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
.hot_location
, 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.
626 # The associated location of the callsite
627 var location
: Location
629 # The static type of the receiver (possibly unresolved)
632 # The module where the callsite is present
635 # The anchor to use with `recv` or `msignature`
636 var anchor
: nullable MClassType
638 # Is the receiver self?
639 # If "for_self", virtual types of the signature are kept
640 # If "not_for_self", virtual type are erased
641 var recv_is_self
: Bool
643 # The designated method
644 var mproperty
: MMethod
646 # The statically designated method definition
647 # The most specif one, it is.
648 var mpropdef
: MMethodDef
650 # The resolved signature for the receiver
651 var msignature
: MSignature
653 # Is a implicit cast required on erasure typing policy?
654 var erasure_cast
: Bool
656 # The mapping used on the call to associate arguments to parameters
657 # If null then no specific association is required.
658 var signaturemap
: nullable SignatureMap = null
660 private fun check_signature
(v
: TypeVisitor, node
: ANode, args
: Array[AExpr]): Bool
662 var map
= v
.check_signature
(node
, args
, self.mproperty
, self.msignature
)
664 if map
== null then is_broken
= true
670 # The declared type of the variable
671 var declared_type
: nullable MType is writable
673 # Was the variable type-adapted?
674 # This is used to speedup type retrieval while it remains `false`
675 private var is_adapted
= false
678 redef class FlowContext
679 # Store changes of types because of type evolution
680 private var vars
= new HashMap[Variable, nullable MType]
682 # Adapt the variable to a static type
683 # Warning1: do not modify vars directly.
684 # Warning2: sub-flow may have cached a unadapted variable
685 private fun set_var
(v
: TypeVisitor, variable
: Variable, mtype
: nullable MType)
687 if variable
.declared_type
== mtype
and not variable
.is_adapted
then return
688 if vars
.has_key
(variable
) and vars
[variable
] == mtype
then return
689 self.vars
[variable
] = mtype
691 variable
.is_adapted
= true
692 #node.debug "set {variable} to {mtype or else "X"}"
695 # Look in the flow and previous flow and collect all first reachable type adaptation of a local variable
696 private fun collect_types
(variable
: Variable): Array[nullable MType]
698 #node.debug "flow for {variable}"
699 var res
= new Array[nullable MType]
702 var seen
= new HashSet[FlowContext]
703 while not todo
.is_empty
do
705 if f
.is_unreachable
then continue
706 if seen
.has
(f
) then continue
709 if f
.vars
.has_key
(variable
) then
710 # Found something. Collect it and do not process further on this path
711 res
.add f
.vars
[variable
]
712 #f.node.debug "process {variable}: got {f.vars[variable] or else "X"}"
714 todo
.add_all f
.previous
716 if f
.previous
.is_empty
then
717 # Root flowcontext mean a parameter or something related
718 res
.add variable
.declared_type
719 #f.node.debug "root process {variable}: got {variable.declared_type or else "X"}"
723 #self.node.debug "##### end flow for {variable}: {res.join(" ")}"
729 # The entry point of the whole typing analysis
730 fun do_typing
(modelbuilder
: ModelBuilder)
734 # The variable associated to the receiver (if any)
735 var selfvariable
: nullable Variable
738 redef class AMethPropdef
739 redef fun do_typing
(modelbuilder
: ModelBuilder)
741 var mpropdef
= self.mpropdef
742 if mpropdef
== null then return # skip error
744 var v
= new TypeVisitor(modelbuilder
, mpropdef
.mclassdef
.mmodule
, mpropdef
)
745 self.selfvariable
= v
.selfvariable
747 var mmethoddef
= self.mpropdef
.as(not null)
748 var msignature
= mmethoddef
.msignature
749 if msignature
== null then return # skip error
750 for i
in [0..msignature
.arity
[ do
751 var mtype
= msignature
.mparameters
[i
].mtype
752 if msignature
.vararg_rank
== i
then
753 var arrayclass
= v
.get_mclass
(self.n_signature
.n_params
[i
], "Array")
754 if arrayclass
== null then return # Skip error
755 mtype
= arrayclass
.get_mtype
([mtype
])
757 var variable
= self.n_signature
.n_params
[i
].variable
758 assert variable
!= null
759 variable
.declared_type
= mtype
762 var nblock
= self.n_block
763 if nblock
== null then return
768 if not v
.has_loop
or not v
.dirty
then break
771 var post_visitor
= new PostTypingVisitor(v
)
772 post_visitor
.enter_visit
(self)
774 if not nblock
.after_flow_context
.is_unreachable
and msignature
.return_mtype
!= null then
775 # We reach the end of the function without having a return, it is bad
776 v
.error
(self, "Error: reached end of function; expected `return` with a value.")
781 private class PostTypingVisitor
783 var type_visitor
: TypeVisitor
784 redef fun visit
(n
) do
786 n
.accept_post_typing
(type_visitor
)
787 if n
isa AExpr and n
.mtype
== null and not n
.is_typed
then
794 private fun accept_post_typing
(v
: TypeVisitor) do end
797 redef class AAttrPropdef
798 redef fun do_typing
(modelbuilder
: ModelBuilder)
800 if not has_value
then return
802 var mpropdef
= self.mreadpropdef
803 if mpropdef
== null or mpropdef
.msignature
== null then return # skip error
805 var v
= new TypeVisitor(modelbuilder
, mpropdef
.mclassdef
.mmodule
, mpropdef
)
806 self.selfvariable
= v
.selfvariable
808 var nexpr
= self.n_expr
809 if nexpr
!= null then
810 var mtype
= self.mtype
811 v
.visit_expr_subtype
(nexpr
, mtype
)
813 var nblock
= self.n_block
814 if nblock
!= null then
816 if not nblock
.after_flow_context
.is_unreachable
then
817 # We reach the end of the init without having a return, it is bad
818 v
.error
(self, "Error: reached end of block; expected `return`.")
827 # The static type of the expression.
