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 sup
isa MBottomType then return null # Skip error
121 if sub
.need_anchor
then
122 var u
= anchor_to
(sub
)
123 self.modelbuilder
.error
(node
, "Type Error: expected `{sup}`, got `{sub}: {u}`.")
125 self.modelbuilder
.error
(node
, "Type Error: expected `{sup}`, got `{sub}`.")
130 # Visit an expression and do not care about the return value
131 fun visit_stmt
(nexpr
: nullable AExpr)
133 if nexpr
== null then return
134 nexpr
.accept_typing
(self)
137 # Visit an expression and expects that it is not a statement
138 # Return the type of the expression
139 # Display an error and return null if:
140 # * the type cannot be determined or
141 # * `nexpr` is a statement
142 fun visit_expr
(nexpr
: AExpr): nullable MType
144 nexpr
.accept_typing
(self)
145 var mtype
= nexpr
.mtype
146 if mtype
!= null then return mtype
147 if not nexpr
.is_typed
then
148 if not self.modelbuilder
.toolcontext
.error_count
> 0 then # check that there is really an error
149 if self.modelbuilder
.toolcontext
.verbose_level
> 1 then
150 nexpr
.debug
("No return type but no error.")
153 return null # forward error
155 self.error
(nexpr
, "Error: expected an expression.")
159 # Visit an expression and expect its static type is a least a `sup`
160 # Return the type of the expression or null if
161 # * the type cannot be determined or
162 # * `nexpr` is a statement or
163 # * `nexpr` is not a `sup`
164 fun visit_expr_subtype
(nexpr
: AExpr, sup
: nullable MType): nullable MType
166 var sub
= visit_expr
(nexpr
)
167 if sub
== null then return null # Forward error
169 if sup
== null then return null # Forward error
171 var res
= check_subtype
(nexpr
, sub
, sup
, true)
173 nexpr
.implicit_cast_to
= res
178 # Visit an expression and expect its static type is a `Bool`
179 # Return the type of the expression or null if
180 # * the type cannot be determined or
181 # * `nexpr` is a statement or
182 # * `nexpr` is not a `Bool`
183 fun visit_expr_bool
(nexpr
: AExpr): nullable MType
185 return self.visit_expr_subtype
(nexpr
, self.type_bool
(nexpr
))
189 fun check_expr_cast
(node
: ANode, nexpr
: AExpr, ntype
: AType): nullable MType
191 var sub
= nexpr
.mtype
192 if sub
== null then return null # Forward error
194 var sup
= ntype
.mtype
195 if sup
== null then return null # Forward error
198 self.modelbuilder
.warning
(node
, "useless-type-test", "Warning: expression is already a `{sup}`.")
199 else if self.is_subtype
(sub
, sup
) then
200 self.modelbuilder
.warning
(node
, "useless-type-test", "Warning: expression is already a `{sup}` since it is a `{sub}`.")
205 # Can `mtype` be null (up to the current knowledge)?
206 fun can_be_null
(mtype
: MType): Bool
208 if mtype
isa MNullableType or mtype
isa MNullType then return true
209 if mtype
isa MFormalType then
210 var x
= anchor_to
(mtype
)
211 if x
isa MNullableType or x
isa MNullType then return true
216 # Check that `mtype` can be null (up to the current knowledge).
218 # If not then display a `useless-null-test` warning on node and return false.
220 fun check_can_be_null
(anode
: ANode, mtype
: MType): Bool
222 if mtype
isa MNullType then
223 modelbuilder
.warning
(anode
, "useless-null-test", "Warning: expression is always `null`.")
226 if can_be_null
(mtype
) then return true
228 if mtype
isa MFormalType then
229 var res
= anchor_to
(mtype
)
230 modelbuilder
.warning
(anode
, "useless-null-test", "Warning: expression is not null, since it is a `{mtype}: {res}`.")
232 modelbuilder
.warning
(anode
, "useless-null-test", "Warning: expression is not null, since it is a `{mtype}`.")
237 # Special verification on != and == for null
239 fun null_test
(anode
: ABinopExpr)
241 var mtype
= anode
.n_expr
.mtype
242 var mtype2
= anode
.n_expr2
.mtype
244 if mtype
== null or mtype2
== null then return
246 if not mtype2
isa MNullType then return
248 # Check of useless null
249 if not can_be_null
(mtype
) then return
251 if mtype
isa MNullType then
252 # Because of type adaptation, we cannot just stop here
253 # so return use `null` as a bottom type that will be merged easily (cf) `merge_types`
256 mtype
= mtype
.as_notnull
259 # Check for type adaptation
260 var variable
= anode
.n_expr
.its_variable
261 if variable
== null then return
263 # One is null (mtype2 see above) the other is not null
264 if anode
isa AEqExpr then
265 anode
.after_flow_context
.when_true
.set_var
(self, variable
, mtype2
)
266 anode
.after_flow_context
.when_false
.set_var
(self, variable
, mtype
)
267 else if anode
isa ANeExpr then
268 anode
.after_flow_context
.when_false
.set_var
(self, variable
, mtype2
)
269 anode
.after_flow_context
.when_true
.set_var
(self, variable
, mtype
)
275 fun try_get_mproperty_by_name2
(anode
: ANode, mtype
: MType, name
: String): nullable MProperty
277 return self.modelbuilder
.try_get_mproperty_by_name2
(anode
, mmodule
, mtype
, name
)
280 fun resolve_mtype
(node
: AType): nullable MType
282 return self.modelbuilder
.resolve_mtype
(mmodule
, mclassdef
, node
)
285 fun try_get_mclass
(node
: ANode, name
: String): nullable MClass
287 var mclass
= modelbuilder
.try_get_mclass_by_name
(node
, mmodule
, name
)
291 fun get_mclass
(node
: ANode, name
: String): nullable MClass
293 var mclass
= modelbuilder
.get_mclass_by_name
(node
, mmodule
, name
)
297 fun type_bool
(node
: ANode): nullable MType
299 var mclass
= self.get_mclass
(node
, "Bool")
300 if mclass
== null then return null
301 return mclass
.mclass_type
304 fun get_method
(node
: ANode, recvtype
: MType, name
: String, recv_is_self
: Bool): nullable CallSite
306 var unsafe_type
= self.anchor_to
(recvtype
)
308 #debug("recv: {recvtype} (aka {unsafe_type})")
309 if recvtype
isa MNullType then
310 var objclass
= get_mclass
(node
, "Object")
311 if objclass
== null then return null # Forward error
312 unsafe_type
= objclass
.mclass_type
315 var mproperty
= self.try_get_mproperty_by_name2
(node
, unsafe_type
, name
)
316 if name
== "new" and mproperty
== null then
318 mproperty
= self.try_get_mproperty_by_name2
(node
, unsafe_type
, name
)
321 if mproperty
== null then
323 self.modelbuilder
.error
(node
, "Error: method or variable `{name}` unknown in `{recvtype}`.")
324 else if recvtype
.need_anchor
then
325 self.modelbuilder
.error
(node
, "Error: method `{name}` does not exists in `{recvtype}: {unsafe_type}`.")
327 self.modelbuilder
.error
(node
, "Error: method `{name}` does not exists in `{recvtype}`.")
332 assert mproperty
isa MMethod
334 # `null` only accepts some methods of object.
335 if recvtype
isa MNullType and not mproperty
.is_null_safe
then
336 self.error
(node
, "Error: method `{name}` called on `null`.")
