diff --git a/lib/pure/selectors.nim b/lib/pure/selectors.nim
index e89cc74472..933b5491a8 100644
--- a/lib/pure/selectors.nim
+++ b/lib/pure/selectors.nim
@@ -47,6 +47,9 @@ when defined(nimdoc):
     Selector*[T] = ref object
       ## An object which holds descriptors to be checked for read/write status
 
+    IOSelectorsException* = object of CatchableError
+      ## Exception that is raised if an IOSelectors error occurs.
+
     Event* {.pure.} = enum
       ## An enum which hold event types
       Read,        ## Descriptor is available for read