X-Git-Url: http://nitlanguage.org

diff --git a/src/syntax/mmbuilder.nit b/src/syntax/mmbuilder.nit
index 38dcb8e..2651efe 100644
--- a/src/syntax/mmbuilder.nit
+++ b/src/syntax/mmbuilder.nit
@@ -23,7 +23,7 @@ import syntax_base
 
 # Class specialization hierarchy sorter
 private class CSHSorter
-special AbstractSorter[MMLocalClass]
+	super AbstractSorter[MMLocalClass]
 	redef fun compare(a, b)
 	do
 		return a.cshe.rank <=> b.cshe.rank
@@ -59,7 +59,7 @@ redef class MMSrcModule
 
 		# Compute specialization relation
 		for c in local_classes do
-			if visibility_for(c.global.intro.module) < c.global.visibility_level then
+			if visibility_for(c.global.intro.mmmodule) < c.global.visibility_level then
 				continue
 			end
 			c.compute_super_classes
@@ -84,23 +84,20 @@ redef class MMSrcModule
 		end
 
 		# Check class conformity
-		var mmbv1b = new ClassVerifierVisitor(tc, self)
+		var mmbv1c = new ClassVerifierVisitor(tc, self)
 		for c in classes do
-			c.accept_class_visitor(mmbv1b)
+			c.accept_class_visitor(mmbv1c)
 		end
 		tc.check_errors
 
 		# Property inhritance and introduction
 		var mmbv2 = new PropertyBuilderVisitor(tc, self)
 		for c in classes do
-			# Inherit global properties
-			c.inherit_global_properties
-
 			# Global property introduction and redefinition 
 			c.accept_class_visitor(mmbv2)
 
 			# Default and inherited constructor if needed
-			if c isa MMSrcLocalClass and c.global.intro == c and not c.global.is_universal and not c.global.is_interface then
+			if c isa MMSrcLocalClass and c.global.intro == c and not c.global.is_enum and not c.global.is_interface then
 				c.process_default_constructors(mmbv2)
 			end
 
@@ -114,14 +111,6 @@ redef class MMSrcModule
 			c.accept_properties_visitor(mmbv3)
 		end
 
-		# Check inherited local properties
-		for c in classes do
-			for g in c.global_properties do
-				if visibility_for(g.intro.module) < g.visibility_level then continue
-				var p = c[g]
-			end
-		end
-
 		tc.check_errors
 	end
 
@@ -194,7 +183,7 @@ redef class MMSrcLocalClass
 		var super_inits = new ArraySet[MMLocalProperty]
 		var super_constructors = new ArraySet[MMGlobalProperty]
 		for sc in che.direct_greaters do
-			if sc.global.is_universal or sc.global.is_interface then continue
+			if sc.global.is_enum or sc.global.is_interface then continue
 			for gp in sc.global_properties do
 				if not gp.is_init then continue
 				super_constructors.add(gp)
@@ -322,7 +311,7 @@ end
 
 # Concrete NIT class specialization relation
 class MMSrcAncestor
-special MMAncestor
+	super MMAncestor
 	redef readable var _local_class: MMLocalClass
 
 	init(c: MMLocalClass)
@@ -337,7 +326,7 @@ end
 # * Build the classes and attach them to global classes
 # * Collect generic formal parameters.
 private class ClassBuilderVisitor
-special AbsSyntaxVisitor
+	super AbsSyntaxVisitor
 	# Current class arity
 	readable writable var _local_class_arity: Int = 0
 