338 else if unsafe_type
isa MNullableType and not mproperty
.is_null_safe
then
339 modelbuilder
.advice
(node
, "call-on-nullable", "Warning: method call on a nullable receiver `{recvtype}`.")
342 if is_toplevel_context
and recv_is_self
and not mproperty
.is_toplevel
then
343 error
(node
, "Error: `{name}` is not a top-level method, thus need a receiver.")
345 if not recv_is_self
and mproperty
.is_toplevel
then
346 error
(node
, "Error: cannot call `{name}`, a top-level method, with a receiver.")
349 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
350 self.modelbuilder
.error
(node
, "Error: method `{name}` is protected and can only accessed by `self`.")
354 var info
= mproperty
.deprecation
355 if info
!= null and self.mpropdef
.mproperty
.deprecation
== null then
358 self.modelbuilder
.warning
(node
, "deprecated-method", "Deprecation Warning: method `{name}` is deprecated: {mdoc.content.first}")
360 self.modelbuilder
.warning
(node
, "deprecated-method", "Deprecation Warning: method `{name}` is deprecated.")
364 var propdefs
= mproperty
.lookup_definitions
(self.mmodule
, unsafe_type
)
366 if propdefs
.length
== 0 then
367 self.modelbuilder
.error
(node
, "Type Error: no definition found for property `{name}` in `{unsafe_type}`.")
369 else if propdefs
.length
== 1 then
370 mpropdef
= propdefs
.first
372 self.modelbuilder
.warning
(node
, "property-conflict", "Warning: conflicting property definitions for property `{name}` in `{unsafe_type}`: {propdefs.join(" ")}")
373 mpropdef
= mproperty
.intro
377 var msignature
= mpropdef
.new_msignature
or else mpropdef
.msignature
378 if msignature
== null then return null # skip error
379 msignature
= resolve_for
(msignature
, recvtype
, recv_is_self
).as(MSignature)
381 var erasure_cast
= false
382 var rettype
= mpropdef
.msignature
.return_mtype
383 if not recv_is_self
and rettype
!= null then
384 rettype
= rettype
.undecorate
385 if rettype
isa MParameterType then
386 var erased_rettype
= msignature
.return_mtype
387 assert erased_rettype
!= null
388 #node.debug("Erasure cast: Really a {rettype} but unsafely a {erased_rettype}")
393 var callsite
= new CallSite(node
.hot_location
, recvtype
, mmodule
, anchor
, recv_is_self
, mproperty
, mpropdef
, msignature
, erasure_cast
)
397 fun try_get_method
(node
: ANode, recvtype
: MType, name
: String, recv_is_self
: Bool): nullable CallSite
399 var unsafe_type
= self.anchor_to
(recvtype
)
400 var mproperty
= self.try_get_mproperty_by_name2
(node
, unsafe_type
, name
)
401 if mproperty
== null then return null
402 return get_method
(node
, recvtype
, name
, recv_is_self
)
406 # Visit the expressions of args and check their conformity with the corresponding type in signature
407 # The point of this method is to handle varargs correctly
408 # Note: The signature must be correctly adapted
409 fun check_signature
(node
: ANode, args
: Array[AExpr], mproperty
: MProperty, msignature
: MSignature): nullable SignatureMap
411 var vararg_rank
= msignature
.vararg_rank
412 if vararg_rank
>= 0 then
413 if args
.length
< msignature
.arity
then
414 modelbuilder
.error
(node
, "Error: expected at least {msignature.arity} argument(s) for `{mproperty}{msignature}`; got {args.length}. See introduction at `{mproperty.full_name}`.")
417 else if args
.length
!= msignature
.arity
then
419 if args
.length
> msignature
.arity
then
420 modelbuilder
.error
(node
, "Error: expected {msignature.arity} argument(s) for `{mproperty}{msignature}`; got {args.length}. See introduction at `{mproperty.full_name}`.")
423 # Other cases are managed later
427 #debug("CALL {unsafe_type}.{msignature}")
429 # Associate each parameter to a position in the arguments
430 var map
= new SignatureMap
432 # Special case for the isolated last argument
433 # TODO: reify this method characteristics (where? the param, the signature, the method?)
434 var last_is_padded
= mproperty
.name
.chars
.last
== '='
435 var nbargs
= args
.length
436 if last_is_padded
then
438 assert not args
.last
isa ANamedargExpr
439 map
.map
[msignature
.arity
- 1] = args
.length
- 1
440 self.visit_expr_subtype
(args
.last
, msignature
.mparameters
.last
.mtype
)
443 # First, handle named arguments
444 for i
in [0..args
.length
[ do
446 if not e
isa ANamedargExpr then continue
447 var name
= e
.n_id
.text
448 var param
= msignature
.mparameter_by_name
(name
)
449 if param
== null then
450 modelbuilder
.error
(e
.n_id
, "Error: no parameter `{name}` for `{mproperty}{msignature}`.")
453 var idx
= msignature
.mparameters
.index_of
(param
)
454 var prev
= map
.map
.get_or_null
(idx
)
456 modelbuilder
.error
(e
, "Error: parameter `{name}` already associated with argument #{prev} for `{mproperty}{msignature}`.")
460 e
.mtype
= self.visit_expr_subtype
(e
.n_expr
, param
.mtype
)
463 # Number of minimum mandatory remaining parameters
466 # Second, associate remaining parameters
467 var vararg_decl
= args
.length
- msignature
.arity
469 for i
in [0..msignature
.arity
[ do
470 # Skip parameters associated by name
471 if map
.map
.has_key
(i
) then continue
473 var param
= msignature
.mparameters
[i
]
475 # Search the next free argument: skip named arguments since they are already associated
476 while j
< nbargs
and args
[j
] isa ANamedargExpr do j
+= 1
478 if not param
.mtype
isa MNullableType then
488 if i
== vararg_rank
then
490 continue # skip the vararg
493 var paramtype
= param
.mtype
494 self.visit_expr_subtype
(arg
, paramtype
)
497 if min_arity
> 0 then
498 if last_is_padded
then min_arity
+= 1
499 if min_arity
< msignature
.arity
then
500 modelbuilder
.error
(node
, "Error: expected at least {min_arity} argument(s) for `{mproperty}{msignature}`; got {args.length}. See introduction at `{mproperty.full_name}`.")
502 modelbuilder
.error
(node
, "Error: expected {min_arity} argument(s) for `{mproperty}{msignature}`; got {args.length}. See introduction at `{mproperty.full_name}`.")
507 # Third, check varargs
508 if vararg_rank
>= 0 then
509 var paramtype
= msignature
.mparameters
[vararg_rank
].mtype
510 var first
= args
[vararg_rank
]
511 if vararg_decl
== 0 then
512 var mclass
= get_mclass
(node
, "Array")
513 if mclass
== null then return null # Forward error
514 var array_mtype
= mclass
.get_mtype
([paramtype
])
515 if first
isa AVarargExpr then
516 self.visit_expr_subtype
(first
.n_expr
, array_mtype
)
517 first
.mtype
= first
.n_expr
.mtype
519 # only one vararg, maybe `...` was forgot, so be gentle!
520 var t
= visit_expr
(first
)
521 if t
== null then return null # Forward error
522 if not is_subtype
(t
, paramtype
) and is_subtype
(t
, array_mtype
) then
523 # Not acceptable but could be a `...`
524 error
(first
, "Type Error: expected `{paramtype}`, got `{t}`. Is an ellipsis `...` missing on the argument?")
