diff --git a/include/xo/reader/exprstate.hpp b/include/xo/reader/exprstate.hpp
index 65dd944e..37687a56 100644
--- a/include/xo/reader/exprstate.hpp
+++ b/include/xo/reader/exprstate.hpp
@@ -23,6 +23,11 @@ namespace xo {
              **/
             defexpr,
 
+            /** handle lambda-expression
+             *  see @ref lambda_xs
+             **/
+            lambdaexpr,
+
             /** handle parenthesized expression
              *  see @ref paren_xs
              **/
diff --git a/src/reader/exprstate.cpp b/src/reader/exprstate.cpp
index 859d0be8..a734f3b9 100644
--- a/src/reader/exprstate.cpp
+++ b/src/reader/exprstate.cpp
@@ -27,6 +27,8 @@ namespace xo {
                 return "expect_toplevel_expression_sequence";
             case exprstatetype::defexpr:
                 return "defexpr";
+            case exprstatetype::lambdaexpr:
+                return "lambdaexpr";
             case exprstatetype::parenexpr:
                 return "parenexpr";
             case exprstatetype::expect_rhs_expression: