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 if not param
.is_vararg
then
494 var paramtype
= param
.mtype
495 self.visit_expr_subtype
(arg
, paramtype
)
497 check_one_vararg
(arg
, param
)
501 if min_arity
> 0 then
502 if last_is_padded
then min_arity
+= 1
503 if min_arity
< msignature
.arity
then
504 modelbuilder
.error
(node
, "Error: expected at least {min_arity} argument(s) for `{mproperty}{msignature}`; got {args.length}. See introduction at `{mproperty.full_name}`.")
506 modelbuilder
.error
(node
, "Error: expected {min_arity} argument(s) for `{mproperty}{msignature}`; got {args.length}. See introduction at `{mproperty.full_name}`.")
511 # Third, check varargs
512 if vararg_rank
>= 0 then
513 var paramtype
= msignature
.mparameters
[vararg_rank
].mtype
514 var first
= args
[vararg_rank
]
515 if vararg_decl
== 0 then
516 if not check_one_vararg
(first
, msignature
.mparameters
[vararg_rank
]) then return null
518 first
.vararg_decl
= vararg_decl
+ 1
519 for i
in [vararg_rank
..vararg_rank
+vararg_decl
] do
520 self.visit_expr_subtype
(args
[i
], paramtype
)
528 # Check an expression as a single vararg.
529 # The main point of the method if to handle the case of reversed vararg (see `AVarargExpr`)
530 fun check_one_vararg
(arg
: AExpr, param
: MParameter): Bool
532 var paramtype
= param
.mtype
533 var mclass
= get_mclass
(arg
, "Array")
534 if mclass
== null then return false # Forward error
535 var array_mtype
= mclass
.get_mtype
([paramtype
])
536 if arg
isa AVarargExpr then
537 self.visit_expr_subtype
(arg
.n_expr
, array_mtype
)
538 arg
.mtype
= arg
.n_expr
.mtype
540 # only one vararg, maybe `...` was forgot, so be gentle!
541 var t
= visit_expr
(arg
)
542 if t
== null then return false # Forward error
543 if not is_subtype
(t
, paramtype
) and is_subtype
(t
, array_mtype
) then
544 # Not acceptable but could be a `...`
545 error
(arg
, "Type Error: expected `{paramtype}`, got `{t}`. Is an ellipsis `...` missing on the argument?")
548 # Standard valid vararg, finish the job
550 self.visit_expr_subtype
(arg
, paramtype
)
555 fun error
(node
: ANode, message
: String)
557 self.modelbuilder
.error
(node
, message
)
560 fun get_variable
(node
: AExpr, variable
: Variable): nullable MType
562 if not variable
.is_adapted
then return variable
.declared_type
564 var flow
= node
.after_flow_context
565 if flow
== null then return null # skip error
567 if flow
.vars
.has_key
(variable
) then
568 return flow
.vars
[variable
]
570 #node.debug("*** START Collected for {variable}")
571 var mtypes
= flow
.collect_types
(variable
)
572 #node.debug("**** END Collected for {variable}")
573 if mtypes
.length
== 0 then
574 return variable
.declared_type
575 else if mtypes
.length
== 1 then
578 var res
= merge_types
(node
,mtypes
)
579 if res
== null then res
= variable
.declared_type
585 # Some variables where type-adapted during the visit
588 # Some loops had been visited during the visit
591 fun set_variable
(node
: AExpr, variable
: Variable, mtype
: nullable MType)
593 var flow
= node
.after_flow_context
596 flow
.set_var
(self, variable
, mtype
)
599 fun merge_types
(node
: ANode, col
: Array[nullable MType]): nullable MType
601 if col
.length
== 1 then return col
.first
603 if t1
== null then continue # return null
606 if t2
== null then continue # return null
607 if can_be_null
(t2
) and not can_be_null
(t1
) then
610 if not is_subtype
(t2
, t1
) then found
= false
613 #print "merge {col.join(" ")} -> {t1}"
617 #self.modelbuilder.warning(node, "Type Error: {col.length} conflicting types: <{col.join(", ")}>")
622 # Mapping between parameters and arguments in a call.
624 # Parameters and arguments are not stored in the class but referenced by their position (starting from 0)
626 # The point of this class is to help engine and other things to map arguments in the AST to parameters of the model.
628 # Associate a parameter to an argument
629 var map
= new ArrayMap[Int, Int]
632 # A specific method call site with its associated informations.
636 # The associated location of the callsite
637 var location
: Location
639 # The static type of the receiver (possibly unresolved)
642 # The module where the callsite is present
645 # The anchor to use with `recv` or `msignature`
646 var anchor
: nullable MClassType
648 # Is the receiver self?
649 # If "for_self", virtual types of the signature are kept
650 # If "not_for_self", virtual type are erased
651 var recv_is_self
: Bool
653 # The designated method
654 var mproperty
: MMethod
656 # The statically designated method definition
657 # The most specif one, it is.
658 var mpropdef
: MMethodDef
660 # The resolved signature for the receiver
661 var msignature
: MSignature
663 # Is a implicit cast required on erasure typing policy?
664 var erasure_cast
: Bool
666 # The mapping used on the call to associate arguments to parameters
667 # If null then no specific association is required.
668 var signaturemap
: nullable SignatureMap = null
670 private fun check_signature
(v
: TypeVisitor, node
: ANode, args
: Array[AExpr]): Bool
672 var map
= v
.check_signature
(node
, args
, self.mproperty
, self.msignature
)
674 if map
== null then is_broken
= true
680 # The declared type of the variable
681 var declared_type
: nullable MType is writable
683 # Was the variable type-adapted?
684 # This is used to speedup type retrieval while it remains `false`
685 private var is_adapted
= false
688 redef class FlowContext
689 # Store changes of types because of type evolution
690 private var vars
= new HashMap[Variable, nullable MType]
692 # Adapt the variable to a static type
693 # Warning1: do not modify vars directly.
