import modelize
import local_var_init
+import literal
redef class ToolContext
var typing_phase: Phase = new TypingPhase(self, [flow_phase, modelize_property_phase, local_var_init_phase])
# The module of the analysis
# Used to correctly query the model
- var mmodule: MModule
+ var mmodule: MModule is noinit
# The static type of the receiver
# Mainly used for type tests and type resolutions
- var anchor: nullable MClassType = null
+ var anchor: MClassType is noinit
# The analyzed mclassdef
- var mclassdef: nullable MClassDef = null
+ var mclassdef: MClassDef is noinit
# The analyzed property
- var mpropdef: nullable MPropDef
+ var mpropdef: MPropDef
var selfvariable = new Variable("self")
init
do
var mpropdef = self.mpropdef
+ var mclassdef = mpropdef.mclassdef
+ mmodule = mclassdef.mmodule
+ self.mclassdef = mclassdef
+ self.anchor = mclassdef.bound_mtype
- if mpropdef != null then
- self.mpropdef = mpropdef
- var mclassdef = mpropdef.mclassdef
- self.mclassdef = mclassdef
- self.anchor = mclassdef.bound_mtype
-
- var mclass = mclassdef.mclass
+ var mclass = mclassdef.mclass
- var selfvariable = new Variable("self")
- self.selfvariable = selfvariable
- selfvariable.declared_type = mclass.mclass_type
+ var selfvariable = new Variable("self")
+ self.selfvariable = selfvariable
+ selfvariable.declared_type = mclass.mclass_type
- var mprop = mpropdef.mproperty
- if mprop isa MMethod and mprop.is_new then
- is_toplevel_context = true
- end
+ var mprop = mpropdef.mproperty
+ if mprop isa MMethod and mprop.is_new then
+ is_toplevel_context = true
end
end
fun anchor_to(mtype: MType): MType
do
- var anchor = anchor
- if anchor == null then
- assert not mtype.need_anchor
- return mtype
- end
return mtype.anchor_to(mmodule, anchor)
end
end
# Check that `sub` is a subtype of `sup`.
- # If `sub` is not a valid suptype, then display an error on `node` an return null.
- # If `sub` is a safe subtype of `sup` then return `sub`.
- # If `sub` is an unsafe subtype (ie an implicit cast is required), then return `sup`.
+ # If `sub` is not a valid suptype, then display an error on `node` and return `null`.
+ # If `sub` is a safe subtype of `sup`, then return `sub`.
+ # If `sub` is an unsafe subtype (i.e., an implicit cast is required), then return `sup`.
#
# The point of the return type is to determinate the usable type on an expression when `autocast` is true:
# If the suptype is safe, then the return type is the one on the expression typed by `sub`.
#node.debug("Unsafe typing: expected {sup}, got {sub}")
return sup
end
+ if sup isa MErrorType then return null # Skip error
if sub.need_anchor then
var u = anchor_to(sub)
self.modelbuilder.error(node, "Type Error: expected `{sup}`, got `{sub}: {u}`.")
end
return null # forward error
end
- self.error(nexpr, "Error: expected an expression.")
+ var more_message = null
+ var p = nexpr.parent
+ if p != null then more_message = p.bad_expr_message(nexpr)
+ if more_message == null then more_message = "" else more_message = " " + more_message
+ self.error(nexpr, "Error: expected an expression{more_message}.")
return null
end
return self.visit_expr_subtype(nexpr, self.type_bool(nexpr))
end
-
- fun visit_expr_cast(node: ANode, nexpr: AExpr, ntype: AType): nullable MType
+ fun check_expr_cast(node: ANode, nexpr: AExpr, ntype: AType): nullable MType
do
- var sub = visit_expr(nexpr)
+ var sub = nexpr.mtype
if sub == null then return null # Forward error
- var sup = self.resolve_mtype(ntype)
+ var sup = ntype.mtype
if sup == null then return null # Forward error
if sup == sub then
# Else return true.
fun check_can_be_null(anode: ANode, mtype: MType): Bool
do
+ if mtype isa MNullType then
+ modelbuilder.warning(anode, "useless-null-test", "Warning: expression is always `null`.")
+ return true
+ end
if can_be_null(mtype) then return true
if mtype isa MFormalType then
if not mtype2 isa MNullType then return
# Check of useless null
- if not check_can_be_null(anode.n_expr, mtype) then return
+ if not can_be_null(mtype) then return
if mtype isa MNullType then
# Because of type adaptation, we cannot just stop here
fun resolve_mtype(node: AType): nullable MType
do
- return self.modelbuilder.resolve_mtype(mmodule, mclassdef, node)
+ return self.modelbuilder.resolve_mtype(mclassdef, node)
end
fun try_get_mclass(node: ANode, name: String): nullable MClass
return mclass.mclass_type
end
- fun get_method(node: ANode, recvtype: MType, name: String, recv_is_self: Bool): nullable CallSite
+ # Construction of a specific callsite according to the current context.
+ # Three entry points exist to create a callsite based on knowledge.
+ # The `build_callsite_by_name` is a top entry point, the method find the mpropdefs to call by the name of this.
+ # see `build_callsite_by_property` and `build_callsite_by_propdef` for more detail.
+ # If you already know the mpropdef to call use directly the `get_method_by_propdef` method
+ # If you just know the mproperty use the `build_callsite_by_property` method to display error if no `mpropdef` is found in the context
+ fun build_callsite_by_name(node: ANode, recvtype: MType, name: String, recv_is_self: Bool): nullable CallSite
do
var unsafe_type = self.anchor_to(recvtype)
#debug("recv: {recvtype} (aka {unsafe_type})")
if recvtype isa MNullType then
- # `null` only accepts some methods of object.
- if name == "==" or name == "!=" or name == "is_same_instance" then
- var objclass = get_mclass(node, "Object")
- if objclass == null then return null # Forward error
- unsafe_type = objclass.mclass_type
- else
- self.error(node, "Error: method `{name}` called on `null`.")
- return null
- end
+ var objclass = get_mclass(node, "Object")
+ if objclass == null then return null # Forward error
+ unsafe_type = objclass.mclass_type
end
var mproperty = self.try_get_mproperty_by_name2(node, unsafe_type, name)
assert mproperty isa MMethod
+ return build_callsite_by_property(node, recvtype, mproperty, recv_is_self)
+ end
+
+ # The `build_callsite_by_property` finds the mpropdefs to call by the `MMethod`.
+ # If the mpropdef is found in the context it builds a new `Callsite`.
