diff -r f7f9a2553128 -r 9603e64324bc src/Configuration.h
--- a/src/Configuration.h	Sun Feb 03 19:52:37 2019 +0100
+++ b/src/Configuration.h	Sun Feb 03 21:53:10 2019 +0100
@@ -54,7 +54,8 @@
 	 */
 	bool drop = false;
 	/**
-	 * 
+	 * Variable definitions for this relation.
+	 * Can be used as a safe way for passing parameters from the outside environment.
 	 */
 	std::vector<DefinitionRecipe> definitions;
 	/**
@@ -67,6 +68,11 @@
 public:
 	vector<RelationConfiguration> relationConfigurations;
 
+	// TODO: --define – global definitions (for all relations)?
+	// TODO: --relation … --drop – will execute --for-each, but no output will be generated for this relation
+	// TODO: --relation … --output-attribute 'name' 'type' – output relation will have different attributes than the input relation
+	// TODO: --create t2 3 a integer b boolean '…guile…' – allow creating new relations? Or allow calling startRelation() and attribute() from Guile?
+
 	virtual ~Configuration() {
 	}
 };