Use Re

lib/switch_name.ml

@@ -8,22 +8,17 @@ let to_string s = s
 
 let invalid_chars = [ '/'; ':'; '#' ]
 
-let count_leading_dashes s =
-  let exception Done in
-  let r = ref 0 in
-  (try String.iter (function '-' -> incr r | _ -> raise Done) s
-   with Done -> ());
-  !r
-
-let strip_leading_dashes s =
-  let n = count_leading_dashes s in
-  let s_len = String.length s in
-  String.sub s n (s_len - n)
-
-let escape_string s =
-  s
-  |> String.map (fun c -> if List.mem c invalid_chars then '-' else c)
-  |> strip_leading_dashes
+let strip_leading_dashes =
+  let open Re in
+  let re = compile (seq [ bos; rep1 (char '-') ]) in
+  replace_string re ~by:""
+
+let remove_invalid_chars =
+  let open Re in
+  let re = compile (alt (List.map char invalid_chars)) in
+  replace_string re ~by:"-"
+
+let escape_string s = s |> remove_invalid_chars |> strip_leading_dashes
 
 let parse s =
   if List.exists (fun c -> String.contains s c) invalid_chars then