694 # Warning2: sub-flow may have cached a unadapted variable
695 private fun set_var
(v
: TypeVisitor, variable
: Variable, mtype
: nullable MType)
697 if variable
.declared_type
== mtype
and not variable
.is_adapted
then return
698 if vars
.has_key
(variable
) and vars
[variable
] == mtype
then return
699 self.vars
[variable
] = mtype
701 variable
.is_adapted
= true
702 #node.debug "set {variable} to {mtype or else "X"}"
705 # Look in the flow and previous flow and collect all first reachable type adaptation of a local variable
706 private fun collect_types
(variable
: Variable): Array[nullable MType]
708 #node.debug "flow for {variable}"
709 var res
= new Array[nullable MType]
712 var seen
= new HashSet[FlowContext]
713 while not todo
.is_empty
do
715 if f
.is_unreachable
then continue
716 if seen
.has
(f
) then continue
719 if f
.vars
.has_key
(variable
) then
720 # Found something. Collect it and do not process further on this path
721 res
.add f
.vars
[variable
]
722 #f.node.debug "process {variable}: got {f.vars[variable] or else "X"}"
724 todo
.add_all f
.previous
726 if f
.previous
.is_empty
then
727 # Root flowcontext mean a parameter or something related
728 res
.add variable
.declared_type
729 #f.node.debug "root process {variable}: got {variable.declared_type or else "X"}"
733 #self.node.debug "##### end flow for {variable}: {res.join(" ")}"
739 # The entry point of the whole typing analysis
740 fun do_typing
(modelbuilder
: ModelBuilder)
744 # The variable associated to the receiver (if any)
745 var selfvariable
: nullable Variable
748 redef class AMethPropdef
749 redef fun do_typing
(modelbuilder
: ModelBuilder)
751 var mpropdef
= self.mpropdef
752 if mpropdef
== null then return # skip error
754 var v
= new TypeVisitor(modelbuilder
, mpropdef
.mclassdef
.mmodule
, mpropdef
)
755 self.selfvariable
= v
.selfvariable
757 var mmethoddef
= self.mpropdef
.as(not null)
758 var msignature
= mmethoddef
.msignature
759 if msignature
== null then return # skip error
760 for i
in [0..msignature
.arity
[ do
761 var mtype
= msignature
.mparameters
[i
].mtype
762 if msignature
.vararg_rank
== i
then
763 var arrayclass
= v
.get_mclass
(self.n_signature
.n_params
[i
], "Array")
764 if arrayclass
== null then return # Skip error
765 mtype
= arrayclass
.get_mtype
([mtype
])
767 var variable
= self.n_signature
.n_params
[i
].variable
768 assert variable
!= null
769 variable
.declared_type
= mtype
772 var nblock
= self.n_block
773 if nblock
== null then return
778 if not v
.has_loop
or not v
.dirty
then break
781 var post_visitor
= new PostTypingVisitor(v
)
782 post_visitor
.enter_visit
(self)
784 if not nblock
.after_flow_context
.is_unreachable
and msignature
.return_mtype
!= null then
785 # We reach the end of the function without having a return, it is bad
786 v
.error
(self, "Error: reached end of function; expected `return` with a value.")
791 private class PostTypingVisitor
793 var type_visitor
: TypeVisitor
794 redef fun visit
(n
) do
796 n
.accept_post_typing
(type_visitor
)
797 if n
isa AExpr and n
.mtype
== null and not n
.is_typed
then
804 private fun accept_post_typing
(v
: TypeVisitor) do end
807 redef class AAttrPropdef
808 redef fun do_typing
(modelbuilder
: ModelBuilder)
810 if not has_value
then return
812 var mpropdef
= self.mreadpropdef
813 if mpropdef
== null or mpropdef
.msignature
== null then return # skip error
815 var v
= new TypeVisitor(modelbuilder
, mpropdef
.mclassdef
.mmodule
, mpropdef
)
816 self.selfvariable
= v
.selfvariable
818 var nexpr
= self.n_expr
819 if nexpr
!= null then
820 var mtype
= self.mtype
821 v
.visit_expr_subtype
(nexpr
, mtype
)
823 var nblock
= self.n_block
824 if nblock
!= null then
826 if not nblock
.after_flow_context
.is_unreachable
then
827 # We reach the end of the init without having a return, it is bad
828 v
.error
(self, "Error: reached end of block; expected `return`.")
837 # The static type of the expression.
838 # null if self is a statement or in case of error
839 var mtype
: nullable MType = null
841 # Is the statement correctly typed?
842 # Used to distinguish errors and statements when `mtype == null`
843 var is_typed
: Bool = false
845 # If required, the following implicit cast `.as(XXX)`
846 # Such a cast may by required after evaluating the expression when
847 # a unsafe operation is detected (silently accepted by the Nit language).
848 # The attribute is computed by `check_subtype`
849 var implicit_cast_to
: nullable MType = null
851 # Return the variable read (if any)
852 # Used to perform adaptive typing
853 fun its_variable
: nullable Variable do return null
855 private fun accept_typing
(v
: TypeVisitor)
857 v
.error
(self, "no implemented accept_typing for {self.class_name}")
860 # Is non-null if `self` is a leaf of a comprehension array construction.
861 # In this case, the enclosing literal array node is designated.
862 # The result of the evaluation of `self` must be
863 # stored inside the designated array (there is an implicit `push`)
864 var comprehension
: nullable AArrayExpr = null
866 # It indicates the number of arguments collected as a vararg.
868 # When 0, the argument is used as is, without transformation.
869 # When 1, the argument is transformed into an singleton array.
870 # Above 1, the arguments and the next ones are transformed into a common array.
872 # This attribute is meaning less on expressions not used as attributes.
873 var vararg_decl
: Int = 0
876 redef class ABlockExpr
877 redef fun accept_typing
(v
)
879 for e
in self.n_expr
do v
.visit_stmt
(e
)
883 # The type of a blockexpr is the one of the last expression (or null if empty)
886 if self.n_expr
.is_empty
then return null
887 return self.n_expr
.last
.mtype
891 redef class AVardeclExpr
892 redef fun accept_typing
(v
)
894 var variable
= self.variable
895 if variable
== null then return # Skip error
897 var ntype
= self.n_type
898 var mtype
: nullable MType
899 if ntype
== null then
902 mtype
= v
.resolve_mtype
(ntype
)
903 if mtype
== null then return # Skip error
906 var nexpr
= self.n_expr
907 if nexpr
!= null then
908 if mtype
!= null then
909 var etype
= v
.visit_expr_subtype
(nexpr
, mtype
)
910 if etype
== mtype
then
912 v
.modelbuilder
.advice
(ntype
, "useless-type", "Warning: useless type definition for variable `{variable.name}`")
915 mtype
= v
.visit_expr
(nexpr
)
916 if mtype
== null then return # Skip error
921 if mtype
== null or mtype
isa MNullType then
922 var objclass
= v
.get_mclass
(self, "Object")
923 if objclass
== null then return # skip error
924 decltype
= objclass
.mclass_type
.as_nullable
925 if mtype
== null then mtype
= decltype
928 variable
.declared_type
= decltype
929 v
.set_variable
(self, variable
, mtype
)
931 #debug("var {variable}: {mtype}")
939 redef fun its_variable
do return self.variable
940 redef fun accept_typing
(v
)
942 var variable
= self.variable
943 if variable
== null then return # Skip error
945 var mtype
= v
.get_variable
(self, variable
)
946 if mtype
!= null then
947 #debug("{variable} is {mtype}")
949 #debug("{variable} is untyped")
956 redef class AVarAssignExpr
957 redef fun accept_typing
(v
)
959 var variable
= self.variable
960 assert variable
!= null
962 var mtype
= v
.visit_expr_subtype
(n_value
, variable
.declared_type
)
964 v
.set_variable
(self, variable
, mtype
)
970 redef class AReassignFormExpr
971 # The method designed by the reassign operator.