@@ -351,7 +340,7 @@ end
 # Another pass visitor for syntax analysis.
 # * Build ancertors (with only class informations not the type one)
 private class ClassSpecializationBuilderVisitor
-special AbsSyntaxVisitor
+	super AbsSyntaxVisitor
 	redef fun visit(n) do n.accept_class_specialization_builder(self)
 	init(tc, m) do super
 end
@@ -359,7 +348,7 @@ end
 # Another pass visitor for syntax analysis.
 # * Compute types in ancestors
 private class ClassAncestorBuilder
-special AbsSyntaxVisitor
+	super AbsSyntaxVisitor
 	redef fun visit(n) do n.accept_class_ancestor_builder(self)
 	init(tc, m) do super
 end
@@ -367,7 +356,7 @@ end
 # Another pass visitor for syntax analysis.
 # * Checks classes in regard to superclasses
 private class ClassVerifierVisitor
-special AbsSyntaxVisitor
+	super AbsSyntaxVisitor
 	redef fun visit(n) do n.accept_class_verifier(self)
 	init(tc, m) do super
 end
@@ -378,7 +367,7 @@ end
 # * Build local properties and attache them to global properties
 # * Attach bound to formal types
 private class PropertyBuilderVisitor
-special AbsSyntaxVisitor
+	super AbsSyntaxVisitor
 	redef fun visit(n) do n.accept_property_builder(self)
 	init(tc, m) do super
 end
@@ -386,7 +375,7 @@ end
 # Another pass pass visitor for syntax analysis.
 # * Check property conformance
 private class PropertyVerifierVisitor
-special AbsSyntaxVisitor
+	super AbsSyntaxVisitor
 
 	# The signature currently build
 	readable writable var _signature_builder: SignatureBuilder
@@ -403,10 +392,10 @@ end
 # Information about a signature currently build
 private class SignatureBuilder
 	# Current visited parameter types
-	readable writable var _params: Array[PParam] = new Array[PParam]
+	readable writable var _params: Array[AParam] = new Array[AParam]
 	
 	# Visited parameters without type information added
-	readable writable var _untyped_params: Array[PParam] = new Array[PParam]
+	readable writable var _untyped_params: Array[AParam] = new Array[AParam]
 
 	# Position of the current star parameter
 	readable writable var _vararg_rank: Int = -1
@@ -423,7 +412,7 @@ end
 
 ###############################################################################
 
-redef class PNode
+redef class ANode
 	private fun accept_class_builder(v: ClassBuilderVisitor) do accept_abs_syntax_visitor(v)
 	private fun accept_class_specialization_builder(v: ClassSpecializationBuilderVisitor) do accept_abs_syntax_visitor(v)
 	private fun accept_class_ancestor_builder(v: ClassAncestorBuilder) do accept_abs_syntax_visitor(v)
@@ -437,48 +426,43 @@ redef class AModule
 	fun import_super_modules(tc: ToolContext, mod: MMSrcModule)
 	do
 		# Import super-modules
-		var module_names_to_import = new Array[Symbol]
-		var module_visibility = new HashMap[Symbol, Int]
-		var no_import: nullable PImport = null
+		var supers = new Array[MMModule]
+		var no_import: nullable AImport = null
 		for i in n_imports do
 			var n = i.module_name
 			if n != null then
-				module_names_to_import.add(n)
-				module_visibility[n] = i.visibility_level
+				var m = tc.get_module(n, mod)
+				supers.add(m)
+				mod.add_super_module(m, i.visibility_level)
 			else
 				no_import = i
 			end
 		end
 		if no_import != null then
-			if not module_names_to_import.is_empty then
+			if not supers.is_empty then
 				tc.error(no_import.location, "Error: Top modules cannot import other modules.")
 			end
-		else if module_names_to_import.is_empty then
+		else if supers.is_empty then
 			var stdname = once "standard".to_symbol
-			module_names_to_import.add(stdname)
-			module_visibility[stdname] = 1
+			var m = tc.get_module(stdname, mod)
+			supers.add(m)
+			mod.add_super_module(m, 1)
 		end
 
-		mod.import_supers_modules(module_names_to_import)
-
-		for mname in module_names_to_import do
-			var level = module_visibility[mname]
-			var m = tc.get_module(mname, mod)
-			mod.add_super_module(m, level)
-		end
+		tc.add_module(mod, supers)
 	end
 end
 
-redef class APackagedecl
+redef class AModuledecl
 	redef fun accept_class_builder(v)
 	do
-		if n_id.to_symbol != v.module.name then
-			v.error(n_id, "Error: Package name missmatch between {v.module.name} and {n_id.to_symbol}")
+		if n_name.n_id.to_symbol != v.mmmodule.name then
+			v.error(n_name.n_id, "Error: Module name missmatch between {v.mmmodule.name} and {n_name.n_id.to_symbol}")
 		end
 	end
 end
 