+ fun build_callsite_by_property(node: ANode, recvtype: MType, mproperty: MMethod, recv_is_self: Bool): nullable CallSite
+ do
+ var unsafe_type = self.anchor_to(recvtype)
+
+ if recvtype isa MNullType then
+ var objclass = get_mclass(node, "Object")
+ if objclass == null then return null # Forward error
+ unsafe_type = objclass.mclass_type
+ end
+ # `null` only accepts some methods of object.
+ if recvtype isa MNullType and not mproperty.is_null_safe then
+ self.error(node, "Error: method `{mproperty.name}` called on `null`.")
+ return null
+ else if unsafe_type isa MNullableType and not mproperty.is_null_safe then
+ modelbuilder.advice(node, "call-on-nullable", "Warning: method call on a nullable receiver `{recvtype}`.")
+ end
+
if is_toplevel_context and recv_is_self and not mproperty.is_toplevel then
- error(node, "Error: `{name}` is not a top-level method, thus need a receiver.")
+ error(node, "Error: `{mproperty.name}` is not a top-level method, thus need a receiver.")
end
if not recv_is_self and mproperty.is_toplevel then
- error(node, "Error: cannot call `{name}`, a top-level method, with a receiver.")
+ error(node, "Error: cannot call `{mproperty.name}`, a top-level method, with a receiver.")
end
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
- self.modelbuilder.error(node, "Error: method `{name}` is protected and can only accessed by `self`.")
+ self.modelbuilder.error(node, "Error: method `{mproperty.name}` is protected and can only accessed by `self`.")
return null
end
if info != null and self.mpropdef.mproperty.deprecation == null then
var mdoc = info.mdoc
if mdoc != null then
- self.modelbuilder.warning(node, "deprecated-method", "Deprecation Warning: method `{name}` is deprecated: {mdoc.content.first}")
+ self.modelbuilder.warning(node, "deprecated-method", "Deprecation Warning: method `{mproperty.name}` is deprecated: {mdoc.content.first}")
else
- self.modelbuilder.warning(node, "deprecated-method", "Deprecation Warning: method `{name}` is deprecated.")
+ self.modelbuilder.warning(node, "deprecated-method", "Deprecation Warning: method `{mproperty.name}` is deprecated.")
end
end
var propdefs = mproperty.lookup_definitions(self.mmodule, unsafe_type)
var mpropdef
if propdefs.length == 0 then
- self.modelbuilder.error(node, "Type Error: no definition found for property `{name}` in `{unsafe_type}`.")
- return null
+ self.modelbuilder.error(node, "Type Error: no definition found for property `{mproperty.name}` in `{unsafe_type}`.")
+ abort
+ #return null
else if propdefs.length == 1 then
mpropdef = propdefs.first
else
- self.modelbuilder.warning(node, "property-conflict", "Warning: conflicting property definitions for property `{name}` in `{unsafe_type}`: {propdefs.join(" ")}")
+ self.modelbuilder.warning(node, "property-conflict", "Warning: conflicting property definitions for property `{mproperty.name}` in `{unsafe_type}`: {propdefs.join(" ")}")
mpropdef = mproperty.intro
end
+ return build_callsite_by_propdef(node, recvtype, mpropdef, recv_is_self)
+ end
+ # The `build_callsite_by_propdef` builds the callsite directly with the `mprodef` passed in argument.
+ fun build_callsite_by_propdef(node: ANode, recvtype: MType, mpropdef: MMethodDef, recv_is_self: Bool): nullable CallSite
+ do
var msignature = mpropdef.new_msignature or else mpropdef.msignature
if msignature == null then return null # skip error
msignature = resolve_for(msignature, recvtype, recv_is_self).as(MSignature)
end
end
- var callsite = new CallSite(node, recvtype, mmodule, anchor, recv_is_self, mproperty, mpropdef, msignature, erasure_cast)
+ var callsite = new CallSite(node.hot_location, recvtype, mmodule, anchor, recv_is_self, mpropdef.mproperty, mpropdef, msignature, erasure_cast)
return callsite
end
- fun try_get_method(node: ANode, recvtype: MType, name: String, recv_is_self: Bool): nullable CallSite
+ fun try_build_callsite_by_name(node: ANode, recvtype: MType, name: String, recv_is_self: Bool): nullable CallSite
do
var unsafe_type = self.anchor_to(recvtype)
var mproperty = self.try_get_mproperty_by_name2(node, unsafe_type, name)
if mproperty == null then return null
- return get_method(node, recvtype, name, recv_is_self)
+ return build_callsite_by_name(node, recvtype, name, recv_is_self)
end
-
# Visit the expressions of args and check their conformity with the corresponding type in signature
# The point of this method is to handle varargs correctly
# Note: The signature must be correctly adapted
return null
end
else if args.length != msignature.arity then
- if msignature.arity == msignature.min_arity then
- modelbuilder.error(node, "Error: expected {msignature.arity} argument(s) for `{mproperty}{msignature}`; got {args.length}. See introduction at `{mproperty.full_name}`.")
- return null
- end
+ # Too much argument
if args.length > msignature.arity then
- modelbuilder.error(node, "Error: expected at most {msignature.arity} argument(s) for `{mproperty}{msignature}`; got {args.length}. See introduction at `{mproperty.full_name}`.")
- return null
- end
- if args.length < msignature.min_arity then
- modelbuilder.error(node, "Error: expected at least {msignature.min_arity} argument(s) for `{mproperty}{msignature}`; got {args.length}. See introduction at `{mproperty.full_name}`.")
+ modelbuilder.error(node, "Error: expected {msignature.arity} argument(s) for `{mproperty}{msignature}`; got {args.length}. See introduction at `{mproperty.full_name}`.")
return null
end
+ # Other cases are managed later
end
#debug("CALL {unsafe_type}.{msignature}")
# Associate each parameter to a position in the arguments
var map = new SignatureMap
- var setted = args.length - msignature.min_arity
+ # Special case for the isolated last argument
+ # TODO: reify this method characteristics (where? the param, the signature, the method?)
+ var last_is_padded = mproperty.name.chars.last == '='
+ var nbargs = args.length
+ if last_is_padded then
+ nbargs -= 1
+ assert not args.last isa ANamedargExpr
+ map.map[msignature.arity - 1] = args.length - 1
+ self.visit_expr_subtype(args.last, msignature.mparameters.last.mtype)
+ end
+
+ # First, handle named arguments
+ for i in [0..args.length[ do
+ var e = args[i]
+ if not e isa ANamedargExpr then continue
+ var name = e.n_id.text
+ var param = msignature.mparameter_by_name(name)
+ if param == null then
+ modelbuilder.error(e.n_id, "Error: no parameter `{name}` for `{mproperty}{msignature}`.")