972 var reassign_callsite
: nullable CallSite
974 var read_type
: nullable MType = null
976 # Determine the `reassign_property`
977 # `readtype` is the type of the reading of the left value.
978 # `writetype` is the type of the writing of the left value.
979 # (Because of `ACallReassignExpr`, both can be different.
980 # Return the static type of the value to store.
981 private fun resolve_reassignment
(v
: TypeVisitor, readtype
, writetype
: MType): nullable MType
983 var reassign_name
= self.n_assign_op
.operator
985 self.read_type
= readtype
987 var callsite
= v
.get_method
(self.n_assign_op
, readtype
, reassign_name
, false)
988 if callsite
== null then return null # Skip error
989 self.reassign_callsite
= callsite
991 var msignature
= callsite
.msignature
992 var rettype
= msignature
.return_mtype
993 assert msignature
.arity
== 1 and rettype
!= null
995 var value_type
= v
.visit_expr_subtype
(self.n_value
, msignature
.mparameters
.first
.mtype
)
996 if value_type
== null then return null # Skip error
998 v
.check_subtype
(self, rettype
, writetype
, false)
1003 redef class AVarReassignExpr
1004 redef fun accept_typing
(v
)
1006 var variable
= self.variable
1007 assert variable
!= null
1009 var readtype
= v
.get_variable
(self, variable
)
1010 if readtype
== null then return
1012 read_type
= readtype
1014 var writetype
= variable
.declared_type
1015 if writetype
== null then return
1017 var rettype
= self.resolve_reassignment
(v
, readtype
, writetype
)
1019 v
.set_variable
(self, variable
, rettype
)
1021 self.is_typed
= rettype
!= null
1026 redef class AContinueExpr
1027 redef fun accept_typing
(v
)
1029 var nexpr
= self.n_expr
1030 if nexpr
!= null then
1033 self.is_typed
= true
1037 redef class ABreakExpr
1038 redef fun accept_typing
(v
)
1040 var nexpr
= self.n_expr
1041 if nexpr
!= null then
1044 self.is_typed
= true
1048 redef class AReturnExpr
1049 redef fun accept_typing
(v
)
1051 var nexpr
= self.n_expr
1053 var mpropdef
= v
.mpropdef
1054 if mpropdef
isa MMethodDef then
1055 ret_type
= mpropdef
.msignature
.return_mtype
1056 else if mpropdef
isa MAttributeDef then
1057 ret_type
= mpropdef
.static_mtype
1061 if nexpr
!= null then
1062 if ret_type
!= null then
1063 v
.visit_expr_subtype
(nexpr
, ret_type
)
1066 v
.error
(nexpr
, "Error: `return` with value in a procedure.")
1069 else if ret_type
!= null then
1070 v
.error
(self, "Error: `return` without value in a function.")
1073 self.is_typed
= true
1077 redef class AAbortExpr
1078 redef fun accept_typing
(v
)
1080 self.is_typed
= true
1085 redef fun accept_typing
(v
)
1087 v
.visit_expr_bool
(n_expr
)
1089 v
.visit_stmt
(n_then
)
1090 v
.visit_stmt
(n_else
)
1092 self.is_typed
= true
1094 if n_then
!= null and n_else
== null then
1095 self.mtype
= n_then
.mtype
1100 redef class AIfexprExpr
1101 redef fun accept_typing
(v
)
1103 v
.visit_expr_bool
(n_expr
)
1105 var t1
= v
.visit_expr
(n_then
)
1106 var t2
= v
.visit_expr
(n_else
)
1108 if t1
== null or t2
== null then
1112 var t
= v
.merge_types
(self, [t1
, t2
])
1114 v
.error
(self, "Type Error: ambiguous type `{t1}` vs `{t2}`.")
1121 redef fun accept_typing
(v
)
1123 v
.visit_stmt
(n_block
)
1124 self.is_typed
= true
1128 redef class AWhileExpr
1129 redef fun accept_typing
(v
)
1132 v
.visit_expr_bool
(n_expr
)
1133 v
.visit_stmt
(n_block
)
1134 self.is_typed
= true
1138 redef class ALoopExpr
1139 redef fun accept_typing
(v
)
1142 v
.visit_stmt
(n_block
)
1143 self.is_typed
= true
1147 redef class AForExpr
1148 redef fun accept_typing
(v
)
1152 for g
in n_groups
do
1153 var mtype
= v
.visit_expr
(g
.n_expr
)
1154 if mtype
== null then return
1155 g
.do_type_iterator
(v
, mtype
)
1156 if g
.is_broken
then is_broken
= true
1159 v
.visit_stmt
(n_block
)
1161 self.mtype
= n_block
.mtype
1162 self.is_typed
= true
1166 redef class AForGroup
1167 var coltype
: nullable MClassType
1169 var method_iterator
: nullable CallSite
1170 var method_is_ok
: nullable CallSite
1171 var method_item
: nullable CallSite
1172 var method_next
: nullable CallSite
1173 var method_key
: nullable CallSite
1174 var method_finish
: nullable CallSite
1176 var method_lt
: nullable CallSite
1177 var method_successor
: nullable CallSite
1179 private fun do_type_iterator
(v
: TypeVisitor, mtype
: MType)
1181 if mtype
isa MNullType then
1182 v
.error
(self, "Type Error: `for` cannot iterate over `null`.")
1187 var objcla
= v
.get_mclass
(self, "Object")
1188 if objcla
== null then return
1190 # check iterator method
1191 var itdef
= v
.get_method
(self, mtype
, "iterator", n_expr
isa ASelfExpr)
1192 if itdef
== null then
1193 v
.error
(self, "Type Error: `for` expects a type providing an `iterator` method, got `{mtype}`.")