527 # Standard valid vararg, finish the job
529 self.visit_expr_subtype
(first
, paramtype
)
532 first
.vararg_decl
= vararg_decl
+ 1
533 for i
in [vararg_rank
..vararg_rank
+vararg_decl
] do
534 self.visit_expr_subtype
(args
[i
], paramtype
)
542 fun error
(node
: ANode, message
: String)
544 self.modelbuilder
.error
(node
, message
)
547 fun get_variable
(node
: AExpr, variable
: Variable): nullable MType
549 if not variable
.is_adapted
then return variable
.declared_type
551 var flow
= node
.after_flow_context
552 if flow
== null then return null # skip error
554 if flow
.vars
.has_key
(variable
) then
555 return flow
.vars
[variable
]
557 #node.debug("*** START Collected for {variable}")
558 var mtypes
= flow
.collect_types
(variable
)
559 #node.debug("**** END Collected for {variable}")
560 if mtypes
.length
== 0 then
561 return variable
.declared_type
562 else if mtypes
.length
== 1 then
565 var res
= merge_types
(node
,mtypes
)
566 if res
== null then res
= variable
.declared_type
572 # Some variables where type-adapted during the visit
575 # Some loops had been visited during the visit
578 fun set_variable
(node
: AExpr, variable
: Variable, mtype
: nullable MType)
580 var flow
= node
.after_flow_context
583 flow
.set_var
(self, variable
, mtype
)
586 fun merge_types
(node
: ANode, col
: Array[nullable MType]): nullable MType
588 if col
.length
== 1 then return col
.first
590 if t1
== null then continue # return null
593 if t2
== null then continue # return null
594 if can_be_null
(t2
) and not can_be_null
(t1
) then
597 if not is_subtype
(t2
, t1
) then found
= false
600 #print "merge {col.join(" ")} -> {t1}"
604 #self.modelbuilder.warning(node, "Type Error: {col.length} conflicting types: <{col.join(", ")}>")
609 # Mapping between parameters and arguments in a call.
611 # Parameters and arguments are not stored in the class but referenced by their position (starting from 0)
613 # The point of this class is to help engine and other things to map arguments in the AST to parameters of the model.
615 # Associate a parameter to an argument
616 var map
= new ArrayMap[Int, Int]
619 # A specific method call site with its associated informations.
623 # The associated location of the callsite
624 var location
: Location
626 # The static type of the receiver (possibly unresolved)
629 # The module where the callsite is present
632 # The anchor to use with `recv` or `msignature`
633 var anchor
: nullable MClassType
635 # Is the receiver self?
636 # If "for_self", virtual types of the signature are kept
637 # If "not_for_self", virtual type are erased
638 var recv_is_self
: Bool
640 # The designated method
641 var mproperty
: MMethod
643 # The statically designated method definition
644 # The most specif one, it is.
645 var mpropdef
: MMethodDef
647 # The resolved signature for the receiver
648 var msignature
: MSignature
650 # Is a implicit cast required on erasure typing policy?
651 var erasure_cast
: Bool
653 # The mapping used on the call to associate arguments to parameters
654 # If null then no specific association is required.
655 var signaturemap
: nullable SignatureMap = null
657 private fun check_signature
(v
: TypeVisitor, node
: ANode, args
: Array[AExpr]): Bool
659 var map
= v
.check_signature
(node
, args
, self.mproperty
, self.msignature
)
661 if map
== null then is_broken
= true
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
853 # It indicates the number of arguments collected as a vararg.
855 # When 0, the argument is used as is, without transformation.
856 # When 1, the argument is transformed into an singleton array.
857 # Above 1, the arguments and the next ones are transformed into a common array.
859 # This attribute is meaning less on expressions not used as attributes.
860 var vararg_decl
: Int = 0
863 redef class ABlockExpr
864 redef fun accept_typing
(v
)
866 for e
in self.n_expr
do v
.visit_stmt
(e
)
870 # The type of a blockexpr is the one of the last expression (or null if empty)
873 if self.n_expr
.is_empty
then return null
874 return self.n_expr
.last
.mtype
878 redef class AVardeclExpr
879 redef fun accept_typing
(v
)
881 var variable
= self.variable
882 if variable
== null then return # Skip error
884 var ntype
= self.n_type
885 var mtype
: nullable MType
886 if ntype
== null then
889 mtype
= v
.resolve_mtype
(ntype
)
890 if mtype
== null then return # Skip error
893 var nexpr
= self.n_expr
894 if nexpr
!= null then
895 if mtype
!= null then
896 var etype
= v
.visit_expr_subtype
(nexpr
, mtype
)
897 if etype
== mtype
then
899 v
.modelbuilder
.advice
(ntype
, "useless-type", "Warning: useless type definition for variable `{variable.name}`")
902 mtype
= v
.visit_expr
(nexpr
)
903 if mtype
== null then return # Skip error
908 if mtype
== null or mtype
isa MNullType then
909 var objclass
= v
.get_mclass
(self, "Object")
910 if objclass
== null then return # skip error
911 decltype
= objclass
.mclass_type
.as_nullable
912 if mtype
== null then mtype
= decltype
915 variable
.declared_type
= decltype
916 v
.set_variable
(self, variable
, mtype
)
918 #debug("var {variable}: {mtype}")
926 redef fun its_variable
do return self.variable
927 redef fun accept_typing
(v
)
929 var variable
= self.variable
930 if variable
== null then return # Skip error
932 var mtype
= v
.get_variable
(self, variable
)
933 if mtype
!= null then
934 #debug("{variable} is {mtype}")
936 #debug("{variable} is untyped")
943 redef class AVarAssignExpr
944 redef fun accept_typing
(v
)
946 var variable
= self.variable
947 assert variable
!= null
949 var mtype
= v
.visit_expr_subtype
(n_value
, variable
.declared_type
)
951 v
.set_variable
(self, variable
, mtype
)
957 redef class AReassignFormExpr
958 # The method designed by the reassign operator.
959 var reassign_callsite
: nullable CallSite
961 var read_type
: nullable MType = null
963 # Determine the `reassign_property`
964 # `readtype` is the type of the reading of the left value.
965 # `writetype` is the type of the writing of the left value.
966 # (Because of `ACallReassignExpr`, both can be different.
967 # Return the static type of the value to store.
