diff --git a/autoload/vimwiki/base.vim b/autoload/vimwiki/base.vim
index ecc322b..6f81453 100644
--- a/autoload/vimwiki/base.vim
+++ b/autoload/vimwiki/base.vim
@@ -1325,12 +1325,14 @@ function! vimwiki#base#goto_index(wnum, ...) "{{{
     let idx = 0
   endif
 
-  if a:1 == 1
-    let cmd = 'tabedit'
-  elseif a:1 == 2
-    let cmd = 'split'
-  elseif a:1 == 3
-    let cmd = 'vsplit'
+  if a:0
+    if a:1 == 1
+      let cmd = 'tabedit'
+    elseif a:1 == 2
+      let cmd = 'split'
+    elseif a:1 == 3
+      let cmd = 'vsplit'
+    endif
   else
     let cmd = 'edit'
   endif