828 # null if self is a statement or in case of error
829 var mtype
: nullable MType = null
831 # Is the statement correctly typed?
832 # Used to distinguish errors and statements when `mtype == null`
833 var is_typed
: Bool = false
835 # If required, the following implicit cast `.as(XXX)`
836 # Such a cast may by required after evaluating the expression when
837 # a unsafe operation is detected (silently accepted by the Nit language).
838 # The attribute is computed by `check_subtype`
839 var implicit_cast_to
: nullable MType = null
841 # Return the variable read (if any)
842 # Used to perform adaptive typing
843 fun its_variable
: nullable Variable do return null
845 private fun accept_typing
(v
: TypeVisitor)
847 v
.error
(self, "no implemented accept_typing for {self.class_name}")
850 # Is non-null if `self` is a leaf of a comprehension array construction.
851 # In this case, the enclosing literal array node is designated.
852 # The result of the evaluation of `self` must be
853 # stored inside the designated array (there is an implicit `push`)
854 var comprehension
: nullable AArrayExpr = null
857 redef class ABlockExpr
858 redef fun accept_typing
(v
)
860 for e
in self.n_expr
do v
.visit_stmt
(e
)
864 # The type of a blockexpr is the one of the last expression (or null if empty)
867 if self.n_expr
.is_empty
then return null
868 return self.n_expr
.last
.mtype
872 redef class AVardeclExpr
873 redef fun accept_typing
(v
)
875 var variable
= self.variable
876 if variable
== null then return # Skip error
878 var ntype
= self.n_type
879 var mtype
: nullable MType
880 if ntype
== null then
883 mtype
= v
.resolve_mtype
(ntype
)
884 if mtype
== null then return # Skip error
887 var nexpr
= self.n_expr
888 if nexpr
!= null then
889 if mtype
!= null then
890 var etype
= v
.visit_expr_subtype
(nexpr
, mtype
)
891 if etype
== mtype
then
893 v
.modelbuilder
.advice
(ntype
, "useless-type", "Warning: useless type definition for variable `{variable.name}`")
896 mtype
= v
.visit_expr
(nexpr
)
897 if mtype
== null then return # Skip error
902 if mtype
== null or mtype
isa MNullType then
903 var objclass
= v
.get_mclass
(self, "Object")
904 if objclass
== null then return # skip error
905 decltype
= objclass
.mclass_type
.as_nullable
906 if mtype
== null then mtype
= decltype
909 variable
.declared_type
= decltype
910 v
.set_variable
(self, variable
, mtype
)
912 #debug("var {variable}: {mtype}")
920 redef fun its_variable
do return self.variable
921 redef fun accept_typing
(v
)
923 var variable
= self.variable
924 if variable
== null then return # Skip error
926 var mtype
= v
.get_variable
(self, variable
)
927 if mtype
!= null then
928 #debug("{variable} is {mtype}")
930 #debug("{variable} is untyped")
937 redef class AVarAssignExpr
938 redef fun accept_typing
(v
)
940 var variable
= self.variable
941 assert variable
!= null
943 var mtype
= v
.visit_expr_subtype
(n_value
, variable
.declared_type
)
945 v
.set_variable
(self, variable
, mtype
)
951 redef class AReassignFormExpr
952 # The method designed by the reassign operator.
953 var reassign_callsite
: nullable CallSite
955 var read_type
: nullable MType = null
957 # Determine the `reassign_property`
958 # `readtype` is the type of the reading of the left value.
959 # `writetype` is the type of the writing of the left value.
960 # (Because of `ACallReassignExpr`, both can be different.
961 # Return the static type of the value to store.
962 private fun resolve_reassignment
(v
: TypeVisitor, readtype
, writetype
: MType): nullable MType
964 var reassign_name
= self.n_assign_op
.operator
966 self.read_type
= readtype
968 var callsite
= v
.get_method
(self.n_assign_op
, readtype
, reassign_name
, false)
969 if callsite
== null then return null # Skip error
970 self.reassign_callsite
= callsite
972 var msignature
= callsite
.msignature
973 var rettype
= msignature
.return_mtype
974 assert msignature
.arity
== 1 and rettype
!= null
976 var value_type
= v
.visit_expr_subtype
(self.n_value
, msignature
.mparameters
.first
.mtype
)
977 if value_type
== null then return null # Skip error
979 v
.check_subtype
(self, rettype
, writetype
, false)
984 redef class AVarReassignExpr
985 redef fun accept_typing
(v
)
987 var variable
= self.variable
988 assert variable
!= null
990 var readtype
= v
.get_variable
(self, variable
)
991 if readtype
== null then return
995 var writetype
= variable
.declared_type
996 if writetype
== null then return
998 var rettype
= self.resolve_reassignment
(v
, readtype
, writetype
)
1000 v
.set_variable
(self, variable
, rettype
)
1002 self.is_typed
= rettype
!= null
1007 redef class AContinueExpr
1008 redef fun accept_typing
(v
)
1010 var nexpr
= self.n_expr
1011 if nexpr
!= null then
1014 self.is_typed
= true
1018 redef class ABreakExpr
1019 redef fun accept_typing
(v
)
1021 var nexpr
= self.n_expr
1022 if nexpr
!= null then
1025 self.is_typed
= true
1029 redef class AReturnExpr
1030 redef fun accept_typing
(v
)
1032 var nexpr
= self.n_expr
1034 var mpropdef
= v
.mpropdef
1035 if mpropdef
isa MMethodDef then
1036 ret_type
= mpropdef
.msignature
.return_mtype
1037 else if mpropdef
isa MAttributeDef then
1038 ret_type
= mpropdef
.static_mtype
1042 if nexpr
!= null then
1043 if ret_type
!= null then
1044 v
.visit_expr_subtype
(nexpr
, ret_type
)
1047 v
.error
(nexpr
, "Error: `return` with value in a procedure.")
1050 else if ret_type
!= null then
1051 v
.error
(self, "Error: `return` without value in a function.")