968 private fun resolve_reassignment
(v
: TypeVisitor, readtype
, writetype
: MType): nullable MType
970 var reassign_name
= self.n_assign_op
.operator
972 self.read_type
= readtype
974 var callsite
= v
.get_method
(self.n_assign_op
, readtype
, reassign_name
, false)
975 if callsite
== null then return null # Skip error
976 self.reassign_callsite
= callsite
978 var msignature
= callsite
.msignature
979 var rettype
= msignature
.return_mtype
980 assert msignature
.arity
== 1 and rettype
!= null
982 var value_type
= v
.visit_expr_subtype
(self.n_value
, msignature
.mparameters
.first
.mtype
)
983 if value_type
== null then return null # Skip error
985 v
.check_subtype
(self, rettype
, writetype
, false)
990 redef class AVarReassignExpr
991 redef fun accept_typing
(v
)
993 var variable
= self.variable
994 assert variable
!= null
996 var readtype
= v
.get_variable
(self, variable
)
997 if readtype
== null then return
1001 var writetype
= variable
.declared_type
1002 if writetype
== null then return
1004 var rettype
= self.resolve_reassignment
(v
, readtype
, writetype
)
1006 v
.set_variable
(self, variable
, rettype
)
1008 self.is_typed
= rettype
!= null
1013 redef class AContinueExpr
1014 redef fun accept_typing
(v
)
1016 var nexpr
= self.n_expr
1017 if nexpr
!= null then
1020 self.is_typed
= true
1024 redef class ABreakExpr
1025 redef fun accept_typing
(v
)
1027 var nexpr
= self.n_expr
1028 if nexpr
!= null then
1031 self.is_typed
= true
1035 redef class AReturnExpr
1036 redef fun accept_typing
(v
)
1038 var nexpr
= self.n_expr
1040 var mpropdef
= v
.mpropdef
1041 if mpropdef
isa MMethodDef then
1042 ret_type
= mpropdef
.msignature
.return_mtype
1043 else if mpropdef
isa MAttributeDef then
1044 ret_type
= mpropdef
.static_mtype
1048 if nexpr
!= null then
1049 if ret_type
!= null then
1050 v
.visit_expr_subtype
(nexpr
, ret_type
)
1053 v
.error
(nexpr
, "Error: `return` with value in a procedure.")
1056 else if ret_type
!= null then
1057 v
.error
(self, "Error: `return` without value in a function.")
1060 self.is_typed
= true
1064 redef class AAbortExpr
1065 redef fun accept_typing
(v
)
1067 self.is_typed
= true
1072 redef fun accept_typing
(v
)
1074 v
.visit_expr_bool
(n_expr
)
1076 v
.visit_stmt
(n_then
)
1077 v
.visit_stmt
(n_else
)
1079 self.is_typed
= true
1081 if n_then
!= null and n_else
== null then
1082 self.mtype
= n_then
.mtype
1087 redef class AIfexprExpr
1088 redef fun accept_typing
(v
)
1090 v
.visit_expr_bool
(n_expr
)
1092 var t1
= v
.visit_expr
(n_then
)
1093 var t2
= v
.visit_expr
(n_else
)
1095 if t1
== null or t2
== null then
1099 var t
= v
.merge_types
(self, [t1
, t2
])
1101 v
.error
(self, "Type Error: ambiguous type `{t1}` vs `{t2}`.")
1108 redef fun accept_typing
(v
)
1110 v
.visit_stmt
(n_block
)
1111 self.is_typed
= true
1115 redef class AWhileExpr
1116 redef fun accept_typing
(v
)
1119 v
.visit_expr_bool
(n_expr
)
1120 v
.visit_stmt
(n_block
)
1121 self.is_typed
= true
1125 redef class ALoopExpr
1126 redef fun accept_typing
(v
)
1129 v
.visit_stmt
(n_block
)
1130 self.is_typed
= true
1134 redef class AForExpr
1135 redef fun accept_typing
(v
)
1139 for g
in n_groups
do
1140 var mtype
= v
.visit_expr
(g
.n_expr
)
1141 if mtype
== null then return
1142 g
.do_type_iterator
(v
, mtype
)
1143 if g
.is_broken
then is_broken
= true
1146 v
.visit_stmt
(n_block
)
1148 self.mtype
= n_block
.mtype
1149 self.is_typed
= true
1153 redef class AForGroup
1154 var coltype
: nullable MClassType
1156 var method_iterator
: nullable CallSite
1157 var method_is_ok
: nullable CallSite
1158 var method_item
: nullable CallSite
1159 var method_next
: nullable CallSite
1160 var method_key
: nullable CallSite
1161 var method_finish
: nullable CallSite
1163 var method_lt
: nullable CallSite
1164 var method_successor
: nullable CallSite
1166 private fun do_type_iterator
(v
: TypeVisitor, mtype
: MType)
1168 if mtype
isa MNullType then
1169 v
.error
(self, "Type Error: `for` cannot iterate over `null`.")
1174 var objcla
= v
.get_mclass
(self, "Object")
1175 if objcla
== null then return
1177 # check iterator method
1178 var itdef
= v
.get_method
(self, mtype
, "iterator", n_expr
isa ASelfExpr)
1179 if itdef
== null then
1180 v
.error
(self, "Type Error: `for` expects a type providing an `iterator` method, got `{mtype}`.")
1183 self.method_iterator
= itdef
1185 # check that iterator return something
1186 var ittype
= itdef
.msignature
.return_mtype
1187 if ittype
== null then
1188 v
.error
(self, "Type Error: `for` expects the method `iterator` to return an `Iterator` or `MapIterator` type.")
1193 var colit_cla
= v
.try_get_mclass
(self, "Iterator")
1194 var mapit_cla
= v
.try_get_mclass
(self, "MapIterator")
1198 if colit_cla
!= null and v
.is_subtype
(ittype
, colit_cla
.get_mtype
([objcla
.mclass_type
.as_nullable
])) then
1200 var coltype
= ittype
.supertype_to
(v
.mmodule
, v
.anchor
, colit_cla
)
1201 var variables
= self.variables
1202 if variables
.length
!= 1 then
1203 v
.error
(self, "Type Error: `for` expects only one variable when using `Iterator`.")
1205 variables
.first
.declared_type
= coltype
.arguments
.first
1210 if mapit_cla
!= null and v
.is_subtype
(ittype
, mapit_cla
.get_mtype
([objcla
.mclass_type
.as_nullable
, objcla
.mclass_type
.as_nullable
])) then
1212 var coltype
= ittype
.supertype_to
(v
.mmodule
, v
.anchor
, mapit_cla
)
1213 var variables
= self.variables
1214 if variables
.length
!= 2 then
1215 v
.error
(self, "Type Error: `for` expects two variables when using `MapIterator`.")
1217 variables
[0].declared_type
= coltype
.arguments
[0]
1218 variables
[1].declared_type
= coltype
.arguments
[1]
1223 if not is_col
and not is_map
then
1224 v
.error
(self, "Type Error: `for` expects the method `iterator` to return an `Iterator` or `MapIterator` type.")
1228 # anchor formal and virtual types
1229 if mtype
.need_anchor
then mtype
= v
.anchor_to
(mtype
)
1231 mtype
= mtype
.undecorate
1232 self.coltype
= mtype
.as(MClassType)
1234 # get methods is_ok, next, item
1235 var ikdef
= v
.get_method
(self, ittype
, "is_ok", false)
1236 if ikdef
== null then
1237 v
.error
(self, "Type Error: `for` expects a method `is_ok` in type `{ittype}`.")
1240 self.method_is_ok
= ikdef
1242 var itemdef
= v
.get_method
(self, ittype
, "item", false)
1243 if itemdef
== null then
1244 v
.error
(self, "Type Error: `for` expects a method `item` in type `{ittype}`.")
1247 self.method_item
= itemdef
1249 var nextdef
= v
.get_method
(self, ittype
, "next", false)
1250 if nextdef
== null then
1251 v
.error
(self, "Type Error: `for` expects a method `next` in type {ittype}.")
1254 self.method_next
= nextdef
1256 self.method_finish
= v
.try_get_method
(self, ittype
, "finish", false)
1259 var keydef
= v
.get_method
(self, ittype
, "key", false)
1260 if keydef
== null then
1261 v
.error
(self, "Type Error: `for` expects a method `key` in type `{ittype}`.")