1196 self.method_iterator
= itdef
1198 # check that iterator return something
1199 var ittype
= itdef
.msignature
.return_mtype
1200 if ittype
== null then
1201 v
.error
(self, "Type Error: `for` expects the method `iterator` to return an `Iterator` or `MapIterator` type.")
1206 var colit_cla
= v
.try_get_mclass
(self, "Iterator")
1207 var mapit_cla
= v
.try_get_mclass
(self, "MapIterator")
1211 if colit_cla
!= null and v
.is_subtype
(ittype
, colit_cla
.get_mtype
([objcla
.mclass_type
.as_nullable
])) then
1213 var coltype
= ittype
.supertype_to
(v
.mmodule
, v
.anchor
, colit_cla
)
1214 var variables
= self.variables
1215 if variables
.length
!= 1 then
1216 v
.error
(self, "Type Error: `for` expects only one variable when using `Iterator`.")
1218 variables
.first
.declared_type
= coltype
.arguments
.first
1223 if mapit_cla
!= null and v
.is_subtype
(ittype
, mapit_cla
.get_mtype
([objcla
.mclass_type
.as_nullable
, objcla
.mclass_type
.as_nullable
])) then
1225 var coltype
= ittype
.supertype_to
(v
.mmodule
, v
.anchor
, mapit_cla
)
1226 var variables
= self.variables
1227 if variables
.length
!= 2 then
1228 v
.error
(self, "Type Error: `for` expects two variables when using `MapIterator`.")
1230 variables
[0].declared_type
= coltype
.arguments
[0]
1231 variables
[1].declared_type
= coltype
.arguments
[1]
1236 if not is_col
and not is_map
then
1237 v
.error
(self, "Type Error: `for` expects the method `iterator` to return an `Iterator` or `MapIterator` type.")
1241 # anchor formal and virtual types
1242 if mtype
.need_anchor
then mtype
= v
.anchor_to
(mtype
)
1244 mtype
= mtype
.undecorate
1245 self.coltype
= mtype
.as(MClassType)
1247 # get methods is_ok, next, item
1248 var ikdef
= v
.get_method
(self, ittype
, "is_ok", false)
1249 if ikdef
== null then
1250 v
.error
(self, "Type Error: `for` expects a method `is_ok` in type `{ittype}`.")
1253 self.method_is_ok
= ikdef
1255 var itemdef
= v
.get_method
(self, ittype
, "item", false)
1256 if itemdef
== null then
1257 v
.error
(self, "Type Error: `for` expects a method `item` in type `{ittype}`.")
1260 self.method_item
= itemdef
1262 var nextdef
= v
.get_method
(self, ittype
, "next", false)
1263 if nextdef
== null then
1264 v
.error
(self, "Type Error: `for` expects a method `next` in type {ittype}.")
1267 self.method_next
= nextdef
1269 self.method_finish
= v
.try_get_method
(self, ittype
, "finish", false)
1272 var keydef
= v
.get_method
(self, ittype
, "key", false)
1273 if keydef
== null then
1274 v
.error
(self, "Type Error: `for` expects a method `key` in type `{ittype}`.")
1277 self.method_key
= keydef
1280 if self.variables
.length
== 1 and n_expr
isa ARangeExpr then
1281 var variable
= variables
.first
1282 var vtype
= variable
.declared_type
.as(not null)
1284 if n_expr
isa AOrangeExpr then
1285 self.method_lt
= v
.get_method
(self, vtype
, "<", false)
1287 self.method_lt
= v
.get_method
(self, vtype
, "<=", false)
1290 self.method_successor
= v
.get_method
(self, vtype
, "successor", false)
1295 redef class AWithExpr
1296 var method_start
: nullable CallSite
1297 var method_finish
: nullable CallSite
1299 redef fun accept_typing
(v
: TypeVisitor)
1301 var mtype
= v
.visit_expr
(n_expr
)
1302 if mtype
== null then return
1304 method_start
= v
.get_method
(self, mtype
, "start", n_expr
isa ASelfExpr)
1305 method_finish
= v
.get_method
(self, mtype
, "finish", n_expr
isa ASelfExpr)
1307 v
.visit_stmt
(n_block
)
1308 self.mtype
= n_block
.mtype
1309 self.is_typed
= true
1313 redef class AAssertExpr
1314 redef fun accept_typing
(v
)
1316 v
.visit_expr_bool
(n_expr
)
1318 v
.visit_stmt
(n_else
)
1319 self.is_typed
= true
1324 redef fun accept_typing
(v
)
1326 v
.visit_expr_bool
(n_expr
)
1327 v
.visit_expr_bool
(n_expr2
)
1328 self.mtype
= v
.type_bool
(self)
1332 redef class AImpliesExpr
1333 redef fun accept_typing
(v
)
1335 v
.visit_expr_bool
(n_expr
)
1336 v
.visit_expr_bool
(n_expr2
)
1337 self.mtype
= v
.type_bool
(self)
1341 redef class AAndExpr
1342 redef fun accept_typing
(v
)
1344 v
.visit_expr_bool
(n_expr
)
1345 v
.visit_expr_bool
(n_expr2
)
1346 self.mtype
= v
.type_bool
(self)
1351 redef class ANotExpr
1352 redef fun accept_typing
(v
)
1354 v
.visit_expr_bool
(n_expr
)
1355 self.mtype
= v
.type_bool
(self)
1359 redef class AOrElseExpr
1360 redef fun accept_typing
(v
)
1362 var t1
= v
.visit_expr
(n_expr
)
1363 var t2
= v
.visit_expr
(n_expr2
)
1365 if t1
== null or t2
== null then
1369 if t1
isa MNullType then
1372 else if v
.can_be_null
(t1
) then
1376 var t
= v
.merge_types
(self, [t1
, t2
])
1378 var c
= v
.get_mclass
(self, "Object")
1379 if c
== null then return # forward error
1381 if v
.can_be_null
(t2
) then
1384 #v.error(self, "Type Error: ambiguous type {t1} vs {t2}")
1389 redef fun accept_post_typing
(v
)
1391 var t1
= n_expr
.mtype
1395 v
.check_can_be_null
(n_expr
, t1
)
1400 redef class ATrueExpr
1401 redef fun accept_typing
(v
)
1403 self.mtype
= v
.type_bool
(self)
1407 redef class AFalseExpr
1408 redef fun accept_typing
(v
)
1410 self.mtype
= v
.type_bool
(self)
1414 redef class AIntegerExpr