+ return null
+ end
+ var idx = msignature.mparameters.index_of(param)
+ var prev = map.map.get_or_null(idx)
+ if prev != null then
+ modelbuilder.error(e, "Error: parameter `{name}` already associated with argument #{prev} for `{mproperty}{msignature}`.")
+ return null
+ end
+ map.map[idx] = i
+ e.mtype = self.visit_expr_subtype(e.n_expr, param.mtype)
+ end
+
+ # Number of minimum mandatory remaining parameters
+ var min_arity = 0
+
+ # Second, associate remaining parameters
var vararg_decl = args.length - msignature.arity
var j = 0
for i in [0..msignature.arity[ do
+ # Skip parameters associated by name
+ if map.map.has_key(i) then continue
+
var param = msignature.mparameters[i]
- if param.is_default then
- if setted > 0 then
- setted -= 1
- else
- continue
+
+ # Search the next free argument: skip named arguments since they are already associated
+ while j < nbargs and args[j] isa ANamedargExpr do j += 1
+ if j >= nbargs then
+ if not param.mtype isa MNullableType then
+ min_arity = j + 1
end
+ j += 1
+ continue
end
var arg = args[j]
map.map[i] = j
continue # skip the vararg
end
- var paramtype = param.mtype
- self.visit_expr_subtype(arg, paramtype)
+ if not param.is_vararg then
+ var paramtype = param.mtype
+ self.visit_expr_subtype(arg, paramtype)
+ else
+ check_one_vararg(arg, param)
+ end
end
+
+ if min_arity > 0 then
+ if last_is_padded then min_arity += 1
+ if min_arity < msignature.arity then
+ modelbuilder.error(node, "Error: expected at least {min_arity} argument(s) for `{mproperty}{msignature}`; got {args.length}. See introduction at `{mproperty.full_name}`.")
+ else
+ modelbuilder.error(node, "Error: expected {min_arity} argument(s) for `{mproperty}{msignature}`; got {args.length}. See introduction at `{mproperty.full_name}`.")
+ end
+ return null
+ end
+
+ # Third, check varargs
if vararg_rank >= 0 then
var paramtype = msignature.mparameters[vararg_rank].mtype
var first = args[vararg_rank]
if vararg_decl == 0 then
- var mclass = get_mclass(node, "Array")
- if mclass == null then return null # Forward error
- var array_mtype = mclass.get_mtype([paramtype])
- if first isa AVarargExpr then
- self.visit_expr_subtype(first.n_expr, array_mtype)
- first.mtype = first.n_expr.mtype
- else
- # only one vararg, maybe `...` was forgot, so be gentle!
- var t = visit_expr(first)
- if t == null then return null # Forward error
- if not is_subtype(t, paramtype) and is_subtype(t, array_mtype) then
- # Not acceptable but could be a `...`
- error(first, "Type Error: expected `{paramtype}`, got `{t}`. Is an ellipsis `...` missing on the argument?")
- return null
- end
- # Standard valid vararg, finish the job
- map.vararg_decl = 1
- self.visit_expr_subtype(first, paramtype)
- end
+ if not check_one_vararg(first, msignature.mparameters[vararg_rank]) then return null
else
- map.vararg_decl = vararg_decl + 1
+ first.vararg_decl = vararg_decl + 1
for i in [vararg_rank..vararg_rank+vararg_decl] do
self.visit_expr_subtype(args[i], paramtype)
end
return map
end
+ # Check an expression as a single vararg.
+ # The main point of the method if to handle the case of reversed vararg (see `AVarargExpr`)
+ fun check_one_vararg(arg: AExpr, param: MParameter): Bool
+ do
+ var paramtype = param.mtype
+ var mclass = get_mclass(arg, "Array")
+ if mclass == null then return false # Forward error
+ var array_mtype = mclass.get_mtype([paramtype])
+ if arg isa AVarargExpr then
+ self.visit_expr_subtype(arg.n_expr, array_mtype)
+ arg.mtype = arg.n_expr.mtype
+ else
+ # only one vararg, maybe `...` was forgot, so be gentle!
+ var t = visit_expr(arg)
+ if t == null then return false # Forward error
+ if not is_subtype(t, paramtype) and is_subtype(t, array_mtype) then
+ # Not acceptable but could be a `...`
+ error(arg, "Type Error: expected `{paramtype}`, got `{t}`. Is an ellipsis `...` missing on the argument?")
+ return false
+ end
+ # Standard valid vararg, finish the job
+ arg.vararg_decl = 1
+ self.visit_expr_subtype(arg, paramtype)
+ end
+ return true
+ end
+
fun error(node: ANode, message: String)
do
- self.modelbuilder.toolcontext.error(node.hot_location, message)
+ self.modelbuilder.error(node, message)
end
fun get_variable(node: AExpr, variable: Variable): nullable MType
return mtypes.first
else
var res = merge_types(node,mtypes)
- if res == null then res = variable.declared_type
+ if res == null then
+ res = variable.declared_type
+ # Try to fallback to a non-null version
+ if res != null and can_be_null(res) then do
+ for t in mtypes do
+ if t != null and can_be_null(t) then break label
+ end
+ res = res.as_notnull
+ end label
+ end
return res
end
end
flow.set_var(self, variable, mtype)
end
+ # Find the exact representable most specific common super-type in `col`.
+ #
+ # Try to find the most specific common type that is a super-type of each types
+ # in `col`.
+ # In most cases, the result is simply the most general type in `col`.
+ # If nullables types are involved, then the nullable information is correctly preserved.
+ # If incomparable super-types exists in `col`, them no solution is given and the `null`
+ # value is returned (since union types are non representable in Nit)
+ #
+ # The `null` values in `col` are ignored, nulltypes (MNullType) are considered.
+ #
+ # Returns the `null` value if:
+ #
+ # * `col` is empty
+ # * `col` only have null values
+ # * there is a conflict
+ #
+ # Example (with a diamond A,B,C,D):
+ #
+ # * merge(A,B,C) -> A, because A is the most general type in {A,B,C}
+ # * merge(C,B) -> null, there is conflict, because `B or C` cannot be represented
+ # * merge(A,nullable B) -> nullable A, because A is the most general type and
+ # the nullable information is preserved
fun merge_types(node: ANode, col: Array[nullable MType]): nullable MType
do
if col.length == 1 then return col.first
#self.modelbuilder.warning(node, "Type Error: {col.length} conflicting types: <{col.join(", ")}>")
return null
end
+
+ # Find a most general common subtype between `type1` and `type2`.