1264 self.method_key
= keydef
1267 if self.variables
.length
== 1 and n_expr
isa ARangeExpr then
1268 var variable
= variables
.first
1269 var vtype
= variable
.declared_type
.as(not null)
1271 if n_expr
isa AOrangeExpr then
1272 self.method_lt
= v
.get_method
(self, vtype
, "<", false)
1274 self.method_lt
= v
.get_method
(self, vtype
, "<=", false)
1277 self.method_successor
= v
.get_method
(self, vtype
, "successor", false)
1282 redef class AWithExpr
1283 var method_start
: nullable CallSite
1284 var method_finish
: nullable CallSite
1286 redef fun accept_typing
(v
: TypeVisitor)
1288 var mtype
= v
.visit_expr
(n_expr
)
1289 if mtype
== null then return
1291 method_start
= v
.get_method
(self, mtype
, "start", n_expr
isa ASelfExpr)
1292 method_finish
= v
.get_method
(self, mtype
, "finish", n_expr
isa ASelfExpr)
1294 v
.visit_stmt
(n_block
)
1295 self.mtype
= n_block
.mtype
1296 self.is_typed
= true
1300 redef class AAssertExpr
1301 redef fun accept_typing
(v
)
1303 v
.visit_expr_bool
(n_expr
)
1305 v
.visit_stmt
(n_else
)
1306 self.is_typed
= true
1311 redef fun accept_typing
(v
)
1313 v
.visit_expr_bool
(n_expr
)
1314 v
.visit_expr_bool
(n_expr2
)
1315 self.mtype
= v
.type_bool
(self)
1319 redef class AImpliesExpr
1320 redef fun accept_typing
(v
)
1322 v
.visit_expr_bool
(n_expr
)
1323 v
.visit_expr_bool
(n_expr2
)
1324 self.mtype
= v
.type_bool
(self)
1328 redef class AAndExpr
1329 redef fun accept_typing
(v
)
1331 v
.visit_expr_bool
(n_expr
)
1332 v
.visit_expr_bool
(n_expr2
)
1333 self.mtype
= v
.type_bool
(self)
1338 redef class ANotExpr
1339 redef fun accept_typing
(v
)
1341 v
.visit_expr_bool
(n_expr
)
1342 self.mtype
= v
.type_bool
(self)
1346 redef class AOrElseExpr
1347 redef fun accept_typing
(v
)
1349 var t1
= v
.visit_expr
(n_expr
)
1350 var t2
= v
.visit_expr
(n_expr2
)
1352 if t1
== null or t2
== null then
1356 if t1
isa MNullType then
1359 else if v
.can_be_null
(t1
) then
1363 var t
= v
.merge_types
(self, [t1
, t2
])
1365 var c
= v
.get_mclass
(self, "Object")
1366 if c
== null then return # forward error
1368 if v
.can_be_null
(t2
) then
1371 #v.error(self, "Type Error: ambiguous type {t1} vs {t2}")
1376 redef fun accept_post_typing
(v
)
1378 var t1
= n_expr
.mtype
1382 v
.check_can_be_null
(n_expr
, t1
)
1387 redef class ATrueExpr
1388 redef fun accept_typing
(v
)
1390 self.mtype
= v
.type_bool
(self)
1394 redef class AFalseExpr
1395 redef fun accept_typing
(v
)
1397 self.mtype
= v
.type_bool
(self)
1401 redef class AIntegerExpr
1402 redef fun accept_typing
(v
)
1404 var mclass
: nullable MClass = null
1405 if value
isa Byte then
1406 mclass
= v
.get_mclass
(self, "Byte")
1407 else if value
isa Int then
1408 mclass
= v
.get_mclass
(self, "Int")
1409 else if value
isa Int8 then
1410 mclass
= v
.get_mclass
(self, "Int8")
1411 else if value
isa Int16 then
1412 mclass
= v
.get_mclass
(self, "Int16")
1413 else if value
isa UInt16 then
1414 mclass
= v
.get_mclass
(self, "UInt16")
1415 else if value
isa Int32 then
1416 mclass
= v
.get_mclass
(self, "Int32")
1417 else if value
isa UInt32 then
1418 mclass
= v
.get_mclass
(self, "UInt32")
1420 if mclass
== null then return # Forward error
1421 self.mtype
= mclass
.mclass_type
1425 redef class AFloatExpr
1426 redef fun accept_typing
(v
)
1428 var mclass
= v
.get_mclass
(self, "Float")
1429 if mclass
== null then return # Forward error
1430 self.mtype
= mclass
.mclass_type
1434 redef class ACharExpr
1435 redef fun accept_typing
(v
)
1437 var mclass
= v
.get_mclass
(self, "Char")
1438 if mclass
== null then return # Forward error
1439 self.mtype
= mclass
.mclass_type
1443 redef class AStringFormExpr
1444 redef fun accept_typing
(v
)
1446 var mclass
= v
.get_mclass
(self, "String")
1447 if mclass
== null then return # Forward error
1448 self.mtype
= mclass
.mclass_type
1452 redef class ASuperstringExpr
1453 redef fun accept_typing
(v
)
1455 var mclass
= v
.get_mclass
(self, "String")
1456 if mclass
== null then return # Forward error
1457 self.mtype
= mclass
.mclass_type
1458 var objclass
= v
.get_mclass
(self, "Object")
1459 if objclass
== null then return # Forward error
1460 var objtype
= objclass
.mclass_type
1461 for nexpr
in self.n_exprs
do
1462 v
.visit_expr_subtype
(nexpr
, objtype
)
1467 redef class AArrayExpr
1468 # The `with_capacity` method on Array
1469 var with_capacity_callsite
: nullable CallSite
1471 # The `push` method on arrays
1472 var push_callsite
: nullable CallSite
1474 # The element of each type
1475 var element_mtype
: nullable MType
1477 # Set that `self` is a part of comprehension array `na`
1478 # If `self` is a `for`, or a `if`, then `set_comprehension` is recursively applied.
1479 private fun set_comprehension
(n
: nullable AExpr)
1483 else if n
isa AForExpr then
1484 set_comprehension
(n
.n_block
)
1485 else if n
isa AIfExpr then
1486 set_comprehension
(n
.n_then
)
1487 set_comprehension
(n
.n_else
)
1490 n
.comprehension
= self
1493 redef fun accept_typing
(v
)
1495 var mtype
: nullable MType = null
1496 var ntype
= self.n_type
1497 if ntype
!= null then
1498 mtype
= v
.resolve_mtype
(ntype
)
1499 if mtype
== null then return # Skip error
1501 var mtypes
= new Array[nullable MType]
1503 for e
in self.n_exprs
do
1504 var t
= v
.visit_expr
(e
)
1508 set_comprehension
(e
)
1509 if mtype
!= null then
1510 if v
.check_subtype
(e
, t
, mtype
, false) == null then return # Forward error
1511 if t
== mtype
then useless
= true
1516 if mtype
== null then
1517 # Ensure monotony for type adaptation on loops
1518 if self.element_mtype
!= null then mtypes
.add
self.element_mtype
1519 mtype
= v
.merge_types
(self, mtypes
)
1521 if mtype
== null or mtype
isa MNullType then
1522 v
.error
(self, "Type Error: ambiguous array type {mtypes.join(" ")}")
1526 assert ntype
!= null
1527 v
.modelbuilder
.warning
(ntype
, "useless-type", "Warning: useless type declaration `{mtype}` in literal Array since it can be inferred from the elements type.")