1054 self.is_typed
= true
1058 redef class AAbortExpr
1059 redef fun accept_typing
(v
)
1061 self.is_typed
= true
1066 redef fun accept_typing
(v
)
1068 v
.visit_expr_bool
(n_expr
)
1070 v
.visit_stmt
(n_then
)
1071 v
.visit_stmt
(n_else
)
1073 self.is_typed
= true
1075 if n_then
!= null and n_else
== null then
1076 self.mtype
= n_then
.mtype
1081 redef class AIfexprExpr
1082 redef fun accept_typing
(v
)
1084 v
.visit_expr_bool
(n_expr
)
1086 var t1
= v
.visit_expr
(n_then
)
1087 var t2
= v
.visit_expr
(n_else
)
1089 if t1
== null or t2
== null then
1093 var t
= v
.merge_types
(self, [t1
, t2
])
1095 v
.error
(self, "Type Error: ambiguous type `{t1}` vs `{t2}`.")
1102 redef fun accept_typing
(v
)
1104 v
.visit_stmt
(n_block
)
1105 self.is_typed
= true
1109 redef class AWhileExpr
1110 redef fun accept_typing
(v
)
1113 v
.visit_expr_bool
(n_expr
)
1114 v
.visit_stmt
(n_block
)
1115 self.is_typed
= true
1119 redef class ALoopExpr
1120 redef fun accept_typing
(v
)
1123 v
.visit_stmt
(n_block
)
1124 self.is_typed
= true
1128 redef class AForExpr
1129 redef fun accept_typing
(v
)
1133 for g
in n_groups
do
1134 var mtype
= v
.visit_expr
(g
.n_expr
)
1135 if mtype
== null then return
1136 g
.do_type_iterator
(v
, mtype
)
1139 v
.visit_stmt
(n_block
)
1141 self.mtype
= n_block
.mtype
1142 self.is_typed
= true
1146 redef class AForGroup
1147 var coltype
: nullable MClassType
1149 var method_iterator
: nullable CallSite
1150 var method_is_ok
: nullable CallSite
1151 var method_item
: nullable CallSite
1152 var method_next
: nullable CallSite
1153 var method_key
: nullable CallSite
1154 var method_finish
: nullable CallSite
1156 var method_lt
: nullable CallSite
1157 var method_successor
: nullable CallSite
1159 private fun do_type_iterator
(v
: TypeVisitor, mtype
: MType)
1161 if mtype
isa MNullType then
1162 v
.error
(self, "Type Error: `for` cannot iterate over `null`.")
1167 var objcla
= v
.get_mclass
(self, "Object")
1168 if objcla
== null then return
1170 # check iterator method
1171 var itdef
= v
.get_method
(self, mtype
, "iterator", n_expr
isa ASelfExpr)
1172 if itdef
== null then
1173 v
.error
(self, "Type Error: `for` expects a type providing an `iterator` method, got `{mtype}`.")
1176 self.method_iterator
= itdef
1178 # check that iterator return something
1179 var ittype
= itdef
.msignature
.return_mtype
1180 if ittype
== null then
1181 v
.error
(self, "Type Error: `for` expects the method `iterator` to return an `Iterator` or `MapIterator` type.")
1186 var colit_cla
= v
.try_get_mclass
(self, "Iterator")
1187 var mapit_cla
= v
.try_get_mclass
(self, "MapIterator")
1191 if colit_cla
!= null and v
.is_subtype
(ittype
, colit_cla
.get_mtype
([objcla
.mclass_type
.as_nullable
])) then
1193 var coltype
= ittype
.supertype_to
(v
.mmodule
, v
.anchor
, colit_cla
)
1194 var variables
= self.variables
1195 if variables
.length
!= 1 then
1196 v
.error
(self, "Type Error: `for` expects only one variable when using `Iterator`.")
1198 variables
.first
.declared_type
= coltype
.arguments
.first
1203 if mapit_cla
!= null and v
.is_subtype
(ittype
, mapit_cla
.get_mtype
([objcla
.mclass_type
.as_nullable
, objcla
.mclass_type
.as_nullable
])) then
1205 var coltype
= ittype
.supertype_to
(v
.mmodule
, v
.anchor
, mapit_cla
)
1206 var variables
= self.variables
1207 if variables
.length
!= 2 then
1208 v
.error
(self, "Type Error: `for` expects two variables when using `MapIterator`.")
1210 variables
[0].declared_type
= coltype
.arguments
[0]
1211 variables
[1].declared_type
= coltype
.arguments
[1]
1216 if not is_col
and not is_map
then
1217 v
.error
(self, "Type Error: `for` expects the method `iterator` to return an `Iterator` or `MapIterator` type.")
1221 # anchor formal and virtual types
1222 if mtype
.need_anchor
then mtype
= v
.anchor_to
(mtype
)
1224 mtype
= mtype
.undecorate
1225 self.coltype
= mtype
.as(MClassType)
1227 # get methods is_ok, next, item
1228 var ikdef
= v
.get_method
(self, ittype
, "is_ok", false)
1229 if ikdef
== null then
1230 v
.error
(self, "Type Error: `for` expects a method `is_ok` in type `{ittype}`.")
1233 self.method_is_ok
= ikdef
1235 var itemdef
= v
.get_method
(self, ittype
, "item", false)
1236 if itemdef
== null then
1237 v
.error
(self, "Type Error: `for` expects a method `item` in type `{ittype}`.")
1240 self.method_item
= itemdef
1242 var nextdef
= v
.get_method
(self, ittype
, "next", false)
1243 if nextdef
== null then
1244 v
.error
(self, "Type Error: `for` expects a method `next` in type {ittype}.")
1247 self.method_next
= nextdef
1249 self.method_finish
= v
.try_get_method
(self, ittype
, "finish", false)
1252 var keydef
= v
.get_method
(self, ittype
, "key", false)
1253 if keydef
== null then
1254 v
.error
(self, "Type Error: `for` expects a method `key` in type `{ittype}`.")
