From: Jean Privat <jean@pryen.org>
Date: Thu, 11 Jun 2009 15:45:43 +0000 (-0400)
Subject: metamodel: fast-fail in getters
X-Git-Tag: v0.3~277
X-Git-Url: http://nitlanguage.org

metamodel: fast-fail in getters

Instead of testing and returning null among getters, just do stuff and
abort if called methods abort.

syntax modules are adapted to use preventive methods (has_*).

Signed-off-by: Jean Privat <jean@pryen.org>
---

diff --git a/src/metamodel/abstractmetamodel.nit b/src/metamodel/abstractmetamodel.nit
index 4e3dbff..260ea30 100644
--- a/src/metamodel/abstractmetamodel.nit
+++ b/src/metamodel/abstractmetamodel.nit
@@ -217,11 +217,7 @@ class MMModule
 	do
 		assert _local_class_by_global != null
 		assert c != null
-		if _local_class_by_global.has_key(c) then
-			return _local_class_by_global[c]
-		else
-			return null
-		end
+		return _local_class_by_global[c]
 	end
 
 	# Register a local class to the module
@@ -247,11 +243,7 @@ class MMModule
 	# Return null if not class match this name
 	meth global_class_named(n: Symbol): MMGlobalClass
 	do
-		if _global_class_by_name.has_key(n) then
-			return _global_class_by_name[n]
-		else
-			return null
-		end
+		return _global_class_by_name[n]
 	end
 
 	redef meth to_s do return name.to_s
@@ -419,16 +411,15 @@ class MMLocalClass
 	# TODO: Will disapear when qualified names will be available
 	meth has_global_property_by_name(n: Symbol): Bool
 	do
-		return _properties_by_name.has_key(n)
+		return _properties_by_name.has_key(n) and _properties_by_name[n].length == 1
 	end
 
 	# Get a global property by its name
 	# TODO: Will disapear when qualified names will be available
 	meth get_property_by_name(n: Symbol): MMGlobalProperty
 	do
-		if not has_global_property_by_name(n) then return null
+		if not has_global_property_by_name(n) then abort
 		var props = _properties_by_name[n]
-		if props.length > 1 then return null
 		return props.first
 	end
 
@@ -444,11 +435,7 @@ class MMLocalClass
 	meth method(na: Symbol): MMGlobalProperty
 	do
 		assert _properties_by_name != null
-		if _properties_by_name.has_key(na) then
-			return _properties_by_name[na].first
-		end
-
-		return null
+		return _properties_by_name[na].first
 	end
 
 	# Select a method from its name
@@ -457,7 +444,6 @@ class MMLocalClass
 	do
 		assert name != null
 		var gp = method(name)
-		if gp == null then return null
 		var res = self[gp]
 		assert res isa MMMethod
 		return res
@@ -469,7 +455,6 @@ class MMLocalClass
 	do
 		assert name != null
 		var gp = attribute(name)
-		if gp == null then return null
 		var res = self[gp]
 		assert res isa MMAttribute
 		return res
@@ -481,9 +466,7 @@ class MMLocalClass
 	do
 		var classes = new Array[MMLocalClass]
 		for c in cshe.greaters do
-			var g = c.method(n)
-			if g == null then continue
-			classes.add(c)
+			if c.has_global_property_by_name(n) then classes.add(c)
 		end
 		classes = cshe.order.select_smallests(classes)
 		var res = new Array[MMLocalProperty]
@@ -522,12 +505,7 @@ class MMLocalClass
 	# Get a local proprty by its global property
 	meth [](glob: MMGlobalProperty): MMLocalProperty
 	do
-		assert _local_property_by_global != null
-		assert glob != null
-		if _local_property_by_global.has_key(glob) then
-			return _local_property_by_global[glob]
-		end
-		return null
+		return _local_property_by_global[glob]
 	end
 
 	# The current MMContext
diff --git a/src/syntax/mmbuilder.nit b/src/syntax/mmbuilder.nit
index b0ad5ff..db15e8b 100644
--- a/src/syntax/mmbuilder.nit
+++ b/src/syntax/mmbuilder.nit
@@ -173,8 +173,9 @@ redef class MMSrcLocalClass
 				if not gp.is_init then continue
 				super_constructors.add(gp)
 			end
-			var gp = sc.get_property_by_name(once ("init".to_symbol))
-			if gp != null then
+			var initname = once ("init".to_symbol)
+			if sc.has_global_property_by_name(initname) then
+				var gp = sc.get_property_by_name(initname)
 				super_inits.add(self[gp])
 			end
 		end
diff --git a/src/syntax/typing.nit b/src/syntax/typing.nit
index b44f62a..d8ca9de 100644
--- a/src/syntax/typing.nit
+++ b/src/syntax/typing.nit
@@ -553,11 +553,12 @@ redef class AReassignFormExpr
 			return
 		end
 		var name = n_assign_op.method_name
-		var prop = type_lvalue.local_class.select_method(name)
-		if prop == null then
+		var lc = type_lvalue.local_class
+		if not lc.has_global_property_by_name(name) then
 			v.error(self, "Error: Method '{name}' doesn't exists in {type_lvalue}.")
 			return
 		end
+		var prop = lc.select_method(name)
 		prop.global.check_visibility(v, self, v.module, false)
 		var psig = prop.signature_for(type_lvalue)
 		_assign_method = prop
@@ -876,11 +877,13 @@ redef class AAttrFormExpr
 		if not v.check_expr(n_expr) then return
 		var type_recv = n_expr.stype
 		var name = n_id.to_symbol
-		var prop = type_recv.local_class.select_attribute(name)
-		if prop == null then
+		var lc = type_recv.local_class
+		if not lc.has_global_property_by_name(name) then
 			v.error(self, "Error: Attribute {name} doesn't exists in {type_recv}.")
 			return
-		else if v.module.visibility_for(prop.global.local_class.module) < 3 then
+		end
+		var prop = lc.select_attribute(name)
+		if v.module.visibility_for(prop.global.local_class.module) < 3 then
 			v.error(self, "Error: Attribute {name} from {prop.global.local_class.module} is invisible in {v.module}")
 		end
 		_prop = prop
@@ -947,7 +950,9 @@ special PExpr
 	private meth get_property(v: TypingVisitor, type_recv: MMType, is_implicit_self: Bool, name: Symbol): MMMethod
 	do
 		if type_recv == null then return null
-		var prop = type_recv.local_class.select_method(name)
+		var lc = type_recv.local_class
+		var prop: MMMethod = null
+		if lc.has_global_property_by_name(name) then prop = lc.select_method(name)
 		if prop == null and v.local_property.global.is_init then
 			var props = type_recv.local_class.super_methods_named(name)
 			if props.length > 1 then