1530 self.element_mtype
= mtype
1532 var mclass
= v
.get_mclass
(self, "Array")
1533 if mclass
== null then return # Forward error
1534 var array_mtype
= mclass
.get_mtype
([mtype
])
1536 with_capacity_callsite
= v
.get_method
(self, array_mtype
, "with_capacity", false)
1537 push_callsite
= v
.get_method
(self, array_mtype
, "push", false)
1539 self.mtype
= array_mtype
1543 redef class ARangeExpr
1544 var init_callsite
: nullable CallSite
1546 redef fun accept_typing
(v
)
1548 var discrete_class
= v
.get_mclass
(self, "Discrete")
1549 if discrete_class
== null then return # Forward error
1550 var discrete_type
= discrete_class
.intro
.bound_mtype
1551 var t1
= v
.visit_expr_subtype
(self.n_expr
, discrete_type
)
1552 var t2
= v
.visit_expr_subtype
(self.n_expr2
, discrete_type
)
1553 if t1
== null or t2
== null then return
1554 var mclass
= v
.get_mclass
(self, "Range")
1555 if mclass
== null then return # Forward error
1557 if v
.is_subtype
(t1
, t2
) then
1558 mtype
= mclass
.get_mtype
([t2
])
1559 else if v
.is_subtype
(t2
, t1
) then
1560 mtype
= mclass
.get_mtype
([t1
])
1562 v
.error
(self, "Type Error: cannot create range: `{t1}` vs `{t2}`.")
1568 # get the constructor
1570 if self isa ACrangeExpr then
1571 callsite
= v
.get_method
(self, mtype
, "init", false)
1572 else if self isa AOrangeExpr then
1573 callsite
= v
.get_method
(self, mtype
, "without_last", false)
1577 init_callsite
= callsite
1581 redef class ANullExpr
1582 redef fun accept_typing
(v
)
1584 self.mtype
= v
.mmodule
.model
.null_type
1588 redef class AIsaExpr
1589 # The static type to cast to.
1590 # (different from the static type of the expression that is `Bool`).
1591 var cast_type
: nullable MType
1592 redef fun accept_typing
(v
)
1594 v
.visit_expr
(n_expr
)
1596 var mtype
= v
.resolve_mtype
(n_type
)
1598 self.cast_type
= mtype
1600 var variable
= self.n_expr
.its_variable
1601 if variable
!= null then
1602 #var orig = self.n_expr.mtype
1603 #var from = if orig != null then orig.to_s else "invalid"
1604 #var to = if mtype != null then mtype.to_s else "invalid"
1605 #debug("adapt {variable}: {from} -> {to}")
1606 self.after_flow_context
.when_true
.set_var
(v
, variable
, mtype
)
1609 self.mtype
= v
.type_bool
(self)
1612 redef fun accept_post_typing
(v
)
1614 v
.check_expr_cast
(self, self.n_expr
, self.n_type
)
1618 redef class AAsCastExpr
1619 redef fun accept_typing
(v
)
1621 v
.visit_expr
(n_expr
)
1623 self.mtype
= v
.resolve_mtype
(n_type
)
1626 redef fun accept_post_typing
(v
)
1628 v
.check_expr_cast
(self, self.n_expr
, self.n_type
)
1632 redef class AAsNotnullExpr
1633 redef fun accept_typing
(v
)
1635 var mtype
= v
.visit_expr
(self.n_expr
)
1636 if mtype
== null then return # Forward error
1638 if mtype
isa MNullType then
1639 v
.error
(self, "Type Error: `as(not null)` on `null`.")
1643 if v
.can_be_null
(mtype
) then
1644 mtype
= mtype
.as_notnull
1650 redef fun accept_post_typing
(v
)
1652 var mtype
= n_expr
.mtype
1653 if mtype
== null then return
1654 v
.check_can_be_null
(n_expr
, mtype
)
1658 redef class AParExpr
1659 redef fun accept_typing
(v
)
1661 self.mtype
= v
.visit_expr
(self.n_expr
)
1665 redef class AOnceExpr
1666 redef fun accept_typing
(v
)
1668 self.mtype
= v
.visit_expr
(self.n_expr
)
1672 redef class ASelfExpr
1673 redef var its_variable
: nullable Variable
1674 redef fun accept_typing
(v
)
1676 if v
.is_toplevel_context
and not self isa AImplicitSelfExpr then
1677 v
.error
(self, "Error: `self` cannot be used in top-level method.")
1679 var variable
= v
.selfvariable
1680 self.its_variable
= variable
1681 self.mtype
= v
.get_variable
(self, variable
)
1685 redef class AImplicitSelfExpr
1686 # Is the implicit receiver `sys`?
1688 # By default, the implicit receiver is `self`.
1689 # But when there is not method for `self`, `sys` is used as a fall-back.
1690 # Is this case this flag is set to `true`.
1694 ## MESSAGE SENDING AND PROPERTY
1696 redef class ASendExpr
1697 # The property invoked by the send.
1698 var callsite
: nullable CallSite
1700 redef fun accept_typing
(v
)
1702 var nrecv
= self.n_expr
1703 var recvtype
= v
.visit_expr
(nrecv
)
1704 var name
= self.property_name
1705 var node
= self.property_node
1707 if recvtype
== null then return # Forward error
1710 var unsafe_type
= v
.anchor_to
(recvtype
)
1711 var mproperty
= v
.try_get_mproperty_by_name2
(node
, unsafe_type
, name
)
1712 if mproperty
== null and nrecv
isa AImplicitSelfExpr then
1713 # Special fall-back search in `sys` when noting found in the implicit receiver.
1714 var sysclass
= v
.try_get_mclass
(node
, "Sys")
1715 if sysclass
!= null then
1716 var systype
= sysclass
.mclass_type
1717 mproperty
= v
.try_get_mproperty_by_name2
(node
, systype
, name
)
1718 if mproperty
!= null then
1719 callsite
= v
.get_method
(node
, systype
, name
, false)
1720 if callsite
== null then return # Forward error
1721 # Update information, we are looking at `sys` now, not `self`
1723 nrecv
.its_variable
= null
1724 nrecv
.mtype
= systype
1729 if callsite
== null then
1730 # If still nothing, just exit
1731 callsite
= v
.get_method
(node
, recvtype
, name
, nrecv
isa ASelfExpr)
1732 if callsite
== null then return
1735 self.callsite
= callsite
1736 var msignature
= callsite
.msignature
1738 var args
= compute_raw_arguments
1740 callsite
.check_signature
(v
, node
, args
)
1742 if callsite
.mproperty
.is_init
then
1743 var vmpropdef
= v
.mpropdef
1744 if not (vmpropdef
isa MMethodDef and vmpropdef
.mproperty
.is_init
) then
1745 v
.error
(node
, "Error: an `init` can only be called from another `init`.")
1747 if vmpropdef
isa MMethodDef and vmpropdef
.mproperty
.is_root_init
and not callsite
.mproperty
.is_root_init
then
1748 v
.error
(node
, "Error: `{vmpropdef}` cannot call a factory `{callsite.mproperty}`.")
1752 var ret
= msignature
.return_mtype
1756 self.is_typed
= true
1760 # The name of the property
1761 # Each subclass simply provide the correct name.
1762 private fun property_name
: String is abstract
1764 # The node identifying the name (id, operator, etc) for messages.