-redef class PImport
+redef class AImport
 	# Imported module name (or null)
 	fun module_name: nullable Symbol is abstract
 
@@ -488,7 +472,7 @@ end
 redef class AStdImport
 	redef fun module_name
 	do
-		return n_id.to_symbol
+		return n_name.n_id.to_symbol
 	end
 	redef fun visibility_level
 	do
@@ -502,7 +486,7 @@ redef class ANoImport
 	end
 end
 
-redef class PVisibility
+redef class AVisibility
 	# Visibility level
 	fun level: Int is abstract
 end
@@ -520,7 +504,7 @@ redef class AIntrudeVisibility
 end
 
 
-redef class PClassdef
+redef class AClassdef
 	redef fun local_class: MMSrcLocalClass do return _local_class.as(not null)
 	var _local_class: nullable MMSrcLocalClass
 
@@ -536,10 +520,11 @@ redef class PClassdef
 	redef fun accept_class_builder(v)
 	do
 		var local_class: MMSrcLocalClass
-		var mod = v.module
+		var mod = v.mmmodule
 		var local_classes = mod.src_local_classes
 		if (local_classes.has_key(name)) then
 			local_class = local_classes[name]
+			_local_class = local_class
 			if self isa AStdClassdef then
 				# If we are not a special implicit class then rant
 				v.error(self, "Error: A class {name} is already defined at line {local_class.node.location.line_start}.")
@@ -551,15 +536,16 @@ redef class PClassdef
 			n.next_node = self
 		else
 			local_class = new MMSrcLocalClass(mod, name, self, arity)
+			_local_class = local_class
 			local_classes[name] = local_class
 			if not mod.has_global_class_named(name) then
-				local_class.new_global
+				build_class_introduction(v)
 			else
-				local_class.set_global(mod.global_class_named(name))
+				var glob = mod.global_class_named(name)
+				build_class_refinement(v, glob)
 			end
 
 		end
-		_local_class = local_class
 		v.local_class_arity = 0
 		v.formals = local_class.formal_dict
 
@@ -570,6 +556,70 @@ redef class PClassdef
 		v.formals = null
 	end
 
+	fun build_class_introduction(v: AbsSyntaxVisitor)
+	do
+		local_class.new_global
+		var glob = local_class.global
+
+		glob.visibility_level = visibility_level
+		if self isa AStdClassdef then
+			if n_kwredef != null then
+				v.error(self, "Redef error: No class {name} is imported. Remove the redef keyword to define a new class.")
+				return
+			end
+			glob.is_interface = n_classkind.is_interface
+			glob.is_abstract = n_classkind.is_abstract
+			glob.is_enum = n_classkind.is_enum
+		end
+	end
+
+	fun build_class_refinement(v: AbsSyntaxVisitor, glob: MMGlobalClass)
+	do
+		local_class.set_global(glob)
+
+		glob.check_visibility(v, self, v.mmmodule)
+		if self isa AStdClassdef and n_kwredef == null then
+			v.error(self, "Redef error: {name} is an imported class. Add the redef keyword to refine it.")
+			return
+		end
+
+		if glob.intro.arity != _local_class.arity then
+			v.error(self, "Redef error: Formal parameter arity missmatch; got {_local_class.arity}, expected {glob.intro.arity}.")
+		end
+
+		if self isa AStdClassdef and (not glob.is_interface and n_classkind.is_interface or
+			not glob.is_abstract and n_classkind.is_abstract or
+			not glob.is_enum and n_classkind.is_enum)
+		then
+			v.error(self, "Redef error: cannot change kind of class {name}.")
+		end
+	end
+
+	redef fun accept_class_verifier(v)
+	do
+		super
+		var glob = _local_class.global
+		for c in _local_class.cshe.direct_greaters do
+			var cg = c.global
+			if glob.is_interface then
+				if cg.is_enum then
+					v.error(self, "Special error: Interface {name} try to specialise enum class {c.name}.")
+				else if not cg.is_interface then
+					v.error(self, "Special error: Interface {name} try to specialise class {c.name}.")
+				end
+			else if glob.is_enum then
+				if not cg.is_interface and not cg.is_enum then
+					v.error(self, "Special error: Enum class {name} try to specialise class {c.name}.")
+				end
+			else
+				if cg.is_enum then
+					v.error(self, "Special error: Class {name} try to specialise enum class {c.name}.")
+				end
+			end
+
+		end
+	end
+
 	redef fun accept_abs_syntax_visitor(v)
 	do
 		v.local_class = _local_class
@@ -578,17 +628,17 @@ redef class PClassdef
 	end
 end
 