+ #
+ # Find the most general type that is a subtype of `type2` and, if possible, a subtype of `type1`.
+ # Basically, this return the most specific type between `type1` and `type2`.
+ # If nullable types are involved, the information is correctly preserved.
+ # If `type1` and `type2` are incomparable then `type2` is preferred (since intersection types
+ # are not representable in Nit).
+ #
+ # The `null` value is returned if both `type1` and `type2` are null.
+ #
+ # Examples (with diamond A,B,C,D):
+ #
+ # * intersect_types(A,B) -> B, because B is a subtype of A
+ # * intersect_types(B,A) -> B, because B is a subtype of A
+ # * intersect_types(B,C) -> C, B and C are incomparable,
+ # `type2` is then preferred (`B and C` cannot be represented)
+ # * intersect_types(nullable B,A) -> B, because B<:A and the non-null information is preserved
+ # * intersect_types(B,nullable C) -> C, `type2` is preferred and the non-null information is preserved
+ fun intersect_types(node: ANode, type1, type2: nullable MType): nullable MType
+ do
+ if type1 == null then return type2
+ if type2 == null then return type1
+
+ if not can_be_null(type2) or not can_be_null(type1) then
+ type1 = type1.as_notnull
+ type2 = type2.as_notnull
+ end
+
+ var res
+ if is_subtype(type1, type2) then
+ res = type1
+ else
+ res = type2
+ end
+ return res
+ end
+
+ # Find a most general type that is a subtype of `type1` but not one of `type2`.
+ #
+ # Basically, this returns `type1`-`type2` but since there is no substraction type
+ # in Nit this just returns `type1` most of the case.
+ #
+ # The few other cases are if `type2` is a super-type and if some nullable information
+ # is present.
+ #
+ # The `null` value is returned if `type1` is null.
+ #
+ # Examples (with diamond A,B,C,D):
+ #
+ # * diff_types(A,B) -> A, because the notB cannot be represented
+ # * diff_types(B,A) -> None (absurd type), because B<:A
+ # * diff_types(nullable A, nullable B) -> A, because null is removed
+ # * diff_types(nullable B, A) -> Null, because anything but null is removed
+ fun diff_types(node: ANode, type1, type2: nullable MType): nullable MType
+ do
+ if type1 == null then return null
+ if type2 == null then return type1
+
+ # if t1 <: t2 then t1-t2 = bottom
+ if is_subtype(type1, type2) then
+ return modelbuilder.model.null_type.as_notnull
+ end
+
+ # else if t1 <: nullable t2 then t1-t2 = nulltype
+ if is_subtype(type1, type2.as_nullable) then
+ return modelbuilder.model.null_type
+ end
+
+ # else t2 can be null and type2 must accept null then null is excluded in t1
+ if can_be_null(type1) and (type2 isa MNullableType or type2 isa MNullType) then
+ return type1.as_notnull
+ end
+
+ return type1
+ end
end
# Mapping between parameters and arguments in a call.
class SignatureMap
# Associate a parameter to an argument
var map = new ArrayMap[Int, Int]
-
- # The length of the vararg sequence
- # 0 if no vararg or if reverse vararg (cf `AVarargExpr`)
- var vararg_decl: Int = 0
end
# A specific method call site with its associated informations.
class CallSite
- # The associated node for location
- var node: ANode
+ super MEntity
+
+ redef var location
# The static type of the receiver (possibly unresolved)
var recv: MType
# If null then no specific association is required.
var signaturemap: nullable SignatureMap = null
- private fun check_signature(v: TypeVisitor, args: Array[AExpr]): Bool
+ private fun check_signature(v: TypeVisitor, node: ANode, args: Array[AExpr]): Bool
do
- var map = v.check_signature(self.node, args, self.mproperty, self.msignature)
+ var map = v.check_signature(node, args, self.mproperty, self.msignature)
signaturemap = map
+ if map == null then is_broken = true
return map == null
end
+
+ # Information about the callsite to display on a node
+ fun dump_info(v: ASTDump): String do
+ return "{recv}.{mpropdef}{msignature}"
+ end
+
+ redef fun mdoc_or_fallback do return mproperty.intro.mdoc
end
redef class Variable
# The declared type of the variable
- var declared_type: nullable MType
+ var declared_type: nullable MType = null is writable
# Was the variable type-adapted?
# This is used to speedup type retrieval while it remains `false`
redef class AMethPropdef
redef fun do_typing(modelbuilder: ModelBuilder)
do
- var nblock = self.n_block
- if nblock == null then return
-
var mpropdef = self.mpropdef
if mpropdef == null then return # skip error
- var v = new TypeVisitor(modelbuilder, mpropdef.mclassdef.mmodule, mpropdef)
+ var v = new TypeVisitor(modelbuilder, mpropdef)
self.selfvariable = v.selfvariable
var mmethoddef = self.mpropdef.as(not null)
variable.declared_type = mtype
end
+ var nblock = self.n_block
+ if nblock == null then return
+
loop
v.dirty = false
v.visit_stmt(nblock)
if not v.has_loop or not v.dirty then break
end
+ var post_visitor = new PostTypingVisitor(v)
+ post_visitor.enter_visit(self)
+
if not nblock.after_flow_context.is_unreachable and msignature.return_mtype != null then
# We reach the end of the function without having a return, it is bad
v.error(self, "Error: reached end of function; expected `return` with a value.")
end
end
+private class PostTypingVisitor
+ super Visitor
+ var type_visitor: TypeVisitor
+ redef fun visit(n) do
+ n.visit_all(self)
+ n.accept_post_typing(type_visitor)
+ if n isa AExpr and n.mtype == null and not n.is_typed then
+ n.is_broken = true
+ end
+ end
+end
+
+redef class ANode
+ private fun accept_post_typing(v: TypeVisitor) do end
+
+ # An additional information message to explain the role of a child expression.
+ #
+ # The point of the method is to allow some kind of double dispatch so the parent
+ # choose how to describe its children.
