diff --git a/traverse.go b/traverse.go
index b53145b40..01000c540 100644
--- a/traverse.go
+++ b/traverse.go
@@ -162,8 +162,7 @@ loop:
 	case !c.DisableFlagParsing && strings.HasPrefix(context.Value, "-") && (fs.IsInterspersed() || len(inPositionals) == 0):
 		if f := fs.LookupArg(context.Value); f != nil && f.IsOptarg() && strings.Contains(context.Value, string(f.OptargDelimiter())) {
 			LOG.Printf("completing optional flag argument for arg %#v\n", context.Value)
-			prefix, optarg := f.Split(context.Value)
-			context.Value = optarg
+			prefix, _ := f.Split(context.Value)
 
 			switch f.Value.Type() {
 			case "bool":