-redef class PClasskind
+redef class AClasskind
 	fun is_interface: Bool do return false
-	fun is_universal: Bool do return false
+	fun is_enum: Bool do return false
 	fun is_abstract: Bool do return false
 end
 
 redef class AInterfaceClasskind
 	redef fun is_interface do return true
 end
-redef class AUniversalClasskind
-	redef fun is_universal do return true
+redef class AEnumClasskind
+	redef fun is_enum do return true
 end
 redef class AAbstractClasskind
 	redef fun is_abstract do return true
@@ -603,62 +653,6 @@ redef class AStdClassdef
 	do
 		return n_formaldefs.length
 	end
-	redef fun accept_class_verifier(v)
-	do
-		super
-		var glob = _local_class.global
-		if glob.intro == _local_class then
-			# Intro
-			glob.visibility_level = visibility_level
-			glob.is_interface = n_classkind.is_interface
-			glob.is_abstract = n_classkind.is_abstract
-			glob.is_universal = n_classkind.is_universal
-			if n_kwredef != null then
-				v.error(self, "Redef error: No class {name} is imported. Remove the redef keyword to define a new class.")
-			end
-
-			for c in _local_class.cshe.direct_greaters do
-				var cg = c.global
-				if glob.is_interface then
-					if cg.is_universal then
-						v.error(self, "Special error: Interface {name} try to specialise universal class {c.name}.")
-					else if not cg.is_interface then
-						v.error(self, "Special error: Interface {name} try to specialise class {c.name}.")
-					end
-				else if glob.is_universal then
-					if not cg.is_interface and not cg.is_universal then
-						v.error(self, "Special error: Universal class {name} try to specialise class {c.name}.")
-					end
-				else
-					if cg.is_universal then
-						v.error(self, "Special error: Class {name} try to specialise universal class {c.name}.")
-					end
-				end
-
-			end
-			return
-		end
-
-		# Redef
-
-		glob.check_visibility(v, self, v.module)
-		if n_kwredef == null then
-			v.error(self, "Redef error: {name} is an imported class. Add the redef keyword to refine it.")
-			return
-		end
-
-		if glob.intro.arity != _local_class.arity then
-			v.error(self, "Redef error: Formal parameter arity missmatch; got {_local_class.arity}, expected {glob.intro.arity}.")
-		end
-
-		if 
-			not glob.is_interface and n_classkind.is_interface or
-			not glob.is_abstract and n_classkind.is_abstract or
-			not glob.is_universal and n_classkind.is_universal
-		then
-			v.error(self, "Redef error: cannot change kind of class {name}.")
-		end
-	end
 
 	redef fun visibility_level
 	do
@@ -702,14 +696,14 @@ redef class AFormaldef
 		var o = c.global.intro
 		if c == o then
 			if n_type == null then
-				_formal.bound = v.module.type_any.as_nullable
+				_formal.bound = v.mmmodule.type_any.as_nullable
 			else
 				var stype = n_type.get_stype(v)
 				if stype == null then return
 				_formal.bound = stype
 			end
 		else
-			var ob = o.get_formal(_formal.position).bound.for_module(v.module)
+			var ob = o.get_formal(_formal.position).bound.for_module(v.mmmodule)
 			if n_type == null then
 				_formal.bound = ob
 			else
@@ -751,7 +745,7 @@ redef class ASuperclass
 	end
 end
 