+ private fun bad_expr_message(child: AExpr): nullable String do return null
+end
+
redef class AAttrPropdef
redef fun do_typing(modelbuilder: ModelBuilder)
do
if not has_value then return
- var mpropdef = self.mpropdef
- if mpropdef == null then return # skip error
+ var mpropdef = self.mreadpropdef
+ if mpropdef == null or mpropdef.msignature == null then return # skip error
- var v = new TypeVisitor(modelbuilder, mpropdef.mclassdef.mmodule, mpropdef)
+ var v = new TypeVisitor(modelbuilder, mpropdef)
self.selfvariable = v.selfvariable
var nexpr = self.n_expr
if nexpr != null then
- var mtype = self.mpropdef.static_mtype
+ var mtype = self.mtype
v.visit_expr_subtype(nexpr, mtype)
end
var nblock = self.n_block
# The result of the evaluation of `self` must be
# stored inside the designated array (there is an implicit `push`)
var comprehension: nullable AArrayExpr = null
+
+ # It indicates the number of arguments collected as a vararg.
+ #
+ # When 0, the argument is used as is, without transformation.
+ # When 1, the argument is transformed into an singleton array.
+ # Above 1, the arguments and the next ones are transformed into a common array.
+ #
+ # This attribute is meaning less on expressions not used as attributes.
+ var vararg_decl: Int = 0
+
+ redef fun dump_info(v) do
+ var res = super
+ var mtype = self.mtype
+ if mtype != null then
+ res += v.yellow(":{mtype}")
+ end
+ var ict = self.implicit_cast_to
+ if ict != null then
+ res += v.yellow("(.as({ict}))")
+ end
+ return res
+ end
end
redef class ABlockExpr
self.read_type = readtype
- var callsite = v.get_method(self.n_assign_op, readtype, reassign_name, false)
+ var callsite = v.build_callsite_by_name(self.n_assign_op, readtype, reassign_name, false)
if callsite == null then return null # Skip error
self.reassign_callsite = callsite
v.set_variable(self, variable, rettype)
- self.is_typed = true
+ self.is_typed = rettype != null
end
end
-
redef class AContinueExpr
redef fun accept_typing(v)
do
else
v.visit_expr(nexpr)
v.error(nexpr, "Error: `return` with value in a procedure.")
+ return
end
else if ret_type != null then
v.error(self, "Error: `return` without value in a function.")
+ return
end
self.is_typed = true
end
redef fun accept_typing(v)
do
v.visit_stmt(n_block)
+ v.visit_stmt(n_catch)
self.is_typed = true
end
end
end
redef class AForExpr
+ redef fun accept_typing(v)
+ do
+ v.has_loop = true
+
+ for g in n_groups do
+ var mtype = v.visit_expr(g.n_expr)
+ if mtype == null then return
+ g.do_type_iterator(v, mtype)
+ if g.is_broken then is_broken = true
+ end
+
+ v.visit_stmt(n_block)
+
+ self.mtype = n_block.mtype
+ self.is_typed = true
+ end
+end
+
+redef class AForGroup
var coltype: nullable MClassType
var method_iterator: nullable CallSite
if objcla == null then return
# check iterator method
- var itdef = v.get_method(self, mtype, "iterator", n_expr isa ASelfExpr)
+ var itdef = v.build_callsite_by_name(self, mtype, "iterator", n_expr isa ASelfExpr)
if itdef == null then
v.error(self, "Type Error: `for` expects a type providing an `iterator` method, got `{mtype}`.")
return
self.coltype = mtype.as(MClassType)
# get methods is_ok, next, item
- var ikdef = v.get_method(self, ittype, "is_ok", false)
+ var ikdef = v.build_callsite_by_name(self, ittype, "is_ok", false)
if ikdef == null then
v.error(self, "Type Error: `for` expects a method `is_ok` in type `{ittype}`.")
return
end
self.method_is_ok = ikdef
- var itemdef = v.get_method(self, ittype, "item", false)
+ var itemdef = v.build_callsite_by_name(self, ittype, "item", false)
if itemdef == null then
v.error(self, "Type Error: `for` expects a method `item` in type `{ittype}`.")
return
end
self.method_item = itemdef
- var nextdef = v.get_method(self, ittype, "next", false)
+ var nextdef = v.build_callsite_by_name(self, ittype, "next", false)
if nextdef == null then
v.error(self, "Type Error: `for` expects a method `next` in type {ittype}.")
return
end
self.method_next = nextdef
- self.method_finish = v.try_get_method(self, ittype, "finish", false)
+ self.method_finish = v.try_build_callsite_by_name(self, ittype, "finish", false)
if is_map then
- var keydef = v.get_method(self, ittype, "key", false)
+ var keydef = v.build_callsite_by_name(self, ittype, "key", false)
if keydef == null then
v.error(self, "Type Error: `for` expects a method `key` in type `{ittype}`.")
return
var vtype = variable.declared_type.as(not null)
if n_expr isa AOrangeExpr then
- self.method_lt = v.get_method(self, vtype, "<", false)
+ self.method_lt = v.build_callsite_by_name(self, vtype, "<", false)
else
- self.method_lt = v.get_method(self, vtype, "<=", false)
+ self.method_lt = v.build_callsite_by_name(self, vtype, "<=", false)
end
- self.method_successor = v.get_method(self, vtype, "successor", false)
+ self.method_successor = v.build_callsite_by_name(self, vtype, "successor", false)
end
end
-
- redef fun accept_typing(v)
- do
- v.has_loop = true
- var mtype = v.visit_expr(n_expr)
- if mtype == null then return
-
- self.do_type_iterator(v, mtype)
-
- v.visit_stmt(n_block)
-
- self.mtype = n_block.mtype
- self.is_typed = true
- end
end
redef class AWithExpr
var mtype = v.visit_expr(n_expr)
if mtype == null then return
- method_start = v.get_method(self, mtype, "start", n_expr isa ASelfExpr)
- method_finish = v.get_method(self, mtype, "finish", n_expr isa ASelfExpr)
+ method_start = v.build_callsite_by_name(self, mtype, "start", n_expr isa ASelfExpr)
+ method_finish = v.build_callsite_by_name(self, mtype, "finish", n_expr isa ASelfExpr)
v.visit_stmt(n_block)
self.mtype = n_block.mtype
end
end
-
redef class ANotExpr
redef fun accept_typing(v)
do
end
if t1 isa MNullType then
- v.error(n_expr, "Type Error: `or else` on `null`.")
