add editor and frontmatter thing

variables/types.go

@@ -0,0 +1,13 @@
+package variables
+
+import "reflect"
+
+// IsMap checks if some variable is a map
+func IsMap(sth interface{}) bool {
+	return reflect.ValueOf(sth).Kind() == reflect.Map
+}
+
+// IsSlice checks if some variable is a slice
+func IsSlice(sth interface{}) bool {
+	return reflect.ValueOf(sth).Kind() == reflect.Slice
+}