# Current knowledge about variables names and types
readable writable attr _variable_ctx: VariableContext
+ # Non-bypassable knowledge about variables names and types
+ readable writable attr _base_variable_ctx: VariableContext
+
# Current knowledge about escapable blocks
readable writable attr _escapable_ctx: EscapableContext = new EscapableContext(self)
redef meth accept_typing(v)
do
v.variable_ctx = new RootVariableContext(v, self)
+ v.base_variable_ctx = v.variable_ctx
_self_var = v.self_var
super
end
v.variable_ctx.add(variable)
var old_var_ctx = v.variable_ctx
+ var old_base_var_ctx = v.base_variable_ctx
+ v.base_variable_ctx = v.variable_ctx
v.variable_ctx = v.variable_ctx.sub(self)
_escapable = new EscapableClosure(self, variable.closure, null)
old_var_ctx.merge(v.variable_ctx)
v.variable_ctx = old_var_ctx
+ v.base_variable_ctx = old_base_var_ctx
v.escapable_ctx.pop
end
end
end
# Merge 'then' and 'else' contexts
- old_var_ctx.merge2(then_var_ctx, v.variable_ctx)
+ old_var_ctx.merge2(then_var_ctx, v.variable_ctx, v.base_variable_ctx)
v.variable_ctx = old_var_ctx
_is_typed = true
end
_escapable = new EscapableBlock(self)
v.escapable_ctx.push(_escapable)
var old_var_ctx = v.variable_ctx
+ var old_base_var_ctx = v.base_variable_ctx
+ v.base_variable_ctx = v.variable_ctx
v.variable_ctx = v.variable_ctx.sub(self)
super
v.check_conform_expr(n_expr, v.type_bool)
v.variable_ctx = old_var_ctx
+ v.base_variable_ctx = old_base_var_ctx
v.escapable_ctx.pop
_is_typed = true
end
v.escapable_ctx.push(_escapable)
var old_var_ctx = v.variable_ctx
+ var old_base_var_ctx = v.base_variable_ctx
+ v.base_variable_ctx = v.variable_ctx
v.variable_ctx = v.variable_ctx.sub(self)
var va = new AutoVariable(n_id.to_symbol, self)
variable = va
# pop context
v.variable_ctx = old_var_ctx
+ v.base_variable_ctx = old_base_var_ctx
v.escapable_ctx.pop
_is_typed = true
end
do
v.variable_ctx.mark_is_set(variable)
var t = v.variable_ctx.stype(variable)
- if v.check_conform_expr(n_value, variable.stype) then
- # Fall back to base type if current type does not match
- if not n_value.stype < t then
- v.variable_ctx.stype(variable) = variable.stype
- end
- end
+
+ # Check the base type
+ var btype = v.base_variable_ctx.stype(variable)
+ if not v.check_conform_expr(n_value, btype) then return
+
+ # Bypasse cast if then current type does not match
+ if not n_value.stype < t then v.variable_ctx.stype(variable) = btype
+
_is_typed = true
end
end
var t = v.variable_ctx.stype(variable)
var t2 = do_rvalue_typing(v, t)
if t2 == null then return
- if v.check_conform(self, t2, variable.stype) then
- # Fall back to base type if current type does not match
- if not t2 < t then
- v.variable_ctx.stype(variable) = variable.stype
- end
- end
+
+ # Check the base type
+ var btype = v.base_variable_ctx.stype(variable)
+ if not v.check_conform(n_value, t2, btype) then return
+
+ # Bypasse cast if then current type does not match
+ if not t2 < t then v.variable_ctx.stype(variable) = btype
+
_is_typed = true
end
end
closure = esc.closure
var old_var_ctx = v.variable_ctx
+ var old_base_var_ctx = v.base_variable_ctx
+ v.base_variable_ctx = v.variable_ctx
v.variable_ctx = v.variable_ctx.sub(self)
variables = new Array[AutoVariable]
for i in [0..n_id.length[ do
end
end
v.variable_ctx = old_var_ctx
+ v.base_variable_ctx = old_base_var_ctx
end
end
--- /dev/null
+# This file is part of NIT ( http://www.nitlanguage.org ).
+#
+# Copyright 2009 Jean Privat <jean@pryen.org>
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import kernel
+
+class A
+ init do end
+end
+
+class B
+special A
+ meth foo(i: Int) do i.output
+ init do end
+end
+
+meth maybe: Bool do return true
+
+var a: A = new B
+
+assert a isa B
+a.foo(1)
+if maybe then
+ a = new A
+else
+ a = new A
+end
+#alt1#a.foo(1)
+
+a = new B
+assert a isa B
+a.foo(2)
+if maybe then
+else
+ a = new A
+end
+#alt2#a.foo(2)
+
+a = new B
+assert a isa B
+a.foo(3)
+if maybe then
+ a = new A
+else
+end
+#alt3#a.foo(3)
+
+a = new B
+assert a isa B
+a.foo(4)
+if maybe then
+else
+end
+a.foo(4)
+
+a = new B
+assert a isa B
+a.foo(5)
+if maybe then
+ a = new A
+end
+#alt4#a.foo(5)
+
+a = new B
+assert a isa B
+a.foo(6)
+if maybe then
+end
+a.foo(6)
+
+a = new B
+assert a isa B
+a.foo(7)
+while not maybe do
+ #alt5#a = new A
+end
+a.foo(7)
+
+a = new B
+assert a isa B
+a.foo(8)
+while not maybe do
+end
+a.foo(8)
+