- else if v.check_can_be_null(n_expr, t1) then
+ self.mtype = t2
+ return
+ else if v.can_be_null(t1) then
t1 = t1.as_notnull
end
end
self.mtype = t
end
+
+ redef fun accept_post_typing(v)
+ do
+ var t1 = n_expr.mtype
+ if t1 == null then
+ return
+ else
+ v.check_can_be_null(n_expr, t1)
+ end
+ end
end
redef class ATrueExpr
end
end
-redef class AIntExpr
+redef class AIntegerExpr
redef fun accept_typing(v)
do
- var mclass = v.get_mclass(self, "Int")
+ var mclass: nullable MClass = null
+ if value isa Byte then
+ mclass = v.get_mclass(self, "Byte")
+ else if value isa Int then
+ mclass = v.get_mclass(self, "Int")
+ else if value isa Int8 then
+ mclass = v.get_mclass(self, "Int8")
+ else if value isa Int16 then
+ mclass = v.get_mclass(self, "Int16")
+ else if value isa UInt16 then
+ mclass = v.get_mclass(self, "UInt16")
+ else if value isa Int32 then
+ mclass = v.get_mclass(self, "Int32")
+ else if value isa UInt32 then
+ mclass = v.get_mclass(self, "UInt32")
+ end
if mclass == null then return # Forward error
self.mtype = mclass.mclass_type
end
end
redef class ACharExpr
- redef fun accept_typing(v)
- do
- var mclass = v.get_mclass(self, "Char")
+ redef fun accept_typing(v) do
+ var mclass: nullable MClass = null
+ if is_code_point then
+ mclass = v.get_mclass(self, "Int")
+ else
+ mclass = v.get_mclass(self, "Char")
+ end
if mclass == null then return # Forward error
self.mtype = mclass.mclass_type
end
end
-redef class AStringFormExpr
- redef fun accept_typing(v)
- do
+redef class AugmentedStringFormExpr
+ super AExpr
+
+ # Text::to_re, used for prefix `re`
+ var to_re: nullable CallSite = null
+ # Regex::ignore_case, used for suffix `i` on `re`
+ var ignore_case: nullable CallSite = null
+ # Regex::newline, used for suffix `m` on `re`
+ var newline: nullable CallSite = null
+ # Regex::extended, used for suffix `b` on `re`
+ var extended: nullable CallSite = null
+ # CString::to_bytes_with_copy, used for prefix `b`
+ var to_bytes_with_copy: nullable CallSite = null
+
+ redef fun accept_typing(v) do
var mclass = v.get_mclass(self, "String")
if mclass == null then return # Forward error
- self.mtype = mclass.mclass_type
+ if is_bytestring then
+ to_bytes_with_copy = v.build_callsite_by_name(self, v.mmodule.c_string_type, "to_bytes_with_copy", false)
+ mclass = v.get_mclass(self, "Bytes")
+ else if is_re then
+ to_re = v.build_callsite_by_name(self, mclass.mclass_type, "to_re", false)
+ for i in suffix.chars do
+ mclass = v.get_mclass(self, "Regex")
+ if mclass == null then
+ v.error(self, "Error: `Regex` class unknown")
+ return
+ end
+ var service = ""
+ if i == 'i' then
+ service = "ignore_case="
+ ignore_case = v.build_callsite_by_name(self, mclass.mclass_type, service, false)
+ else if i == 'm' then
+ service = "newline="
+ newline = v.build_callsite_by_name(self, mclass.mclass_type, service, false)
+ else if i == 'b' then
+ service = "extended="
+ extended = v.build_callsite_by_name(self, mclass.mclass_type, service, false)
+ else
+ v.error(self, "Type Error: Unrecognized suffix {i} in prefixed Regex")
+ abort
+ end
+ end
+ end
+ if mclass == null then return # Forward error
+ mtype = mclass.mclass_type
end
end
redef class ASuperstringExpr
redef fun accept_typing(v)
do
- var mclass = v.get_mclass(self, "String")
- if mclass == null then return # Forward error
- self.mtype = mclass.mclass_type
+ super
var objclass = v.get_mclass(self, "Object")
if objclass == null then return # Forward error
var objtype = objclass.mclass_type
if mclass == null then return # Forward error
var array_mtype = mclass.get_mtype([mtype])
- with_capacity_callsite = v.get_method(self, array_mtype, "with_capacity", false)
- push_callsite = v.get_method(self, array_mtype, "push", false)
+ with_capacity_callsite = v.build_callsite_by_name(self, array_mtype, "with_capacity", false)
+ push_callsite = v.build_callsite_by_name(self, array_mtype, "push", false)
self.mtype = array_mtype
end
# get the constructor
var callsite
if self isa ACrangeExpr then
- callsite = v.get_method(self, mtype, "init", false)
+ callsite = v.build_callsite_by_name(self, mtype, "init", false)
else if self isa AOrangeExpr then
- callsite = v.get_method(self, mtype, "without_last", false)
+ callsite = v.build_callsite_by_name(self, mtype, "without_last", false)
else
abort
end
var cast_type: nullable MType
redef fun accept_typing(v)
do
- var mtype = v.visit_expr_cast(self, self.n_expr, self.n_type)
+ v.visit_expr(n_expr)
+
+ var mtype = v.resolve_mtype(n_type)
+
self.cast_type = mtype
var variable = self.n_expr.its_variable
if variable != null then
- #var orig = self.n_expr.mtype
+ var orig = self.n_expr.mtype
#var from = if orig != null then orig.to_s else "invalid"
#var to = if mtype != null then mtype.to_s else "invalid"
#debug("adapt {variable}: {from} -> {to}")
- self.after_flow_context.when_true.set_var(v, variable, mtype)
+
+ var thentype = v.intersect_types(self, orig, mtype)
+ if thentype != orig then
+ self.after_flow_context.when_true.set_var(v, variable, thentype)
+ #debug "{variable}:{orig or else "?"} isa {mtype or else "?"} -> then {thentype or else "?"}"
+ end
+
+ var elsetype = v.diff_types(self, orig, mtype)
+ if elsetype != orig then
+ self.after_flow_context.when_false.set_var(v, variable, elsetype)
+ #debug "{variable}:{orig or else "?"} isa {mtype or else "?"} -> else {elsetype or else "?"}"
+ end
end
self.mtype = v.type_bool(self)
end
+
+ redef fun accept_post_typing(v)
+ do
+ v.check_expr_cast(self, self.n_expr, self.n_type)
+ end
+
+ redef fun dump_info(v) do
+ var res = super
+ var mtype = self.cast_type
+ if mtype != null then
+ res += v.yellow(".as({mtype})")
+ end
+ return res
+ end
+
end
redef class AAsCastExpr
redef fun accept_typing(v)
do
- self.mtype = v.visit_expr_cast(self, self.n_expr, self.n_type)
+ v.visit_expr(n_expr)
+
+ self.mtype = v.resolve_mtype(n_type)
+ end
+
+ redef fun accept_post_typing(v)
+ do
+ v.check_expr_cast(self, self.n_expr, self.n_type)
end
end
return
end
- if v.check_can_be_null(n_expr, mtype) then
+ if v.can_be_null(mtype) then
mtype = mtype.as_notnull
end
self.mtype = mtype
end
+
+ redef fun accept_post_typing(v)
+ do
+ var mtype = n_expr.mtype
+ if mtype == null then return
+ v.check_can_be_null(n_expr, mtype)