1257 self.method_key
= keydef
1260 if self.variables
.length
== 1 and n_expr
isa ARangeExpr then
1261 var variable
= variables
.first
1262 var vtype
= variable
.declared_type
.as(not null)
1264 if n_expr
isa AOrangeExpr then
1265 self.method_lt
= v
.get_method
(self, vtype
, "<", false)
1267 self.method_lt
= v
.get_method
(self, vtype
, "<=", false)
1270 self.method_successor
= v
.get_method
(self, vtype
, "successor", false)
1275 redef class AWithExpr
1276 var method_start
: nullable CallSite
1277 var method_finish
: nullable CallSite
1279 redef fun accept_typing
(v
: TypeVisitor)
1281 var mtype
= v
.visit_expr
(n_expr
)
1282 if mtype
== null then return
1284 method_start
= v
.get_method
(self, mtype
, "start", n_expr
isa ASelfExpr)
1285 method_finish
= v
.get_method
(self, mtype
, "finish", n_expr
isa ASelfExpr)
1287 v
.visit_stmt
(n_block
)
1288 self.mtype
= n_block
.mtype
1289 self.is_typed
= true
1293 redef class AAssertExpr
1294 redef fun accept_typing
(v
)
1296 v
.visit_expr_bool
(n_expr
)
1298 v
.visit_stmt
(n_else
)
1299 self.is_typed
= true
1304 redef fun accept_typing
(v
)
1306 v
.visit_expr_bool
(n_expr
)
1307 v
.visit_expr_bool
(n_expr2
)
1308 self.mtype
= v
.type_bool
(self)
1312 redef class AImpliesExpr
1313 redef fun accept_typing
(v
)
1315 v
.visit_expr_bool
(n_expr
)
1316 v
.visit_expr_bool
(n_expr2
)
1317 self.mtype
= v
.type_bool
(self)
1321 redef class AAndExpr
1322 redef fun accept_typing
(v
)
1324 v
.visit_expr_bool
(n_expr
)
1325 v
.visit_expr_bool
(n_expr2
)
1326 self.mtype
= v
.type_bool
(self)
1331 redef class ANotExpr
1332 redef fun accept_typing
(v
)
1334 v
.visit_expr_bool
(n_expr
)
1335 self.mtype
= v
.type_bool
(self)
1339 redef class AOrElseExpr
1340 redef fun accept_typing
(v
)
1342 var t1
= v
.visit_expr
(n_expr
)
1343 var t2
= v
.visit_expr
(n_expr2
)
1345 if t1
== null or t2
== null then
1349 if t1
isa MNullType then
1352 else if v
.can_be_null
(t1
) then
1356 var t
= v
.merge_types
(self, [t1
, t2
])
1358 var c
= v
.get_mclass
(self, "Object")
1359 if c
== null then return # forward error
1361 if v
.can_be_null
(t2
) then
1364 #v.error(self, "Type Error: ambiguous type {t1} vs {t2}")
1369 redef fun accept_post_typing
(v
)
1371 var t1
= n_expr
.mtype
1375 v
.check_can_be_null
(n_expr
, t1
)
1380 redef class ATrueExpr
1381 redef fun accept_typing
(v
)
1383 self.mtype
= v
.type_bool
(self)
1387 redef class AFalseExpr
1388 redef fun accept_typing
(v
)
1390 self.mtype
= v
.type_bool
(self)
1394 redef class AIntegerExpr
1395 redef fun accept_typing
(v
)
1397 var mclass
: nullable MClass = null
1398 if value
isa Byte then
1399 mclass
= v
.get_mclass
(self, "Byte")
1400 else if value
isa Int then
1401 mclass
= v
.get_mclass
(self, "Int")
1402 else if value
isa Int8 then
1403 mclass
= v
.get_mclass
(self, "Int8")
1404 else if value
isa Int16 then
1405 mclass
= v
.get_mclass
(self, "Int16")
1406 else if value
isa UInt16 then
1407 mclass
= v
.get_mclass
(self, "UInt16")
1408 else if value
isa Int32 then
1409 mclass
= v
.get_mclass
(self, "Int32")
1410 else if value
isa UInt32 then
1411 mclass
= v
.get_mclass
(self, "UInt32")
1413 if mclass
== null then return # Forward error
1414 self.mtype
= mclass
.mclass_type
1418 redef class AFloatExpr
1419 redef fun accept_typing
(v
)
1421 var mclass
= v
.get_mclass
(self, "Float")
1422 if mclass
== null then return # Forward error
1423 self.mtype
= mclass
.mclass_type
1427 redef class ACharExpr
1428 redef fun accept_typing
(v
)
1430 var mclass
= v
.get_mclass
(self, "Char")
1431 if mclass
== null then return # Forward error
1432 self.mtype
= mclass
.mclass_type
1436 redef class AStringFormExpr
1437 redef fun accept_typing
(v
)
1439 var mclass
= v
.get_mclass
(self, "String")
1440 if mclass
== null then return # Forward error
1441 self.mtype
= mclass
.mclass_type
1445 redef class ASuperstringExpr
1446 redef fun accept_typing
(v
)
1448 var mclass
= v
.get_mclass
(self, "String")
1449 if mclass
== null then return # Forward error
1450 self.mtype
= mclass
.mclass_type
1451 var objclass
= v
.get_mclass
(self, "Object")
1452 if objclass
== null then return # Forward error
1453 var objtype
= objclass
.mclass_type
1454 for nexpr
in self.n_exprs
do
1455 v
.visit_expr_subtype
(nexpr
, objtype
)
1460 redef class AArrayExpr
1461 # The `with_capacity` method on Array
1462 var with_capacity_callsite
: nullable CallSite
1464 # The `push` method on arrays
1465 var push_callsite
: nullable CallSite
1467 # The element of each type
1468 var element_mtype
: nullable MType
1470 # Set that `self` is a part of comprehension array `na`
1471 # If `self` is a `for`, or a `if`, then `set_comprehension` is recursively applied.