1415 redef fun accept_typing
(v
)
1417 var mclass
: nullable MClass = null
1418 if value
isa Byte then
1419 mclass
= v
.get_mclass
(self, "Byte")
1420 else if value
isa Int then
1421 mclass
= v
.get_mclass
(self, "Int")
1422 else if value
isa Int8 then
1423 mclass
= v
.get_mclass
(self, "Int8")
1424 else if value
isa Int16 then
1425 mclass
= v
.get_mclass
(self, "Int16")
1426 else if value
isa UInt16 then
1427 mclass
= v
.get_mclass
(self, "UInt16")
1428 else if value
isa Int32 then
1429 mclass
= v
.get_mclass
(self, "Int32")
1430 else if value
isa UInt32 then
1431 mclass
= v
.get_mclass
(self, "UInt32")
1433 if mclass
== null then return # Forward error
1434 self.mtype
= mclass
.mclass_type
1438 redef class AFloatExpr
1439 redef fun accept_typing
(v
)
1441 var mclass
= v
.get_mclass
(self, "Float")
1442 if mclass
== null then return # Forward error
1443 self.mtype
= mclass
.mclass_type
1447 redef class ACharExpr
1448 redef fun accept_typing
(v
)
1450 var mclass
= v
.get_mclass
(self, "Char")
1451 if mclass
== null then return # Forward error
1452 self.mtype
= mclass
.mclass_type
1456 redef class AStringFormExpr
1457 redef fun accept_typing
(v
)
1459 var mclass
= v
.get_mclass
(self, "String")
1460 if mclass
== null then return # Forward error
1461 self.mtype
= mclass
.mclass_type
1465 redef class ASuperstringExpr
1466 redef fun accept_typing
(v
)
1468 var mclass
= v
.get_mclass
(self, "String")
1469 if mclass
== null then return # Forward error
1470 self.mtype
= mclass
.mclass_type
1471 var objclass
= v
.get_mclass
(self, "Object")
1472 if objclass
== null then return # Forward error
1473 var objtype
= objclass
.mclass_type
1474 for nexpr
in self.n_exprs
do
1475 v
.visit_expr_subtype
(nexpr
, objtype
)
1480 redef class AArrayExpr
1481 # The `with_capacity` method on Array
1482 var with_capacity_callsite
: nullable CallSite
1484 # The `push` method on arrays
1485 var push_callsite
: nullable CallSite
1487 # The element of each type
1488 var element_mtype
: nullable MType
1490 # Set that `self` is a part of comprehension array `na`
1491 # If `self` is a `for`, or a `if`, then `set_comprehension` is recursively applied.
1492 private fun set_comprehension
(n
: nullable AExpr)
1496 else if n
isa AForExpr then
1497 set_comprehension
(n
.n_block
)
1498 else if n
isa AIfExpr then
1499 set_comprehension
(n
.n_then
)
1500 set_comprehension
(n
.n_else
)
1503 n
.comprehension
= self
1506 redef fun accept_typing
(v
)
1508 var mtype
: nullable MType = null
1509 var ntype
= self.n_type
1510 if ntype
!= null then
1511 mtype
= v
.resolve_mtype
(ntype
)
1512 if mtype
== null then return # Skip error
1514 var mtypes
= new Array[nullable MType]
1516 for e
in self.n_exprs
do
1517 var t
= v
.visit_expr
(e
)
1521 set_comprehension
(e
)
1522 if mtype
!= null then
1523 if v
.check_subtype
(e
, t
, mtype
, false) == null then return # Forward error
1524 if t
== mtype
then useless
= true
1529 if mtype
== null then
1530 # Ensure monotony for type adaptation on loops
1531 if self.element_mtype
!= null then mtypes
.add
self.element_mtype
1532 mtype
= v
.merge_types
(self, mtypes
)
1534 if mtype
== null or mtype
isa MNullType then
1535 v
.error
(self, "Type Error: ambiguous array type {mtypes.join(" ")}")
1539 assert ntype
!= null
1540 v
.modelbuilder
.warning
(ntype
, "useless-type", "Warning: useless type declaration `{mtype}` in literal Array since it can be inferred from the elements type.")
1543 self.element_mtype
= mtype
1545 var mclass
= v
.get_mclass
(self, "Array")
1546 if mclass
== null then return # Forward error
1547 var array_mtype
= mclass
.get_mtype
([mtype
])
1549 with_capacity_callsite
= v
.get_method
(self, array_mtype
, "with_capacity", false)
1550 push_callsite
= v
.get_method
(self, array_mtype
, "push", false)
1552 self.mtype
= array_mtype
1556 redef class ARangeExpr
1557 var init_callsite
: nullable CallSite
1559 redef fun accept_typing
(v
)
1561 var discrete_class
= v
.get_mclass
(self, "Discrete")
1562 if discrete_class
== null then return # Forward error
1563 var discrete_type
= discrete_class
.intro
.bound_mtype
1564 var t1
= v
.visit_expr_subtype
(self.n_expr
, discrete_type
)
1565 var t2
= v
.visit_expr_subtype
(self.n_expr2
, discrete_type
)
1566 if t1
== null or t2
== null then return
1567 var mclass
= v
.get_mclass
(self, "Range")
1568 if mclass
== null then return # Forward error
1570 if v
.is_subtype
(t1
, t2
) then
1571 mtype
= mclass
.get_mtype
([t2
])
1572 else if v
.is_subtype
(t2
, t1
) then
1573 mtype
= mclass
.get_mtype
([t1
])
1575 v
.error
(self, "Type Error: cannot create range: `{t1}` vs `{t2}`.")
1581 # get the constructor
1583 if self isa ACrangeExpr then
1584 callsite
= v
.get_method
(self, mtype
, "init", false)
1585 else if self isa AOrangeExpr then
1586 callsite
= v
.get_method
(self, mtype
, "without_last", false)
1590 init_callsite
= callsite
1594 redef class ANullExpr
1595 redef fun accept_typing
(v
)
1597 self.mtype
= v
.mmodule
.model
.null_type
1601 redef class AIsaExpr
1602 # The static type to cast to.
1603 # (different from the static type of the expression that is `Bool`).