+ end
end
redef class AParExpr
# The property invoked by the send.
var callsite: nullable CallSite
+ # Is self a safe call (with `x?.foo`)?
+ # If so and the receiver is null, then the arguments won't be evaluated
+ # and the call skipped (replaced with null).
+ var is_safe: Bool = false
+
+ redef fun bad_expr_message(child)
+ do
+ if child == self.n_expr then
+ return "to be the receiver of `{self.property_name}`"
+ end
+ return null
+ end
+
redef fun accept_typing(v)
do
var nrecv = self.n_expr
var recvtype = v.visit_expr(nrecv)
+
+ if nrecv isa ASafeExpr then
+ # Has the receiver the form `x?.foo`?
+ # For parsing "reasons" the `?` is in the receiver node, not the call node.
+ is_safe = true
+ end
+
var name = self.property_name
var node = self.property_node
var systype = sysclass.mclass_type
mproperty = v.try_get_mproperty_by_name2(node, systype, name)
if mproperty != null then
- callsite = v.get_method(node, systype, name, false)
+ callsite = v.build_callsite_by_name(node, systype, name, false)
if callsite == null then return # Forward error
# Update information, we are looking at `sys` now, not `self`
nrecv.is_sys = true
end
if callsite == null then
# If still nothing, just exit
- callsite = v.get_method(node, recvtype, name, nrecv isa ASelfExpr)
+ callsite = v.build_callsite_by_name(node, recvtype, name, nrecv isa ASelfExpr)
if callsite == null then return
end
var args = compute_raw_arguments
- callsite.check_signature(v, args)
+ if not self isa ACallrefExpr then
+ callsite.check_signature(v, node, args)
+ end
if callsite.mproperty.is_init then
var vmpropdef = v.mpropdef
var ret = msignature.return_mtype
if ret != null then
+ if is_safe then
+ # A safe receiver makes that the call is not executed and returns null
+ ret = ret.as_nullable
+ end
self.mtype = ret
else
self.is_typed = true
fun raw_arguments: Array[AExpr] do return compute_raw_arguments
private fun compute_raw_arguments: Array[AExpr] is abstract
+
+ redef fun dump_info(v) do
+ var res = super
+ var callsite = self.callsite
+ if callsite != null then
+ res += v.yellow(" call="+callsite.dump_info(v))
+ end
+ return res
+ end
end
redef class ABinopExpr
redef fun property_name do return operator
redef fun property_node do return n_op
end
-redef class AEqExpr
+
+redef class AEqFormExpr
redef fun accept_typing(v)
do
super
v.null_test(self)
end
-end
-redef class ANeExpr
- redef fun accept_typing(v)
+
+ redef fun accept_post_typing(v)
do
- super
- v.null_test(self)
- end
-end
+ var mtype = n_expr.mtype
+ var mtype2 = n_expr2.mtype
-redef class AUplusExpr
- redef fun property_name do return "unary +"
- redef fun compute_raw_arguments do return new Array[AExpr]
+ if mtype == null or mtype2 == null then return
+
+ if mtype == v.type_bool(self) and (n_expr2 isa AFalseExpr or n_expr2 isa ATrueExpr) then
+ v.modelbuilder.warning(self, "useless-truism", "Warning: useless comparison to a Bool literal.")
+ end
+
+ if not mtype2 isa MNullType then return
+
+ v.check_can_be_null(n_expr, mtype)
+ end
end
-redef class AUminusExpr
- redef fun property_name do return "unary -"
+redef class AUnaryopExpr
+ redef fun property_name do return "unary {operator}"
redef fun compute_raw_arguments do return new Array[AExpr]
end
-
redef class ACallExpr
- redef fun property_name do return n_id.text
- redef fun property_node do return n_id
+ redef fun property_name do return n_qid.n_id.text
+ redef fun property_node do return n_qid
redef fun compute_raw_arguments do return n_args.to_a
end
redef class ACallAssignExpr
- redef fun property_name do return n_id.text + "="
- redef fun property_node do return n_id
+ redef fun property_name do return n_qid.n_id.text + "="
+ redef fun property_node do return n_qid
redef fun compute_raw_arguments
do
var res = n_args.to_a
if recvtype == null then return # Forward error
var for_self = self.n_expr isa ASelfExpr
- var callsite = v.get_method(node, recvtype, name, for_self)
+ var callsite = v.build_callsite_by_name(node, recvtype, name, for_self)
if callsite == null then return
self.callsite = callsite
var args = compute_raw_arguments
- callsite.check_signature(v, args)
+ callsite.check_signature(v, node, args)
var readtype = callsite.msignature.return_mtype
if readtype == null then
return
end
- var wcallsite = v.get_method(node, recvtype, name + "=", self.n_expr isa ASelfExpr)
+ var wcallsite = v.build_callsite_by_name(node, recvtype, name + "=", self.n_expr isa ASelfExpr)
if wcallsite == null then return
self.write_callsite = wcallsite
args = args.to_a # duplicate so raw_arguments keeps only the getter args
args.add(self.n_value)
- wcallsite.check_signature(v, args)
+ wcallsite.check_signature(v, node, args)
self.is_typed = true
end
end
redef class ACallReassignExpr
- redef fun property_name do return n_id.text
- redef fun property_node do return n_id
+ redef fun property_name do return n_qid.n_id.text
+ redef fun property_node do return n_qid.n_id
redef fun compute_raw_arguments do return n_args.to_a
end
redef fun compute_raw_arguments do return n_args.to_a
end
+redef class ACallrefExpr
+ redef fun property_name do return n_qid.n_id.text
+ redef fun property_node do return n_qid
+ redef fun compute_raw_arguments do return n_args.to_a
+
+ redef fun accept_typing(v)
+ do
+ super # do the job as if it was a real call
+ var res = callsite.mproperty
+
+ var msignature = callsite.mpropdef.msignature
+ var recv = callsite.recv
+ assert msignature != null
+ var arity = msignature.mparameters.length
+
+ var routine_type_name = "ProcRef"
+ if msignature.return_mtype != null then
+ routine_type_name = "FunRef"
+ end
+
+ var target_routine_class = "{routine_type_name}{arity}"
+ var routine_mclass = v.get_mclass(self, target_routine_class)
+
+ if routine_mclass == null then
+ v.error(self, "Error: missing functional types, try `import functional`")
+ return
+ end
+
+ var types_list = new Array[MType]
+ for param in msignature.mparameters do
+ if param.is_vararg then
+ types_list.push(v.mmodule.array_type(param.mtype))
+ else
+ types_list.push(param.mtype)
+ end
+ end
+ if msignature.return_mtype != null then
+ types_list.push(msignature.return_mtype.as(not null))
+ end
+
+ # Why we need an anchor :
+ #
+ # ~~~~nitish
+ # class A[E]
+ # def toto(x: E) do print "{x}"
+ # end
+ #
+ # var a = new A[Int]
+ # var f = &a.toto # without anchor : ProcRef1[E]
+ # # with anchor : ProcRef[Int]
+ # ~~~~
+ # However, we can only anchor if we can resolve every formal
+ # parameter, here's an example where we can't.
