diff --git a/curl_default_function.e b/curl_default_function.e
index 644142fb..099fd32f 100644
--- a/curl_default_function.e
+++ b/curl_default_function.e
@@ -41,7 +41,7 @@ feature -- Command
 			create l_c_string.make_shared_from_pointer_and_count (a_data_pointer, Result)
 
 			create l_identified
-			if {l_string: CURL_STRING} l_identified.id_object (a_object_id.to_integer_32) then
+			if attached {CURL_STRING} l_identified.id_object (a_object_id.to_integer_32) as l_string then
 				l_string.append (l_c_string.string)
 			else
 				check False end
diff --git a/curl_easy_externals.e b/curl_easy_externals.e
index 0c88d61a..4ee7d90e 100644
--- a/curl_easy_externals.e
+++ b/curl_easy_externals.e
@@ -145,7 +145,7 @@ feature -- Special setting
 	curl_function: CURL_FUNCTION
 			-- cURL functions in curl_easy_setopt.
 		do
-			if {l_curl_function: like curl_function} internal_curl_function then
+			if attached {like curl_function} internal_curl_function as l_curl_function then
 				Result := l_curl_function
 			else
 				create {CURL_DEFAULT_FUNCTION} Result.make
@@ -198,7 +198,7 @@ feature -- Special setting
 
 feature {NONE} -- Implementation
 
-	internal_curl_function: ?CURL_FUNCTION
+	internal_curl_function: detachable CURL_FUNCTION
 			-- cURL functions.
 
 	api_loader: API_LOADER