diff --git a/autoload/ale/util.vim b/autoload/ale/util.vim
index 99cd856a..8d166625 100644
--- a/autoload/ale/util.vim
+++ b/autoload/ale/util.vim
@@ -336,15 +336,11 @@ function! ale#util#GetMatches(lines, patterns) abort
 endfunction
 
 function! s:LoadArgCount(function) abort
-    let l:Function = a:function
-
-    redir => l:output
-        silent! function Function
-    redir END
-
-    if !exists('l:output')
+    try
+        let l:output = execute('function a:function')
+    catch /E123/
         return 0
-    endif
+    endtry
 
     let l:match = matchstr(split(l:output, "\n")[0], '\v\([^)]+\)')[1:-2]
     let l:arg_list = filter(split(l:match, ', '), 'v:val isnot# ''...''')