+ # ~~~~nitish
+ # class A[E]
+ # fun bar: A[E] do return self
+ # fun foo: Fun0[A[E]] do return &bar # here we can't anchor
+ # end
+ # var f1 = a1.foo # when this expression will be evaluated,
+ # # `a1` will anchor `&bar` returned by `foo`.
+ # print f1.call
+ # ~~~~
+ var routine_type = routine_mclass.get_mtype(types_list)
+ if not recv.need_anchor then
+ routine_type = routine_type.anchor_to(v.mmodule, recv.as(MClassType))
+ end
+ is_typed = true
+ self.mtype = routine_type
+ end
+end
+
redef class AExprs
fun to_a: Array[AExpr] do return self.n_exprs.to_a
end
redef fun accept_typing(v)
do
var anchor = v.anchor
- assert anchor != null
var recvtype = v.get_variable(self, v.selfvariable)
assert recvtype != null
var mproperty = v.mpropdef.mproperty
private fun process_superinit(v: TypeVisitor)
do
var anchor = v.anchor
- assert anchor != null
var recvtype = v.get_variable(self, v.selfvariable)
assert recvtype != null
var mpropdef = v.mpropdef
var msignature = superprop.new_msignature or else superprop.msignature.as(not null)
msignature = v.resolve_for(msignature, recvtype, true).as(MSignature)
- var callsite = new CallSite(self, recvtype, v.mmodule, v.anchor, true, superprop.mproperty, superprop, msignature, false)
+ var callsite = new CallSite(hot_location, recvtype, v.mmodule, v.anchor, true, superprop.mproperty, superprop, msignature, false)
self.callsite = callsite
var args = self.n_args.to_a
if args.length > 0 then
- callsite.check_signature(v, args)
+ callsite.check_signature(v, self, args)
else
# Check there is at least enough parameters
if mpropdef.msignature.arity < msignature.arity then
self.is_typed = true
end
+
+ redef fun dump_info(v) do
+ var res = super
+ var callsite = self.callsite
+ if callsite != null then
+ res += v.yellow(" super-init="+callsite.dump_info(v))
+ end
+ var mpropdef = self.mpropdef
+ if mpropdef != null then
+ res += v.yellow(" call-next-method="+mpropdef.to_s)
+ end
+ return res
+ end
end
####
var kind = recvtype.mclass.kind
var name: String
- var nid = self.n_id
+ var nqid = self.n_qid
var node: ANode
- if nid != null then
- name = nid.text
- node = nid
+ if nqid != null then
+ name = nqid.n_id.text
+ node = nqid
else
name = "new"
node = self.n_kwnew
return
end
- var callsite = v.get_method(node, recvtype, name, false)
+ var callsite = v.build_callsite_by_name(node, recvtype, name, false)
if callsite == null then return
if not callsite.mproperty.is_new then
end
var args = n_args.to_a
- callsite.check_signature(v, args)
+ callsite.check_signature(v, node, args)
+ end
+
+ redef fun dump_info(v) do
+ var res = super
+ var callsite = self.callsite
+ if callsite != null then
+ res += v.yellow(" call="+callsite.dump_info(v))
+ end
+ return res
end
end
attr_type = v.resolve_for(attr_type, recvtype, self.n_expr isa ASelfExpr)
self.attr_type = attr_type
end
+
+ redef fun dump_info(v) do
+ var res = super
+ var mproperty = self.mproperty
+ var attr_type = self.attr_type
+ if mproperty != null then
+ res += v.yellow(" attr={mproperty}:{attr_type or else "BROKEN"}")
+ end
+ return res
+ end
end
redef class AAttrExpr
end
end
-
redef class AAttrAssignExpr
redef fun accept_typing(v)
do
var mtype = self.attr_type
v.visit_expr_subtype(self.n_value, mtype)
- self.is_typed = true
+ self.is_typed = mtype != null
end
end
var mtype = self.attr_type
if mtype == null then return # Skip error
- self.resolve_reassignment(v, mtype, mtype)
+ var rettype = self.resolve_reassignment(v, mtype, mtype)
- self.is_typed = true
+ self.is_typed = rettype != null
end
end
end
end
+redef class ASafeExpr
+ redef fun accept_typing(v)
+ do
+ var mtype = v.visit_expr(n_expr)
+ if mtype == null then return # Skip error
+
+ if mtype isa MNullType then
+ # While `null?.foo` is semantically well defined and should not execute `foo` and just return `null`,
+ # currently `null.foo` is forbidden so it seems coherent to also forbid `null?.foo`
+ v.modelbuilder.error(self, "Error: safe operator `?` on `null`.")
+ return
+ end
+
+ self.mtype = mtype.as_notnull
+
+ if not v.can_be_null(mtype) then
+ v.modelbuilder.warning(self, "useless-safe", "Warning: useless safe operator `?` on non-nullable value.")
+ return
+ end
+ end
+end
+
redef class AVarargExpr
redef fun accept_typing(v)
do
nitlanguage / nit.git / blobdiff