
2082 v
.error
(self, "Error: `{name}` is not a constructor.")
2086 var args
= n_args
.to_a
2087 callsite
.check_signature
(v
, args
)
2093 redef class AAttrFormExpr
2094 # The attribute accessed.
2095 var mproperty
: nullable MAttribute
2097 # The static type of the attribute.
2098 var attr_type
: nullable MType
2100 # Resolve the attribute accessed.
2101 private fun resolve_property
(v
: TypeVisitor)
2103 var recvtype
= v
.visit_expr
(self.n_expr
)
2104 if recvtype
== null then return # Skip error
2105 var node
= self.n_id
2106 var name
= node
.text
2107 if recvtype
isa MNullType then
2108 v
.error
(node
, "Error: attribute `{name}` access on `null`.")
2112 var unsafe_type
= v
.anchor_to
(recvtype
)
2113 var mproperty
= v
.try_get_mproperty_by_name2
(node
, unsafe_type
, name
)
2114 if mproperty
== null then
2115 v
.modelbuilder
.error
(node
, "Error: attribute `{name}` does not exist in `{recvtype}`.")
2118 assert mproperty
isa MAttribute
2119 self.mproperty
= mproperty
2121 var mpropdefs
= mproperty
.lookup_definitions
(v
.mmodule
, unsafe_type
)
2122 assert mpropdefs
.length
== 1
2123 var mpropdef
= mpropdefs
.first
2124 var attr_type
= mpropdef
.static_mtype
2125 if attr_type
== null then return # skip error
2126 attr_type
= v
.resolve_for
(attr_type
, recvtype
, self.n_expr
isa ASelfExpr)
2127 self.attr_type
= attr_type
2131 redef class AAttrExpr
2132 redef fun accept_typing
(v
)
2134 self.resolve_property
(v
)
2135 self.mtype
= self.attr_type
2140 redef class AAttrAssignExpr
2141 redef fun accept_typing
(v
)
2143 self.resolve_property
(v
)
2144 var mtype
= self.attr_type
2146 v
.visit_expr_subtype
(self.n_value
, mtype
)
2147 self.is_typed
= mtype
!= null
2151 redef class AAttrReassignExpr
2152 redef fun accept_typing
(v
)
2154 self.resolve_property
(v
)
2155 var mtype
= self.attr_type
2156 if mtype
== null then return # Skip error
2158 var rettype
= self.resolve_reassignment
(v
, mtype
, mtype
)
2160 self.is_typed
= rettype
!= null
2164 redef class AIssetAttrExpr
2165 redef fun accept_typing
(v
)
2167 self.resolve_property
(v
)
2168 var mtype
= self.attr_type
2169 if mtype
== null then return # Skip error
2171 var recvtype
= self.n_expr
.mtype
.as(not null)
2172 var bound
= v
.resolve_for
(mtype
, recvtype
, false)
2173 if bound
isa MNullableType then
2174 v
.error
(n_id
, "Type Error: `isset` on a nullable attribute.")
2176 self.mtype
= v
.type_bool
(self)
2180 redef class AVarargExpr
2181 redef fun accept_typing
(v
)
2183 # This kind of pseudo-expression can be only processed trough a signature
2184 # See `check_signature`
2185 # Other cases are a syntax error.
2186 v
.error
(self, "Syntax Error: unexpected `...`.")
2192 redef class ADebugTypeExpr
2193 redef fun accept_typing
(v
)
2195 var expr
= v
.visit_expr
(self.n_expr
)
2196 if expr
== null then return
2197 var unsafe
= v
.anchor_to
(expr
)
2198 var ntype
= self.n_type
2199 var mtype
= v
.resolve_mtype
(ntype
)
2200 if mtype
!= null and mtype
!= expr
then
2201 var umtype
= v
.anchor_to
(mtype
)
2202 v
.modelbuilder
.warning
(self, "debug", "Found type {expr} (-> {unsafe}), expected {mtype} (-> {umtype})")
2204 self.is_typed
= true