1472 private fun set_comprehension
(n
: nullable AExpr)
1476 else if n
isa AForExpr then
1477 set_comprehension
(n
.n_block
)
1478 else if n
isa AIfExpr then
1479 set_comprehension
(n
.n_then
)
1480 set_comprehension
(n
.n_else
)
1483 n
.comprehension
= self
1486 redef fun accept_typing
(v
)
1488 var mtype
: nullable MType = null
1489 var ntype
= self.n_type
1490 if ntype
!= null then
1491 mtype
= v
.resolve_mtype
(ntype
)
1492 if mtype
== null then return # Skip error
1494 var mtypes
= new Array[nullable MType]
1496 for e
in self.n_exprs
do
1497 var t
= v
.visit_expr
(e
)
1501 set_comprehension
(e
)
1502 if mtype
!= null then
1503 if v
.check_subtype
(e
, t
, mtype
, false) == null then return # Forward error
1504 if t
== mtype
then useless
= true
1509 if mtype
== null then
1510 # Ensure monotony for type adaptation on loops
1511 if self.element_mtype
!= null then mtypes
.add
self.element_mtype
1512 mtype
= v
.merge_types
(self, mtypes
)
1514 if mtype
== null or mtype
isa MNullType then
1515 v
.error
(self, "Type Error: ambiguous array type {mtypes.join(" ")}")
1519 assert ntype
!= null
1520 v
.modelbuilder
.warning
(ntype
, "useless-type", "Warning: useless type declaration `{mtype}` in literal Array since it can be inferred from the elements type.")
1523 self.element_mtype
= mtype
1525 var mclass
= v
.get_mclass
(self, "Array")
1526 if mclass
== null then return # Forward error
1527 var array_mtype
= mclass
.get_mtype
([mtype
])
1529 with_capacity_callsite
= v
.get_method
(self, array_mtype
, "with_capacity", false)
1530 push_callsite
= v
.get_method
(self, array_mtype
, "push", false)
1532 self.mtype
= array_mtype
1536 redef class ARangeExpr
1537 var init_callsite
: nullable CallSite
1539 redef fun accept_typing
(v
)
1541 var discrete_class
= v
.get_mclass
(self, "Discrete")
1542 if discrete_class
== null then return # Forward error
1543 var discrete_type
= discrete_class
.intro
.bound_mtype
1544 var t1
= v
.visit_expr_subtype
(self.n_expr
, discrete_type
)
1545 var t2
= v
.visit_expr_subtype
(self.n_expr2
, discrete_type
)
1546 if t1
== null or t2
== null then return
1547 var mclass
= v
.get_mclass
(self, "Range")
1548 if mclass
== null then return # Forward error
1550 if v
.is_subtype
(t1
, t2
) then
1551 mtype
= mclass
.get_mtype
([t2
])
1552 else if v
.is_subtype
(t2
, t1
) then
1553 mtype
= mclass
.get_mtype
([t1
])
1555 v
.error
(self, "Type Error: cannot create range: `{t1}` vs `{t2}`.")
1561 # get the constructor
1563 if self isa ACrangeExpr then
1564 callsite
= v
.get_method
(self, mtype
, "init", false)
1565 else if self isa AOrangeExpr then
1566 callsite
= v
.get_method
(self, mtype
, "without_last", false)
1570 init_callsite
= callsite
1574 redef class ANullExpr
1575 redef fun accept_typing
(v
)
1577 self.mtype
= v
.mmodule
.model
.null_type
1581 redef class AIsaExpr
1582 # The static type to cast to.
1583 # (different from the static type of the expression that is `Bool`).
1584 var cast_type
: nullable MType
1585 redef fun accept_typing
(v
)
1587 v
.visit_expr
(n_expr
)
1589 var mtype
= v
.resolve_mtype
(n_type
)
1591 self.cast_type
= mtype
1593 var variable
= self.n_expr
.its_variable
1594 if variable
!= null then
1595 #var orig = self.n_expr.mtype
1596 #var from = if orig != null then orig.to_s else "invalid"
1597 #var to = if mtype != null then mtype.to_s else "invalid"
1598 #debug("adapt {variable}: {from} -> {to}")
1599 self.after_flow_context
.when_true
.set_var
(v
, variable
, mtype
)
1602 self.mtype
= v
.type_bool
(self)
1605 redef fun accept_post_typing
(v
)
1607 v
.check_expr_cast
(self, self.n_expr
, self.n_type
)
1611 redef class AAsCastExpr
1612 redef fun accept_typing
(v
)
1614 v
.visit_expr
(n_expr
)
1616 self.mtype
= v
.resolve_mtype
(n_type
)
1619 redef fun accept_post_typing
(v
)
1621 v
.check_expr_cast
(self, self.n_expr
, self.n_type
)
1625 redef class AAsNotnullExpr
1626 redef fun accept_typing
(v
)
1628 var mtype
= v
.visit_expr
(self.n_expr
)
1629 if mtype
== null then return # Forward error
1631 if mtype
isa MNullType then
1632 v
.error
(self, "Type Error: `as(not null)` on `null`.")
1636 if v
.can_be_null
(mtype
) then
1637 mtype
= mtype
.as_notnull
1643 redef fun accept_post_typing
(v
)
1645 var mtype
= n_expr
.mtype
1646 if mtype
== null then return
1647 v
.check_can_be_null
(n_expr
, mtype
)
1651 redef class AParExpr
1652 redef fun accept_typing
(v
)
1654 self.mtype
= v
.visit_expr
(self.n_expr
)
1658 redef class AOnceExpr
1659 redef fun accept_typing
(v
)
1661 self.mtype
= v
.visit_expr
(self.n_expr
)
1665 redef class ASelfExpr
1666 redef var its_variable
: nullable Variable
1667 redef fun accept_typing
(v
)
1669 if v
.is_toplevel_context
and not self isa AImplicitSelfExpr then
1670 v
.error
(self, "Error: `self` cannot be used in top-level method.")