1604 var cast_type
: nullable MType
1605 redef fun accept_typing
(v
)
1607 v
.visit_expr
(n_expr
)
1609 var mtype
= v
.resolve_mtype
(n_type
)
1611 self.cast_type
= mtype
1613 var variable
= self.n_expr
.its_variable
1614 if variable
!= null then
1615 #var orig = self.n_expr.mtype
1616 #var from = if orig != null then orig.to_s else "invalid"
1617 #var to = if mtype != null then mtype.to_s else "invalid"
1618 #debug("adapt {variable}: {from} -> {to}")
1619 self.after_flow_context
.when_true
.set_var
(v
, variable
, mtype
)
1622 self.mtype
= v
.type_bool
(self)
1625 redef fun accept_post_typing
(v
)
1627 v
.check_expr_cast
(self, self.n_expr
, self.n_type
)
1631 redef class AAsCastExpr
1632 redef fun accept_typing
(v
)
1634 v
.visit_expr
(n_expr
)
1636 self.mtype
= v
.resolve_mtype
(n_type
)
1639 redef fun accept_post_typing
(v
)
1641 v
.check_expr_cast
(self, self.n_expr
, self.n_type
)
1645 redef class AAsNotnullExpr
1646 redef fun accept_typing
(v
)
1648 var mtype
= v
.visit_expr
(self.n_expr
)
1649 if mtype
== null then return # Forward error
1651 if mtype
isa MNullType then
1652 v
.error
(self, "Type Error: `as(not null)` on `null`.")
1656 if v
.can_be_null
(mtype
) then
1657 mtype
= mtype
.as_notnull
1663 redef fun accept_post_typing
(v
)
1665 var mtype
= n_expr
.mtype
1666 if mtype
== null then return
1667 v
.check_can_be_null
(n_expr
, mtype
)
1671 redef class AParExpr
1672 redef fun accept_typing
(v
)
1674 self.mtype
= v
.visit_expr
(self.n_expr
)
1678 redef class AOnceExpr
1679 redef fun accept_typing
(v
)
1681 self.mtype
= v
.visit_expr
(self.n_expr
)
1685 redef class ASelfExpr
1686 redef var its_variable
: nullable Variable
1687 redef fun accept_typing
(v
)
1689 if v
.is_toplevel_context
and not self isa AImplicitSelfExpr then
1690 v
.error
(self, "Error: `self` cannot be used in top-level method.")
1692 var variable
= v
.selfvariable
1693 self.its_variable
= variable
1694 self.mtype
= v
.get_variable
(self, variable
)
1698 redef class AImplicitSelfExpr
1699 # Is the implicit receiver `sys`?
1701 # By default, the implicit receiver is `self`.
1702 # But when there is not method for `self`, `sys` is used as a fall-back.
1703 # Is this case this flag is set to `true`.
1707 ## MESSAGE SENDING AND PROPERTY
1709 redef class ASendExpr
1710 # The property invoked by the send.
1711 var callsite
: nullable CallSite
1713 redef fun accept_typing
(v
)
1715 var nrecv
= self.n_expr
1716 var recvtype
= v
.visit_expr
(nrecv
)
1717 var name
= self.property_name
1718 var node
= self.property_node
1720 if recvtype
== null then return # Forward error
1723 var unsafe_type
= v
.anchor_to
(recvtype
)
1724 var mproperty
= v
.try_get_mproperty_by_name2
(node
, unsafe_type
, name
)
1725 if mproperty
== null and nrecv
isa AImplicitSelfExpr then
1726 # Special fall-back search in `sys` when noting found in the implicit receiver.
1727 var sysclass
= v
.try_get_mclass
(node
, "Sys")
1728 if sysclass
!= null then
1729 var systype
= sysclass
.mclass_type
1730 mproperty
= v
.try_get_mproperty_by_name2
(node
, systype
, name
)
1731 if mproperty
!= null then
1732 callsite
= v
.get_method
(node
, systype
, name
, false)
1733 if callsite
== null then return # Forward error
1734 # Update information, we are looking at `sys` now, not `self`
1736 nrecv
.its_variable
= null
1737 nrecv
.mtype
= systype
1742 if callsite
== null then
1743 # If still nothing, just exit
1744 callsite
= v
.get_method
(node
, recvtype
, name
, nrecv
isa ASelfExpr)
1745 if callsite
== null then return
1748 self.callsite
= callsite
1749 var msignature
= callsite
.msignature
1751 var args
= compute_raw_arguments
1753 callsite
.check_signature
(v
, node
, args
)
1755 if callsite
.mproperty
.is_init
then
1756 var vmpropdef
= v
.mpropdef
1757 if not (vmpropdef
isa MMethodDef and vmpropdef
.mproperty
.is_init
) then
1758 v
.error
(node
, "Error: an `init` can only be called from another `init`.")
1760 if vmpropdef
isa MMethodDef and vmpropdef
.mproperty
.is_root_init
and not callsite
.mproperty
.is_root_init
then
1761 v
.error
(node
, "Error: `{vmpropdef}` cannot call a factory `{callsite.mproperty}`.")
1765 var ret
= msignature
.return_mtype
1769 self.is_typed
= true
1773 # The name of the property
1774 # Each subclass simply provide the correct name.
1775 private fun property_name
: String is abstract
1777 # The node identifying the name (id, operator, etc) for messages.
1779 # Is `self` by default
1780 private fun property_node
: ANode do return self
1782 # An array of all arguments (excluding self)
1783 fun raw_arguments
: Array[AExpr] do return compute_raw_arguments
1785 private fun compute_raw_arguments
: Array[AExpr] is abstract
1788 redef class ABinopExpr
1789 redef fun compute_raw_arguments
do return [n_expr2
]
1790 redef fun property_name
do return operator
1791 redef fun property_node
do return n_op
1794 redef class AEqFormExpr
1795 redef fun accept_typing
(v
)
1801 redef fun accept_post_typing
(v
)
1803 var mtype
= n_expr
.mtype
1804 var mtype2
= n_expr2
.mtype
1806 if mtype
== null or mtype2
== null then return
1808 if not mtype2
isa MNullType then return
1810 v
.check_can_be_null
(n_expr
, mtype
)
1814 redef class AUnaryopExpr
1815 redef fun property_name
do return "unary {operator}"
1816 redef fun compute_raw_arguments
do return new Array[AExpr]
1820 redef class ACallExpr
1821 redef fun property_name
do return n_qid
.n_id
.text
1822 redef fun property_node
do return n_qid
1823 redef fun compute_raw_arguments
do return n_args
.to_a
1826 redef class ACallAssignExpr
1827 redef fun property_name
do return n_qid
.n_id
.text
+ "="
1828 redef fun property_node
do return n_qid
1829 redef fun compute_raw_arguments
1831 var res
= n_args
.to_a
1837 redef class ABraExpr
1838 redef fun property_name
do return "[]"
1839 redef fun compute_raw_arguments
do return n_args
.to_a
1842 redef class ABraAssignExpr
1843 redef fun property_name
do return "[]="
1844 redef fun compute_raw_arguments
1846 var res
= n_args
.to_a
1852 redef class ASendReassignFormExpr
1853 # The property invoked for the writing
1854 var write_callsite
: nullable CallSite
1856 redef fun accept_typing
(v
)
1858 var recvtype
= v
.visit_expr
(self.n_expr
)
1859 var name
= self.property_name
1860 var node
= self.property_node
1862 if recvtype
== null then return # Forward error
1864 var for_self
= self.n_expr
isa ASelfExpr
1865 var callsite
= v
.get_method
(node
, recvtype
, name
, for_self
)
1867 if callsite
== null then return
1868 self.callsite
= callsite
1870 var args
= compute_raw_arguments
1872 callsite
.check_signature
(v
, node
, args
)
1874 var readtype
= callsite
.msignature
.return_mtype
1875 if readtype
== null then
1876 v
.error
(node
, "Error: `{name}` is not a function.")