-redef class PPropdef
+redef class APropdef
 	# Process and check properties of the property.
 	# * Distinguish inits and methods
 	# * Inherit or check visibility.
@@ -783,14 +777,14 @@ redef class PPropdef
 		if glob.is_attribute then
 			if gbc.is_interface then
 				v.error(self, "Error: Attempt to define attribute {prop} in the interface {prop.local_class}.")
-			else if gbc.is_universal then
-				v.error(self, "Error: Attempt to define attribute {prop} in the universal class {prop.local_class}.")
+			else if gbc.is_enum then
+				v.error(self, "Error: Attempt to define attribute {prop} in the enum class {prop.local_class}.")
 			end
 		else if glob.is_init then
 			if gbc.is_interface then
 				v.error(self, "Error: Attempt to define a constructor {prop} in the class {prop.local_class}.")
-			else if gbc.is_universal then
-				v.error(self, "Error: Attempt to define a constructor {prop} in the universal {prop.local_class}.")
+			else if gbc.is_enum then
+				v.error(self, "Error: Attempt to define a constructor {prop} in the enum {prop.local_class}.")
 			end
 		end
 		if prop.signature == null then
@@ -819,7 +813,6 @@ redef class PPropdef
 
 			if s == null then
 				if v.signature_builder.params.length != isig.arity then
-					#prop.node.printl("v.params.length {v.params.length} != isig.arity {isig.arity} ; {prop.full_name} vs {ip.full_name}")
 					return
 				end
 				for p in v.signature_builder.params do
@@ -854,10 +847,12 @@ redef class PPropdef
 		end
 
 		var s = prop.signature
-		#print "process {prop.local_class.module}::{prop.local_class}::{prop} from global {prop.global.local_property.local_class.module}::{prop.global.local_property.local_class}::{prop.global.local_property}"
+		#print "process {prop.local_class.mmmodule}::{prop.local_class}::{prop} from global {prop.global.local_property.local_class.mmmodule}::{prop.global.local_property.local_class}::{prop.global.local_property}"
 		for i in prop.prhe.direct_greaters do
 			var ip = i.local_class[prop.global]
-			var isig = i.signature.adaptation_to(v.local_class.get_type)
+			var isig = i.signature
+			if isig == null then break # previous signature is invalid
+			isig = isig.adaptation_to(v.local_class.get_type)
 
 			if s == null then
 				#print "{prop.full_name} inherits signature from {ip.full_name}"
@@ -893,9 +888,9 @@ redef class PPropdef
 			if s.arity != isig.arity then
 				v.error(self, "Redef error: {prop.local_class}::{prop} redefines {ip.local_class}::{ip} with {isig.arity} parameter(s).")
 			else
-				for i in [0..s.arity[ do
-					if s[i] != isig[i] then
-						v.error(self, "Redef error: Expected {isig[i]} (as in {ip.local_class}::{ip}), got {s[i]} in {prop.local_class}::{prop}.")
+				for j in [0..s.arity[ do
+					if s[j] != isig[j] then
+						v.error(self, "Redef error: Expected {isig[j]} (as in {ip.local_class}::{ip}), got {s[j]} in {prop.local_class}::{prop}.")
 					end
 				end
 			end
@@ -920,7 +915,7 @@ redef class PPropdef
 		if visibility_level != 1 and glob.visibility_level != visibility_level then
 			v.error(self, "Redef error: {prop.local_class}::{prop} redefinition cannot change visibility.")
 		end
-		glob.check_visibility(v, self, v.module, true)
+		glob.check_visibility(v, self, v.mmmodule, true)
 	end
 end
 
@@ -933,20 +928,33 @@ redef class AAttrPropdef
 	redef fun accept_property_builder(v)
 	do
 		super
-		var name = n_id.to_symbol
+		var name: Symbol
+		if n_id != null then
+			name = n_id.to_symbol
+		else
+			name = ("@" + n_id2.text).to_symbol
+		end
 		var lc = v.local_class
 		var prop = new MMSrcAttribute(name, lc, self)
 		_prop = prop
 		v.local_class.add_src_local_property(v, prop)
 