1672 var variable
= v
.selfvariable
1673 self.its_variable
= variable
1674 self.mtype
= v
.get_variable
(self, variable
)
1678 redef class AImplicitSelfExpr
1679 # Is the implicit receiver `sys`?
1681 # By default, the implicit receiver is `self`.
1682 # But when there is not method for `self`, `sys` is used as a fall-back.
1683 # Is this case this flag is set to `true`.
1687 ## MESSAGE SENDING AND PROPERTY
1689 redef class ASendExpr
1690 # The property invoked by the send.
1691 var callsite
: nullable CallSite
1693 redef fun accept_typing
(v
)
1695 var nrecv
= self.n_expr
1696 var recvtype
= v
.visit_expr
(nrecv
)
1697 var name
= self.property_name
1698 var node
= self.property_node
1700 if recvtype
== null then return # Forward error
1703 var unsafe_type
= v
.anchor_to
(recvtype
)
1704 var mproperty
= v
.try_get_mproperty_by_name2
(node
, unsafe_type
, name
)
1705 if mproperty
== null and nrecv
isa AImplicitSelfExpr then
1706 # Special fall-back search in `sys` when noting found in the implicit receiver.
1707 var sysclass
= v
.try_get_mclass
(node
, "Sys")
1708 if sysclass
!= null then
1709 var systype
= sysclass
.mclass_type
1710 mproperty
= v
.try_get_mproperty_by_name2
(node
, systype
, name
)
1711 if mproperty
!= null then
1712 callsite
= v
.get_method
(node
, systype
, name
, false)
1713 if callsite
== null then return # Forward error
1714 # Update information, we are looking at `sys` now, not `self`
1716 nrecv
.its_variable
= null
1717 nrecv
.mtype
= systype
1722 if callsite
== null then
1723 # If still nothing, just exit
1724 callsite
= v
.get_method
(node
, recvtype
, name
, nrecv
isa ASelfExpr)
1725 if callsite
== null then return
1728 self.callsite
= callsite
1729 var msignature
= callsite
.msignature
1731 var args
= compute_raw_arguments
1733 callsite
.check_signature
(v
, node
, args
)
1735 if callsite
.mproperty
.is_init
then
1736 var vmpropdef
= v
.mpropdef
1737 if not (vmpropdef
isa MMethodDef and vmpropdef
.mproperty
.is_init
) then
1738 v
.error
(node
, "Error: an `init` can only be called from another `init`.")
1740 if vmpropdef
isa MMethodDef and vmpropdef
.mproperty
.is_root_init
and not callsite
.mproperty
.is_root_init
then
1741 v
.error
(node
, "Error: `{vmpropdef}` cannot call a factory `{callsite.mproperty}`.")
1745 var ret
= msignature
.return_mtype
1749 self.is_typed
= true
1753 # The name of the property
1754 # Each subclass simply provide the correct name.
1755 private fun property_name
: String is abstract
1757 # The node identifying the name (id, operator, etc) for messages.
1759 # Is `self` by default
1760 private fun property_node
: ANode do return self
1762 # An array of all arguments (excluding self)
1763 fun raw_arguments
: Array[AExpr] do return compute_raw_arguments
1765 private fun compute_raw_arguments
: Array[AExpr] is abstract
1768 redef class ABinopExpr
1769 redef fun compute_raw_arguments
do return [n_expr2
]
1770 redef fun property_name
do return operator
1771 redef fun property_node
do return n_op
1774 redef class AEqFormExpr
1775 redef fun accept_typing
(v
)
1781 redef fun accept_post_typing
(v
)
1783 var mtype
= n_expr
.mtype
1784 var mtype2
= n_expr2
.mtype
1786 if mtype
== null or mtype2
== null then return
1788 if not mtype2
isa MNullType then return
1790 v
.check_can_be_null
(n_expr
, mtype
)
1794 redef class AUnaryopExpr
1795 redef fun property_name
do return "unary {operator}"
1796 redef fun compute_raw_arguments
do return new Array[AExpr]
1800 redef class ACallExpr
1801 redef fun property_name
do return n_qid
.n_id
.text
1802 redef fun property_node
do return n_qid
1803 redef fun compute_raw_arguments
do return n_args
.to_a
1806 redef class ACallAssignExpr
1807 redef fun property_name
do return n_qid
.n_id
.text
+ "="
1808 redef fun property_node
do return n_qid
1809 redef fun compute_raw_arguments
1811 var res
= n_args
.to_a
1817 redef class ABraExpr
1818 redef fun property_name
do return "[]"
1819 redef fun compute_raw_arguments
do return n_args
.to_a
1822 redef class ABraAssignExpr
1823 redef fun property_name
do return "[]="
1824 redef fun compute_raw_arguments
1826 var res
= n_args
.to_a
1832 redef class ASendReassignFormExpr
1833 # The property invoked for the writing
1834 var write_callsite
: nullable CallSite
1836 redef fun accept_typing
(v
)
1838 var recvtype
= v
.visit_expr
(self.n_expr
)
1839 var name
= self.property_name
1840 var node
= self.property_node
1842 if recvtype
== null then return # Forward error
1844 var for_self
= self.n_expr
isa ASelfExpr
1845 var callsite
= v
.get_method
(node
, recvtype
, name
, for_self
)
1847 if callsite
== null then return
1848 self.callsite
= callsite
1850 var args
= compute_raw_arguments
1852 callsite
.check_signature
(v
, node
, args
)
1854 var readtype
= callsite
.msignature
.return_mtype
1855 if readtype
== null then
1856 v
.error
(node
, "Error: `{name}` is not a function.")