1880 var wcallsite
= v
.get_method
(node
, recvtype
, name
+ "=", self.n_expr
isa ASelfExpr)
1881 if wcallsite
== null then return
1882 self.write_callsite
= wcallsite
1884 var wtype
= self.resolve_reassignment
(v
, readtype
, wcallsite
.msignature
.mparameters
.last
.mtype
)
1885 if wtype
== null then return
1887 args
= args
.to_a
# duplicate so raw_arguments keeps only the getter args
1888 args
.add
(self.n_value
)
1889 wcallsite
.check_signature
(v
, node
, args
)
1891 self.is_typed
= true
1895 redef class ACallReassignExpr
1896 redef fun property_name
do return n_qid
.n_id
.text
1897 redef fun property_node
do return n_qid
.n_id
1898 redef fun compute_raw_arguments
do return n_args
.to_a
1901 redef class ABraReassignExpr
1902 redef fun property_name
do return "[]"
1903 redef fun compute_raw_arguments
do return n_args
.to_a
1906 redef class AInitExpr
1907 redef fun property_name
do return "init"
1908 redef fun property_node
do return n_kwinit
1909 redef fun compute_raw_arguments
do return n_args
.to_a
1913 fun to_a
: Array[AExpr] do return self.n_exprs
.to_a
1918 redef class ASuperExpr
1919 # The method to call if the super is in fact a 'super init call'
1920 # Note: if the super is a normal call-next-method, then this attribute is null
1921 var callsite
: nullable CallSite
1923 # The method to call is the super is a standard `call-next-method` super-call
1924 # Note: if the super is a special super-init-call, then this attribute is null
1925 var mpropdef
: nullable MMethodDef
1927 redef fun accept_typing
(v
)
1929 var anchor
= v
.anchor
1930 assert anchor
!= null
1931 var recvtype
= v
.get_variable
(self, v
.selfvariable
)
1932 assert recvtype
!= null
1933 var mproperty
= v
.mpropdef
.mproperty
1934 if not mproperty
isa MMethod then
1935 v
.error
(self, "Error: `super` only usable in a `method`.")
1938 var superprops
= mproperty
.lookup_super_definitions
(v
.mmodule
, anchor
)
1939 if superprops
.length
== 0 then
1940 if mproperty
.is_init
and v
.mpropdef
.is_intro
then
1941 process_superinit
(v
)
1944 v
.error
(self, "Error: no super method to call for `{mproperty}`.")
1947 # FIXME: covariance of return type in linear extension?
1948 var superprop
= superprops
.first
1950 var msignature
= superprop
.msignature
.as(not null)
1951 msignature
= v
.resolve_for
(msignature
, recvtype
, true).as(MSignature)
1952 var args
= self.n_args
.to_a
1953 if args
.length
> 0 then
1954 signaturemap
= v
.check_signature
(self, args
, mproperty
, msignature
)
1956 self.mtype
= msignature
.return_mtype
1957 self.is_typed
= true
1958 v
.mpropdef
.has_supercall
= true
1959 mpropdef
= v
.mpropdef
.as(MMethodDef)
1962 # The mapping used on the call to associate arguments to parameters.
1963 # If null then no specific association is required.
1964 var signaturemap
: nullable SignatureMap
1966 private fun process_superinit
(v
: TypeVisitor)
1968 var anchor
= v
.anchor
1969 assert anchor
!= null
1970 var recvtype
= v
.get_variable
(self, v
.selfvariable
)
1971 assert recvtype
!= null
1972 var mpropdef
= v
.mpropdef
1973 assert mpropdef
isa MMethodDef
1974 var mproperty
= mpropdef
.mproperty
1975 var superprop
: nullable MMethodDef = null
1976 for msupertype
in mpropdef
.mclassdef
.supertypes
do
1977 msupertype
= msupertype
.anchor_to
(v
.mmodule
, anchor
)
1978 var errcount
= v
.modelbuilder
.toolcontext
.error_count
1979 var candidate
= v
.try_get_mproperty_by_name2
(self, msupertype
, mproperty
.name
).as(nullable MMethod)
1980 if candidate
== null then
1981 if v
.modelbuilder
.toolcontext
.error_count
> errcount
then return # Forward error
1982 continue # Try next super-class
1984 if superprop
!= null and candidate
.is_root_init
then
1987 if superprop
!= null and superprop
.mproperty
!= candidate
and not superprop
.mproperty
.is_root_init
then
1988 v
.error
(self, "Error: conflicting super constructor to call for `{mproperty}`: `{candidate.full_name}`, `{superprop.mproperty.full_name}`")
1991 var candidatedefs
= candidate
.lookup_definitions
(v
.mmodule
, anchor
)
1992 if superprop
!= null and superprop
.mproperty
== candidate
then
1993 if superprop
== candidatedefs
.first
then continue
1994 candidatedefs
.add
(superprop
)
1996 if candidatedefs
.length
> 1 then
1997 v
.error
(self, "Error: conflicting property definitions for property `{mproperty}` in `{recvtype}`: {candidatedefs.join(", ")}")
2000 superprop
= candidatedefs
.first
2002 if superprop
== null then
2003 v
.error
(self, "Error: no super method to call for `{mproperty}`.")
2007 var msignature
= superprop
.new_msignature
or else superprop
.msignature
.as(not null)
2008 msignature
= v
.resolve_for
(msignature
, recvtype
, true).as(MSignature)
2010 var callsite
= new CallSite(hot_location
, recvtype
, v
.mmodule
, v
.anchor
, true, superprop
.mproperty
, superprop
, msignature
, false)
2011 self.callsite
= callsite
2013 var args
= self.n_args
.to_a
2014 if args
.length
> 0 then
2015 callsite
.check_signature
(v
, self, args
)
2017 # Check there is at least enough parameters
2018 if mpropdef
.msignature
.arity
< msignature
.arity
then
2019 v
.error
(self, "Error: not enough implicit arguments to pass. Got `{mpropdef.msignature.arity}`, expected at least `{msignature.arity}`. Signature is `{msignature}`.")
