From: Jean Privat <jean@pryen.org>
Date: Fri, 26 Feb 2016 21:00:58 +0000 (-0500)
Subject: modelize: new attribute annotation `is optional`
X-Git-Url: http://nitlanguage.org

modelize: new attribute annotation `is optional`

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

diff --git a/src/frontend/check_annotation.nit b/src/frontend/check_annotation.nit
index d640ac2..5adcabd 100644
--- a/src/frontend/check_annotation.nit
+++ b/src/frontend/check_annotation.nit
@@ -84,6 +84,7 @@ lazy
 noinit
 readonly
 writable
+optional
 autoinit
 noautoinit
 lateinit
diff --git a/src/modelize/modelize_property.nit b/src/modelize/modelize_property.nit
index e61713d..6588268 100644
--- a/src/modelize/modelize_property.nit
+++ b/src/modelize/modelize_property.nit
@@ -203,7 +203,7 @@ redef class ModelBuilder
 					mreadpropdef.mproperty.is_autoinit = true
 					continue
 				end
-				if npropdef.has_value then continue
+				if npropdef.has_value and not npropdef.is_optional then continue
 				var msetter = npropdef.mwritepropdef
 				if msetter == null then
 					# No setter, it is a readonly attribute, so just add it
@@ -212,6 +212,7 @@ redef class ModelBuilder
 					if ret_type == null then return
 					var mparameter = new MParameter(paramname, ret_type, false)
 					mparameters.add(mparameter)
+
 					initializers.add(npropdef.mpropdef.mproperty)
 					npropdef.mpropdef.mproperty.is_autoinit = true
 				else
@@ -1155,6 +1156,9 @@ redef class AAttrPropdef
 	# Is the node tagged lazy?
 	var is_lazy = false
 
+	# Is the node tagged optional?
+	var is_optional = false
+
 	# Has the node a default value?
 	# Could be through `n_expr` or `n_block`
 	var has_value = false
@@ -1251,6 +1255,14 @@ redef class AAttrPropdef
 			self.mlazypropdef = mlazypropdef
 		end
 
+		var atoptional = self.get_single_annotation("optional", modelbuilder)
+		if atoptional != null then
+			if not has_value then
+				modelbuilder.error(atoptional, "Error: `optional` attributes need a default value.")
+			end
+			is_optional = true
+		end
+
 		var atreadonly = self.get_single_annotation("readonly", modelbuilder)
 		if atreadonly != null then
 			if not has_value then
@@ -1422,9 +1434,13 @@ redef class AAttrPropdef
 
 		var mwritepropdef = self.mwritepropdef
 		if mwritepropdef != null then
+			var mwritetype = mtype
+			if is_optional then
+				mwritetype = mwritetype.as_nullable
+			end
 			var name: String
 			name = n_id2.text
-			var mparameter = new MParameter(name, mtype, false)
+			var mparameter = new MParameter(name, mwritetype, false)
 			var msignature = new MSignature([mparameter], null)
 			mwritepropdef.msignature = msignature
 		end