1 files changed, 3 insertions, 1 deletions
diff --git a/type.lua b/type.lua
index cf24d0c..6dbf313 100644
--- a/type.lua
+++ b/type.lua

@@ -266,7 +266,9 @@ end
 -- type assertion
 function m.assert_type (x, t)
-        if not m.isp(x, t) then
+        local pred = function (a) return m.isp(a, t) end
+        if t == "list" then pred = m.listp end
+        if not pred(x) then
                error("wrong type", m.lamtype(x), t)
        end
 end