2022 # Check that each needed parameter is conform
2024 for sp
in msignature
.mparameters
do
2025 var p
= mpropdef
.msignature
.mparameters
[i
]
2026 if not v
.is_subtype
(p
.mtype
, sp
.mtype
) then
2027 v
.error
(self, "Type Error: expected argument #{i} of type `{sp.mtype}`, got implicit argument `{p.name}` of type `{p.mtype}`. Signature is {msignature}")
2034 self.is_typed
= true
2040 redef class ANewExpr
2041 # The constructor invoked by the new.
2042 var callsite
: nullable CallSite
2044 # The designated type
2045 var recvtype
: nullable MClassType
2047 redef fun accept_typing
(v
)
2049 var recvtype
= v
.resolve_mtype
(self.n_type
)
2050 if recvtype
== null then return
2052 if not recvtype
isa MClassType then
2053 if recvtype
isa MNullableType then
2054 v
.error
(self, "Type Error: cannot instantiate the nullable type `{recvtype}`.")
2056 else if recvtype
isa MFormalType then
2057 v
.error
(self, "Type Error: cannot instantiate the formal type `{recvtype}`.")
2060 v
.error
(self, "Type Error: cannot instantiate the type `{recvtype}`.")
2065 self.recvtype
= recvtype
2066 var kind
= recvtype
.mclass
.kind
2069 var nqid
= self.n_qid
2071 if nqid
!= null then
2072 name
= nqid
.n_id
.text
2078 if name
== "intern" then
2079 if kind
!= concrete_kind
then
2080 v
.error
(self, "Type Error: cannot instantiate {kind} {recvtype}.")
2083 if n_args
.n_exprs
.not_empty
then
2084 v
.error
(n_args
, "Type Error: the intern constructor expects no arguments.")
2088 self.mtype
= recvtype
2092 var callsite
= v
.get_method
(node
, recvtype
, name
, false)
2093 if callsite
== null then return
2095 if not callsite
.mproperty
.is_new
then
2096 if kind
!= concrete_kind
then
2097 v
.error
(self, "Type Error: cannot instantiate {kind} `{recvtype}`.")
2100 self.mtype
= recvtype
2102 self.mtype
= callsite
.msignature
.return_mtype
2103 assert self.mtype
!= null
2106 self.callsite
= callsite
2108 if not callsite
.mproperty
.is_init_for
(recvtype
.mclass
) then
2109 v
.error
(self, "Error: `{name}` is not a constructor.")
2113 var args
= n_args
.to_a
2114 callsite
.check_signature
(v
, node
, args
)
2120 redef class AAttrFormExpr
2121 # The attribute accessed.
2122 var mproperty
: nullable MAttribute
2124 # The static type of the attribute.
2125 var attr_type
: nullable MType
2127 # Resolve the attribute accessed.
2128 private fun resolve_property
(v
: TypeVisitor)
2130 var recvtype
= v
.visit_expr
(self.n_expr
)
2131 if recvtype
== null then return # Skip error
2132 var node
= self.n_id
2133 var name
= node
.text
2134 if recvtype
isa MNullType then
2135 v
.error
(node
, "Error: attribute `{name}` access on `null`.")
2139 var unsafe_type
= v
.anchor_to
(recvtype
)
2140 var mproperty
= v
.try_get_mproperty_by_name2
(node
, unsafe_type
, name
)
2141 if mproperty
== null then
2142 v
.modelbuilder
.error
(node
, "Error: attribute `{name}` does not exist in `{recvtype}`.")
2145 assert mproperty
isa MAttribute
2146 self.mproperty
= mproperty
2148 var mpropdefs
= mproperty
.lookup_definitions
(v
.mmodule
, unsafe_type
)
2149 assert mpropdefs
.length
== 1
2150 var mpropdef
= mpropdefs
.first
2151 var attr_type
= mpropdef
.static_mtype
2152 if attr_type
== null then return # skip error
2153 attr_type
= v
.resolve_for
(attr_type
, recvtype
, self.n_expr
isa ASelfExpr)
2154 self.attr_type
= attr_type
2158 redef class AAttrExpr
2159 redef fun accept_typing
(v
)
2161 self.resolve_property
(v
)
2162 self.mtype
= self.attr_type
2167 redef class AAttrAssignExpr
2168 redef fun accept_typing
(v
)
2170 self.resolve_property
(v
)
2171 var mtype
= self.attr_type
2173 v
.visit_expr_subtype
(self.n_value
, mtype
)
2174 self.is_typed
= mtype
!= null
2178 redef class AAttrReassignExpr
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 rettype
= self.resolve_reassignment
(v
, mtype
, mtype
)
2187 self.is_typed
= rettype
!= null
2191 redef class AIssetAttrExpr
2192 redef fun accept_typing
(v
)
2194 self.resolve_property
(v
)
2195 var mtype
= self.attr_type
2196 if mtype
== null then return # Skip error
2198 var recvtype
= self.n_expr
.mtype
.as(not null)
2199 var bound
= v
.resolve_for
(mtype
, recvtype
, false)
2200 if bound
isa MNullableType then
2201 v
.error
(n_id
, "Type Error: `isset` on a nullable attribute.")
2203 self.mtype
= v
.type_bool
(self)
2207 redef class AVarargExpr
2208 redef fun accept_typing
(v
)
2210 # This kind of pseudo-expression can be only processed trough a signature
2211 # See `check_signature`
2212 # Other cases are a syntax error.
2213 v
.error
(self, "Syntax Error: unexpected `...`.")
2219 redef class ADebugTypeExpr
2220 redef fun accept_typing
(v
)
2222 var expr
= v
.visit_expr
(self.n_expr
)
2223 if expr
== null then return
2224 var unsafe
= v
.anchor_to
(expr
)
2225 var ntype
= self.n_type
2226 var mtype
= v
.resolve_mtype
(ntype
)
2227 if mtype
!= null and mtype
!= expr
then
2228 var umtype
= v
.anchor_to
(mtype
)
2229 v
.modelbuilder
.warning
(self, "debug", "Found type {expr} (-> {unsafe}), expected {mtype} (-> {umtype})")
2231 self.is_typed
= true