1766 # Is `self` by default
1767 private fun property_node
: ANode do return self
1769 # An array of all arguments (excluding self)
1770 fun raw_arguments
: Array[AExpr] do return compute_raw_arguments
1772 private fun compute_raw_arguments
: Array[AExpr] is abstract
1775 redef class ABinopExpr
1776 redef fun compute_raw_arguments
do return [n_expr2
]
1777 redef fun property_name
do return operator
1778 redef fun property_node
do return n_op
1781 redef class AEqFormExpr
1782 redef fun accept_typing
(v
)
1788 redef fun accept_post_typing
(v
)
1790 var mtype
= n_expr
.mtype
1791 var mtype2
= n_expr2
.mtype
1793 if mtype
== null or mtype2
== null then return
1795 if not mtype2
isa MNullType then return
1797 v
.check_can_be_null
(n_expr
, mtype
)
1801 redef class AUnaryopExpr
1802 redef fun property_name
do return "unary {operator}"
1803 redef fun compute_raw_arguments
do return new Array[AExpr]
1807 redef class ACallExpr
1808 redef fun property_name
do return n_qid
.n_id
.text
1809 redef fun property_node
do return n_qid
1810 redef fun compute_raw_arguments
do return n_args
.to_a
1813 redef class ACallAssignExpr
1814 redef fun property_name
do return n_qid
.n_id
.text
+ "="
1815 redef fun property_node
do return n_qid
1816 redef fun compute_raw_arguments
1818 var res
= n_args
.to_a
1824 redef class ABraExpr
1825 redef fun property_name
do return "[]"
1826 redef fun compute_raw_arguments
do return n_args
.to_a
1829 redef class ABraAssignExpr
1830 redef fun property_name
do return "[]="
1831 redef fun compute_raw_arguments
1833 var res
= n_args
.to_a
1839 redef class ASendReassignFormExpr
1840 # The property invoked for the writing
1841 var write_callsite
: nullable CallSite
1843 redef fun accept_typing
(v
)
1845 var recvtype
= v
.visit_expr
(self.n_expr
)
1846 var name
= self.property_name
1847 var node
= self.property_node
1849 if recvtype
== null then return # Forward error
1851 var for_self
= self.n_expr
isa ASelfExpr
1852 var callsite
= v
.get_method
(node
, recvtype
, name
, for_self
)
1854 if callsite
== null then return
1855 self.callsite
= callsite
1857 var args
= compute_raw_arguments
1859 callsite
.check_signature
(v
, node
, args
)
1861 var readtype
= callsite
.msignature
.return_mtype
1862 if readtype
== null then
1863 v
.error
(node
, "Error: `{name}` is not a function.")
1867 var wcallsite
= v
.get_method
(node
, recvtype
, name
+ "=", self.n_expr
isa ASelfExpr)
1868 if wcallsite
== null then return
1869 self.write_callsite
= wcallsite
1871 var wtype
= self.resolve_reassignment
(v
, readtype
, wcallsite
.msignature
.mparameters
.last
.mtype
)
1872 if wtype
== null then return
1874 args
= args
.to_a
# duplicate so raw_arguments keeps only the getter args
1875 args
.add
(self.n_value
)
1876 wcallsite
.check_signature
(v
, node
, args
)
1878 self.is_typed
= true
1882 redef class ACallReassignExpr
1883 redef fun property_name
do return n_qid
.n_id
.text
1884 redef fun property_node
do return n_qid
.n_id
1885 redef fun compute_raw_arguments
do return n_args
.to_a
1888 redef class ABraReassignExpr
1889 redef fun property_name
do return "[]"
1890 redef fun compute_raw_arguments
do return n_args
.to_a
1893 redef class AInitExpr
1894 redef fun property_name
do return "init"
1895 redef fun property_node
do return n_kwinit
1896 redef fun compute_raw_arguments
do return n_args
.to_a
1900 fun to_a
: Array[AExpr] do return self.n_exprs
.to_a
1905 redef class ASuperExpr
1906 # The method to call if the super is in fact a 'super init call'
1907 # Note: if the super is a normal call-next-method, then this attribute is null
1908 var callsite
: nullable CallSite
1910 # The method to call is the super is a standard `call-next-method` super-call
1911 # Note: if the super is a special super-init-call, then this attribute is null
1912 var mpropdef
: nullable MMethodDef
1914 redef fun accept_typing
(v
)
1916 var anchor
= v
.anchor
1917 assert anchor
!= null
1918 var recvtype
= v
.get_variable
(self, v
.selfvariable
)
1919 assert recvtype
!= null
1920 var mproperty
= v
.mpropdef
.mproperty
1921 if not mproperty
isa MMethod then
1922 v
.error
(self, "Error: `super` only usable in a `method`.")
1925 var superprops
= mproperty
.lookup_super_definitions
(v
.mmodule
, anchor
)
1926 if superprops
.length
== 0 then
1927 if mproperty
.is_init
and v
.mpropdef
.is_intro
then
1928 process_superinit
(v
)
1931 v
.error
(self, "Error: no super method to call for `{mproperty}`.")
1934 # FIXME: covariance of return type in linear extension?
1935 var superprop
= superprops
.first
1937 var msignature
= superprop
.msignature
.as(not null)
1938 msignature
= v
.resolve_for
(msignature
, recvtype
, true).as(MSignature)
1939 var args
= self.n_args
.to_a
1940 if args
.length
> 0 then
1941 signaturemap
= v
.check_signature
(self, args
, mproperty
, msignature
)
1943 self.mtype
= msignature
.return_mtype
1944 self.is_typed
= true
1945 v
.mpropdef
.has_supercall
= true
1946 mpropdef
= v
.mpropdef
.as(MMethodDef)
1949 # The mapping used on the call to associate arguments to parameters.
1950 # If null then no specific association is required.
1951 var signaturemap
: nullable SignatureMap
1953 private fun process_superinit
(v
: TypeVisitor)
1955 var anchor
= v
.anchor
1956 assert anchor
!= null
1957 var recvtype
= v
.get_variable
(self, v
.selfvariable
)
1958 assert recvtype
!= null
1959 var mpropdef
= v
.mpropdef
1960 assert mpropdef
isa MMethodDef
1961 var mproperty
= mpropdef
.mproperty
1962 var superprop
: nullable MMethodDef = null
1963 for msupertype
in mpropdef
.mclassdef
.supertypes
do
1964 msupertype
= msupertype
.anchor_to
(v
.mmodule
, anchor
)
1965 var errcount
= v
.modelbuilder
.toolcontext
.error_count
1966 var candidate
= v
.try_get_mproperty_by_name2
(self, msupertype
, mproperty
.name
).as(nullable MMethod)
1967 if candidate
== null then
1968 if v
.modelbuilder
.toolcontext
.error_count
> errcount
then return # Forward error
1969 continue # Try next super-class
1971 if superprop
!= null and candidate
.is_root_init
then
1974 if superprop
!= null and superprop
.mproperty
!= candidate
and not superprop
.mproperty
.is_root_init
then
1975 v
.error
(self, "Error: conflicting super constructor to call for `{mproperty}`: `{candidate.full_name}`, `{superprop.mproperty.full_name}`")
1978 var candidatedefs
= candidate
.lookup_definitions
(v
.mmodule
, anchor
)
1979 if superprop
!= null and superprop
.mproperty
== candidate
then
1980 if superprop
== candidatedefs
.first
then continue
1981 candidatedefs
.add
(superprop
)
1983 if candidatedefs
.length
> 1 then
1984 v
.error
(self, "Error: conflicting property definitions for property `{mproperty}` in `{recvtype}`: {candidatedefs.join(", ")}")
1987 superprop
= candidatedefs
.first
1989 if superprop
== null then
1990 v
.error
(self, "Error: no super method to call for `{mproperty}`.")