-		if n_readable != null then
-			name = n_id.text.substring_from(1).to_symbol
+		if n_readable != null or n_id == null then
+			if n_id != null then
+				name = n_id.text.substring_from(1).to_symbol
+			else
+				name = n_id2.to_symbol
+			end
 			var readmethod = new MMReadImplementationMethod(name, lc, self)
 			_readmethod = readmethod
 			v.local_class.add_src_local_property(v, readmethod)
 		end
-		if n_writable != null then
-			name = (n_id.text.substring_from(1) + "=").to_symbol
+		if n_writable != null or n_id == null then
+			if n_id != null then
+				name = (n_id.text.substring_from(1) + "=").to_symbol
+			else
+				name = (n_id2.text + "=").to_symbol
+			end
 			var writemethod = new MMWriteImplementationMethod(name, lc, self)
 			_writemethod = writemethod
 			v.local_class.add_src_local_property(v, writemethod)
@@ -961,7 +969,7 @@ redef class AAttrPropdef
 			var t0 = n_type.get_stype(v)
 			if t0 != null then t = t0 else return
 		else
-			v.error(self, "Not yet implemented: Attribute definition {_prop.local_class}::{_prop} requires an explicit type.")
+			v.error(self, "Not yet implemented: Attribute definition {prop.local_class}::{prop} requires an explicit type.")
 			return
 		end
 
@@ -969,17 +977,21 @@ redef class AAttrPropdef
 		var signature = new MMSignature(new Array[MMType], t, v.local_class.get_type)
 		prop.signature = signature
 		var visibility_level = n_visibility.level
-		process_and_check(v, prop, n_kwredef != null, visibility_level)
-		if n_readable != null then
+		process_and_check(v, prop, n_id != null and n_kwredef != null, visibility_level)
+		if n_readable != null or n_id == null then
 			var m = _readmethod.as(not null)
 			m.signature = signature
-			process_and_check(v, m, n_readable.n_kwredef != null, visibility_level)
+			process_and_check(v, m, (n_readable != null and n_readable.n_kwredef != null) or (n_id == null and n_kwredef != null), visibility_level)
 			n_type.check_visibility(v, m)
 		end
-		if n_writable != null then
+		if n_writable != null or n_id == null then
 			var m = _writemethod.as(not null)
 			m.signature = new MMSignature(new Array[MMType].with_items(t), null, v.local_class.get_type)
-			process_and_check(v, m, n_writable.n_kwredef != null, visibility_level)
+			var vl = visibility_level
+			if n_id == null then
+				if n_writable == null then vl = 3 else vl = n_writable.n_visibility.level # write accessor has a specific visibility
+			end
+			process_and_check(v, m, n_writable != null and n_writable.n_kwredef != null, vl)
 			n_type.check_visibility(v, m)
 		end
 	end
@@ -1014,7 +1026,7 @@ redef class AMethPropdef
 			# FIXME: Add the 'unary' keyword
 			if n_methid.name == (once "-".to_symbol) then
 				var ns = n_signature
-				if ns isa ASignature and ns.n_params.length == 0 then
+				if ns != null and ns.n_params.length == 0 then
 					name = once "unary -".to_symbol
 				end
 			end
@@ -1062,6 +1074,21 @@ redef class AMainMethPropdef
 	end
 end
 
+redef class AExternMethPropdef
+	redef fun accept_property_verifier(v)
+	do
+		super # Compute signature
+		var ename: String
+		if n_extern != null then
+			ename = n_extern.text
+			ename = ename.substring(1, ename.length-2)
+		else
+			ename = "{method.mmmodule.name}_{method.local_class.name}_{method.local_class.name}_{method.name}_{method.signature.arity}"
+		end
+		method.extern_name = ename
+	end
+end
+
 redef class ATypePropdef
 	redef fun prop do return _prop.as(not null)
 	var _prop: nullable MMSrcTypeProperty
@@ -1094,7 +1121,7 @@ end
 
 # Visitor used to build a full method name from multiple tokens
 private class MethidAccumulator
-special Visitor
+	super Visitor
 	readable var _name: Buffer = new Buffer
 	redef fun visit(n)
 	do
@@ -1106,7 +1133,7 @@ special Visitor
 	end
 end
 
