diff --git a/language/functions.xml b/language/functions.xml
index a111885a0c..35bf832405 100644
--- a/language/functions.xml
+++ b/language/functions.xml
@@ -169,7 +169,8 @@ function recursion($a)
Information may be passed to functions via the argument list,
- which is a comma-delimited list of expressions.
+ which is a comma-delimited list of expressions. The arguments are
+ evaluated from left to right.
PHP supports passing arguments by value (the default),