1994 var msignature
= superprop
.new_msignature
or else superprop
.msignature
.as(not null)
1995 msignature
= v
.resolve_for
(msignature
, recvtype
, true).as(MSignature)
1997 var callsite
= new CallSite(hot_location
, recvtype
, v
.mmodule
, v
.anchor
, true, superprop
.mproperty
, superprop
, msignature
, false)
1998 self.callsite
= callsite
2000 var args
= self.n_args
.to_a
2001 if args
.length
> 0 then
2002 callsite
.check_signature
(v
, self, args
)
2004 # Check there is at least enough parameters
2005 if mpropdef
.msignature
.arity
< msignature
.arity
then
2006 v
.error
(self, "Error: not enough implicit arguments to pass. Got `{mpropdef.msignature.arity}`, expected at least `{msignature.arity}`. Signature is `{msignature}`.")
2009 # Check that each needed parameter is conform
2011 for sp
in msignature
.mparameters
do
2012 var p
= mpropdef
.msignature
.mparameters
[i
]
2013 if not v
.is_subtype
(p
.mtype
, sp
.mtype
) then
2014 v
.error
(self, "Type Error: expected argument #{i} of type `{sp.mtype}`, got implicit argument `{p.name}` of type `{p.mtype}`. Signature is {msignature}")
2021 self.is_typed
= true
2027 redef class ANewExpr
2028 # The constructor invoked by the new.
2029 var callsite
: nullable CallSite
2031 # The designated type
2032 var recvtype
: nullable MClassType
2034 redef fun accept_typing
(v
)
2036 var recvtype
= v
.resolve_mtype
(self.n_type
)
2037 if recvtype
== null then return
2039 if not recvtype
isa MClassType then
2040 if recvtype
isa MNullableType then
2041 v
.error
(self, "Type Error: cannot instantiate the nullable type `{recvtype}`.")
2043 else if recvtype
isa MFormalType then
2044 v
.error
(self, "Type Error: cannot instantiate the formal type `{recvtype}`.")
2047 v
.error
(self, "Type Error: cannot instantiate the type `{recvtype}`.")
2052 self.recvtype
= recvtype
2053 var kind
= recvtype
.mclass
.kind
2056 var nqid
= self.n_qid
2058 if nqid
!= null then
2059 name
= nqid
.n_id
.text
2065 if name
== "intern" then
2066 if kind
!= concrete_kind
then
2067 v
.error
(self, "Type Error: cannot instantiate {kind} {recvtype}.")
2070 if n_args
.n_exprs
.not_empty
then
2071 v
.error
(n_args
, "Type Error: the intern constructor expects no arguments.")
2075 self.mtype
= recvtype
2079 var callsite
= v
.get_method
(node
, recvtype
, name
, false)
2080 if callsite
== null then return
2082 if not callsite
.mproperty
.is_new
then
2083 if kind
!= concrete_kind
then
2084 v
.error
(self, "Type Error: cannot instantiate {kind} `{recvtype}`.")
2087 self.mtype
= recvtype
2089 self.mtype
= callsite
.msignature
.return_mtype
2090 assert self.mtype
!= null
2093 self.callsite
= callsite
2095 if not callsite
.mproperty
.is_init_for
(recvtype
.mclass
) then
2096 v
.error
(self, "Error: `{name}` is not a constructor.")
2100 var args
= n_args
.to_a
2101 callsite
.check_signature
(v
, node
, args
)
2107 redef class AAttrFormExpr
2108 # The attribute accessed.
2109 var mproperty
: nullable MAttribute
2111 # The static type of the attribute.
2112 var attr_type
: nullable MType
2114 # Resolve the attribute accessed.
2115 private fun resolve_property
(v
: TypeVisitor)
2117 var recvtype
= v
.visit_expr
(self.n_expr
)
2118 if recvtype
== null then return # Skip error
2119 var node
= self.n_id
2120 var name
= node
.text
2121 if recvtype
isa MNullType then
2122 v
.error
(node
, "Error: attribute `{name}` access on `null`.")
2126 var unsafe_type
= v
.anchor_to
(recvtype
)
2127 var mproperty
= v
.try_get_mproperty_by_name2
(node
, unsafe_type
, name
)
2128 if mproperty
== null then
2129 v
.modelbuilder
.error
(node
, "Error: attribute `{name}` does not exist in `{recvtype}`.")
2132 assert mproperty
isa MAttribute
2133 self.mproperty
= mproperty
2135 var mpropdefs
= mproperty
.lookup_definitions
(v
.mmodule
, unsafe_type
)
2136 assert mpropdefs
.length
== 1
2137 var mpropdef
= mpropdefs
.first
2138 var attr_type
= mpropdef
.static_mtype
2139 if attr_type
== null then return # skip error
2140 attr_type
= v
.resolve_for
(attr_type
, recvtype
, self.n_expr
isa ASelfExpr)
2141 self.attr_type
= attr_type
2145 redef class AAttrExpr
2146 redef fun accept_typing
(v
)
2148 self.resolve_property
(v
)
2149 self.mtype
= self.attr_type
2154 redef class AAttrAssignExpr
2155 redef fun accept_typing
(v
)
2157 self.resolve_property
(v
)
2158 var mtype
= self.attr_type
2160 v
.visit_expr_subtype
(self.n_value
, mtype
)
2161 self.is_typed
= mtype
!= null
2165 redef class AAttrReassignExpr
2166 redef fun accept_typing
(v
)
2168 self.resolve_property
(v
)
2169 var mtype
= self.attr_type
2170 if mtype
== null then return # Skip error
2172 var rettype
= self.resolve_reassignment
(v
, mtype
, mtype
)
2174 self.is_typed
= rettype
!= null
2178 redef class AIssetAttrExpr
2179 redef fun accept_typing
(v
)
2181 self.resolve_property
(v
)
2182 var mtype
= self.attr_type
2183 if mtype
== null then return # Skip error
2185 var recvtype
= self.n_expr
.mtype
.as(not null)
2186 var bound
= v
.resolve_for
(mtype
, recvtype
, false)
2187 if bound
isa MNullableType then
2188 v
.error
(n_id
, "Type Error: `isset` on a nullable attribute.")
2190 self.mtype
= v
.type_bool
(self)
2194 redef class AVarargExpr
2195 redef fun accept_typing
(v
)
2197 # This kind of pseudo-expression can be only processed trough a signature
2198 # See `check_signature`
2199 # Other cases are a syntax error.
2200 v
.error
(self, "Syntax Error: unexpected `...`.")
2206 redef class ADebugTypeExpr
2207 redef fun accept_typing
(v
)
2209 var expr
= v
.visit_expr
(self.n_expr
)
2210 if expr
== null then return
2211 var unsafe
= v
.anchor_to
(expr
)
2212 var ntype
= self.n_type
2213 var mtype
= v
.resolve_mtype
(ntype
)
2214 if mtype
!= null and mtype
!= expr
then
2215 var umtype
= v
.anchor_to
(mtype
)
2216 v
.modelbuilder
.warning
(self, "debug", "Found type {expr} (-> {unsafe}), expected {mtype} (-> {umtype})")
2218 self.is_typed
= true