1860 var wcallsite
= v
.get_method
(node
, recvtype
, name
+ "=", self.n_expr
isa ASelfExpr)
1861 if wcallsite
== null then return
1862 self.write_callsite
= wcallsite
1864 var wtype
= self.resolve_reassignment
(v
, readtype
, wcallsite
.msignature
.mparameters
.last
.mtype
)
1865 if wtype
== null then return
1867 args
= args
.to_a
# duplicate so raw_arguments keeps only the getter args
1868 args
.add
(self.n_value
)
1869 wcallsite
.check_signature
(v
, node
, args
)
1871 self.is_typed
= true
1875 redef class ACallReassignExpr
1876 redef fun property_name
do return n_qid
.n_id
.text
1877 redef fun property_node
do return n_qid
.n_id
1878 redef fun compute_raw_arguments
do return n_args
.to_a
1881 redef class ABraReassignExpr
1882 redef fun property_name
do return "[]"
1883 redef fun compute_raw_arguments
do return n_args
.to_a
1886 redef class AInitExpr
1887 redef fun property_name
do return "init"
1888 redef fun property_node
do return n_kwinit
1889 redef fun compute_raw_arguments
do return n_args
.to_a
1893 fun to_a
: Array[AExpr] do return self.n_exprs
.to_a
1898 redef class ASuperExpr
1899 # The method to call if the super is in fact a 'super init call'
1900 # Note: if the super is a normal call-next-method, then this attribute is null
1901 var callsite
: nullable CallSite
1903 # The method to call is the super is a standard `call-next-method` super-call
1904 # Note: if the super is a special super-init-call, then this attribute is null
1905 var mpropdef
: nullable MMethodDef
1907 redef fun accept_typing
(v
)
1909 var anchor
= v
.anchor
1910 assert anchor
!= null
1911 var recvtype
= v
.get_variable
(self, v
.selfvariable
)
1912 assert recvtype
!= null
1913 var mproperty
= v
.mpropdef
.mproperty
1914 if not mproperty
isa MMethod then
1915 v
.error
(self, "Error: `super` only usable in a `method`.")
1918 var superprops
= mproperty
.lookup_super_definitions
(v
.mmodule
, anchor
)
1919 if superprops
.length
== 0 then
1920 if mproperty
.is_init
and v
.mpropdef
.is_intro
then
1921 process_superinit
(v
)
1924 v
.error
(self, "Error: no super method to call for `{mproperty}`.")
1927 # FIXME: covariance of return type in linear extension?
1928 var superprop
= superprops
.first
1930 var msignature
= superprop
.msignature
.as(not null)
1931 msignature
= v
.resolve_for
(msignature
, recvtype
, true).as(MSignature)
1932 var args
= self.n_args
.to_a
1933 if args
.length
> 0 then
1934 signaturemap
= v
.check_signature
(self, args
, mproperty
, msignature
)
1936 self.mtype
= msignature
.return_mtype
1937 self.is_typed
= true
1938 v
.mpropdef
.has_supercall
= true
1939 mpropdef
= v
.mpropdef
.as(MMethodDef)
1942 # The mapping used on the call to associate arguments to parameters.
1943 # If null then no specific association is required.
1944 var signaturemap
: nullable SignatureMap
1946 private fun process_superinit
(v
: TypeVisitor)
1948 var anchor
= v
.anchor
1949 assert anchor
!= null
1950 var recvtype
= v
.get_variable
(self, v
.selfvariable
)
1951 assert recvtype
!= null
1952 var mpropdef
= v
.mpropdef
1953 assert mpropdef
isa MMethodDef
1954 var mproperty
= mpropdef
.mproperty
1955 var superprop
: nullable MMethodDef = null
1956 for msupertype
in mpropdef
.mclassdef
.supertypes
do
1957 msupertype
= msupertype
.anchor_to
(v
.mmodule
, anchor
)
1958 var errcount
= v
.modelbuilder
.toolcontext
.error_count
1959 var candidate
= v
.try_get_mproperty_by_name2
(self, msupertype
, mproperty
.name
).as(nullable MMethod)
1960 if candidate
== null then
1961 if v
.modelbuilder
.toolcontext
.error_count
> errcount
then return # Forward error
1962 continue # Try next super-class
1964 if superprop
!= null and candidate
.is_root_init
then
1967 if superprop
!= null and superprop
.mproperty
!= candidate
and not superprop
.mproperty
.is_root_init
then
1968 v
.error
(self, "Error: conflicting super constructor to call for `{mproperty}`: `{candidate.full_name}`, `{superprop.mproperty.full_name}`")
1971 var candidatedefs
= candidate
.lookup_definitions
(v
.mmodule
, anchor
)
1972 if superprop
!= null and superprop
.mproperty
== candidate
then
1973 if superprop
== candidatedefs
.first
then continue
1974 candidatedefs
.add
(superprop
)
1976 if candidatedefs
.length
> 1 then
1977 v
.error
(self, "Error: conflicting property definitions for property `{mproperty}` in `{recvtype}`: {candidatedefs.join(", ")}")
1980 superprop
= candidatedefs
.first
1982 if superprop
== null then
1983 v
.error
(self, "Error: no super method to call for `{mproperty}`.")
1987 var msignature
= superprop
.new_msignature
or else superprop
.msignature
.as(not null)
1988 msignature
= v
.resolve_for
(msignature
, recvtype
, true).as(MSignature)
1990 var callsite
= new CallSite(hot_location
, recvtype
, v
.mmodule
, v
.anchor
, true, superprop
.mproperty
, superprop
, msignature
, false)
1991 self.callsite
= callsite
1993 var args
= self.n_args
.to_a
1994 if args
.length
> 0 then
1995 callsite
.check_signature
(v
, self, args
)
1997 # Check there is at least enough parameters
1998 if mpropdef
.msignature
.arity
< msignature
.arity
then
1999 v
.error
(self, "Error: not enough implicit arguments to pass. Got `{mpropdef.msignature.arity}`, expected at least `{msignature.arity}`. Signature is `{msignature}`.")
2002 # Check that each needed parameter is conform
2004 for sp
in msignature
.mparameters
do
2005 var p
= mpropdef
.msignature
.mparameters
[i
]
2006 if not v
.is_subtype
(p
.mtype
, sp
.mtype
) then
2007 v
.error
(self, "Type Error: expected argument #{i} of type `{sp.mtype}`, got implicit argument `{p.name}` of type `{p.mtype}`. Signature is {msignature}")
2014 self.is_typed
= true
2020 redef class ANewExpr
2021 # The constructor invoked by the new.