-redef class PMethid
+redef class AMethid
 	# Method name
 	readable var _name: nullable Symbol 
 
@@ -1119,11 +1146,6 @@ redef class PMethid
 	end
 end
 
-redef class PSignature
-	# Check that visibilities of types in the signature are compatible with the visibility of the property.
-	fun check_visibility(v: AbsSyntaxVisitor, p: MMLocalProperty) is abstract
-end
-
 redef class ASignature
 	redef fun accept_property_verifier(v)
 	do
@@ -1158,7 +1180,8 @@ redef class ASignature
 		end
 	end
 
-	redef fun check_visibility(v, p)
+	# Check that visibilities of types in the signature are compatible with the visibility of the property.
+	fun check_visibility(v: AbsSyntaxVisitor, p: MMLocalProperty)
 	do
 		if p.global.visibility_level >= 3 then return
 		for n in n_params do
@@ -1168,7 +1191,7 @@ redef class ASignature
 	end
 end
 
-redef class PParam
+redef class AParam
 	redef readable var _position: Int = 0
 
 	redef fun variable: ParamVariable do return _variable.as(not null)
@@ -1181,7 +1204,7 @@ redef class PParam
 	do
 		super
 		_position = v.signature_builder.params.length
-		_variable = new ParamVariable(n_id.to_symbol, self)
+		_variable = new ParamVariable(n_id.to_symbol, n_id)
 		v.signature_builder.params.add(self)
 		v.signature_builder.untyped_params.add(self)
 		if n_type != null then
@@ -1206,11 +1229,7 @@ redef class PParam
 		end
 	end
 
-	fun is_vararg: Bool is abstract
-end
-
-redef class AParam
-	redef fun is_vararg do return n_dotdotdot != null
+	fun is_vararg: Bool do return n_dotdotdot != null
 end
 
 redef class AClosureDecl
@@ -1236,25 +1255,28 @@ redef class AClosureDecl
 		end
 
 		# Add the finalizer to the closure signature
-		var finalize_sig = new MMSignature(new Array[MMType], null, v.module.type_any) # FIXME should be no receiver
-		var finalizer_clos = new MMClosure(finalize_sig, false, true)
+		var finalize_sig = new MMSignature(new Array[MMType], null, v.mmmodule.type_any) # FIXME should be no receiver
+		var finalizer_clos = new MMClosure(once ("break".to_symbol), finalize_sig, false, true)
 		sig.closures.add(finalizer_clos)
 
-		var clos = new MMClosure(sig, n_kwbreak != null, n_expr != null)
+		var name = n_id.to_symbol
+		var clos = new MMClosure(name, sig, n_kwbreak != null, n_expr != null)
+		for c in old_signature_builder.closure_decls do
+			if c.n_id.to_symbol == name then
+				v.error(n_id, "A closure '!{name}' already defined at {c.n_id.location.relative_to(n_id.location)}.")
+				return
+			end
+		end
 		v.signature_builder = old_signature_builder
 		_position = old_signature_builder.closure_decls.length
 		old_signature_builder.closure_decls.add(self)
-		_variable = new ClosureVariable(n_id.to_symbol, self, clos)
+		_variable = new ClosureVariable(n_id.to_symbol, n_id, clos)
 	end
 end
 
-redef class PType
-	# Check that visibilities of types in the signature are compatible with the visibility of the property.
-	private fun check_visibility(v: AbsSyntaxVisitor, p: MMLocalProperty) is abstract
-end
-
 redef class AType
-	redef fun check_visibility(v, p)
+	# Check that visibilities of types in the signature are compatible with the visibility of the property.
+	private fun check_visibility(v: AbsSyntaxVisitor, p: MMLocalProperty)
 	do
 		if p.global.visibility_level >= 3 then return
 		var t = get_stype(v)
@@ -1269,7 +1291,7 @@ redef class AType
 	end
 end
 
-redef class PExpr
+redef class AExpr
 	redef fun accept_class_builder(v) do end
 	redef fun accept_property_builder(v) do end
 	redef fun accept_property_verifier(v) do end