2022 var callsite
: nullable CallSite
2024 # The designated type
2025 var recvtype
: nullable MClassType
2027 redef fun accept_typing
(v
)
2029 var recvtype
= v
.resolve_mtype
(self.n_type
)
2030 if recvtype
== null then return
2032 if not recvtype
isa MClassType then
2033 if recvtype
isa MNullableType then
2034 v
.error
(self, "Type Error: cannot instantiate the nullable type `{recvtype}`.")
2036 else if recvtype
isa MFormalType then
2037 v
.error
(self, "Type Error: cannot instantiate the formal type `{recvtype}`.")
2040 v
.error
(self, "Type Error: cannot instantiate the type `{recvtype}`.")
2045 self.recvtype
= recvtype
2046 var kind
= recvtype
.mclass
.kind
2049 var nqid
= self.n_qid
2051 if nqid
!= null then
2052 name
= nqid
.n_id
.text
2058 if name
== "intern" then
2059 if kind
!= concrete_kind
then
2060 v
.error
(self, "Type Error: cannot instantiate {kind} {recvtype}.")
2063 if n_args
.n_exprs
.not_empty
then
2064 v
.error
(n_args
, "Type Error: the intern constructor expects no arguments.")
2068 self.mtype
= recvtype
2072 var callsite
= v
.get_method
(node
, recvtype
, name
, false)
2073 if callsite
== null then return
2075 if not callsite
.mproperty
.is_new
then
2076 if kind
!= concrete_kind
then
2077 v
.error
(self, "Type Error: cannot instantiate {kind} `{recvtype}`.")
2080 self.mtype
= recvtype
2082 self.mtype
= callsite
.msignature
.return_mtype
2083 assert self.mtype
!= null
2086 self.callsite
= callsite
2088 if not callsite
.mproperty
.is_init_for
(recvtype
.mclass
) then
2089 v
.error
(self, "Error: `{name}` is not a constructor.")
2093 var args
= n_args
.to_a
2094 callsite
.check_signature
(v
, node
, args
)
2100 redef class AAttrFormExpr
2101 # The attribute accessed.
2102 var mproperty
: nullable MAttribute
2104 # The static type of the attribute.
2105 var attr_type
: nullable MType
2107 # Resolve the attribute accessed.
2108 private fun resolve_property
(v
: TypeVisitor)
2110 var recvtype
= v
.visit_expr
(self.n_expr
)
2111 if recvtype
== null then return # Skip error
2112 var node
= self.n_id
2113 var name
= node
.text
2114 if recvtype
isa MNullType then
2115 v
.error
(node
, "Error: attribute `{name}` access on `null`.")
2119 var unsafe_type
= v
.anchor_to
(recvtype
)
2120 var mproperty
= v
.try_get_mproperty_by_name2
(node
, unsafe_type
, name
)
2121 if mproperty
== null then
2122 v
.modelbuilder
.error
(node
, "Error: attribute `{name}` does not exist in `{recvtype}`.")
2125 assert mproperty
isa MAttribute
2126 self.mproperty
= mproperty
2128 var mpropdefs
= mproperty
.lookup_definitions
(v
.mmodule
, unsafe_type
)
2129 assert mpropdefs
.length
== 1
2130 var mpropdef
= mpropdefs
.first
2131 var attr_type
= mpropdef
.static_mtype
2132 if attr_type
== null then return # skip error
2133 attr_type
= v
.resolve_for
(attr_type
, recvtype
, self.n_expr
isa ASelfExpr)
2134 self.attr_type
= attr_type
2138 redef class AAttrExpr
2139 redef fun accept_typing
(v
)
2141 self.resolve_property
(v
)
2142 self.mtype
= self.attr_type
2147 redef class AAttrAssignExpr
2148 redef fun accept_typing
(v
)
2150 self.resolve_property
(v
)
2151 var mtype
= self.attr_type
2153 v
.visit_expr_subtype
(self.n_value
, mtype
)
2154 self.is_typed
= mtype
!= null
2158 redef class AAttrReassignExpr
2159 redef fun accept_typing
(v
)
2161 self.resolve_property
(v
)
2162 var mtype
= self.attr_type
2163 if mtype
== null then return # Skip error
2165 var rettype
= self.resolve_reassignment
(v
, mtype
, mtype
)
2167 self.is_typed
= rettype
!= null
2171 redef class AIssetAttrExpr
2172 redef fun accept_typing
(v
)
2174 self.resolve_property
(v
)
2175 var mtype
= self.attr_type
2176 if mtype
== null then return # Skip error
2178 var recvtype
= self.n_expr
.mtype
.as(not null)
2179 var bound
= v
.resolve_for
(mtype
, recvtype
, false)
2180 if bound
isa MNullableType then
2181 v
.error
(n_id
, "Type Error: `isset` on a nullable attribute.")
2183 self.mtype
= v
.type_bool
(self)
2187 redef class AVarargExpr
2188 redef fun accept_typing
(v
)
2190 # This kind of pseudo-expression can be only processed trough a signature
2191 # See `check_signature`
2192 # Other cases are a syntax error.
2193 v
.error
(self, "Syntax Error: unexpected `...`.")
2199 redef class ADebugTypeExpr
2200 redef fun accept_typing
(v
)
2202 var expr
= v
.visit_expr
(self.n_expr
)
2203 if expr
== null then return
2204 var unsafe
= v
.anchor_to
(expr
)
2205 var ntype
= self.n_type
2206 var mtype
= v
.resolve_mtype
(ntype
)
2207 if mtype
!= null and mtype
!= expr
then
2208 var umtype
= v
.anchor_to
(mtype
)
2209 v
.modelbuilder
.warning
(self, "debug", "Found type {expr} (-> {unsafe}), expected {mtype} (-> {umtype})")
2211 self.is_typed
= true