diff --git a/pervasives.eff b/pervasives.eff
index 140de554..14228e79 100644
--- a/pervasives.eff
+++ b/pervasives.eff
@@ -75,6 +75,10 @@ external ( ^ ) : string -> string -> string = "^"
 
 external string_length : string -> int = "string_length"
 
+external trim : string -> string = "trim"
+
+external split_on_char : char -> string -> string list = "split_on_char"
+
 external to_string : 'a -> string  = "to_string"
 
 type 'a option = None | Some of 'a
diff --git a/src/runtime/external.ml b/src/runtime/external.ml
index 6a18d5c4..c1fd3545 100644
--- a/src/runtime/external.ml
+++ b/src/runtime/external.ml
@@ -1,5 +1,7 @@
 module V = Value
 
+let from_char c = V.Const (Const.of_char c)
+
 let from_bool b = V.Const (Const.of_boolean b)
 
 let from_int n = V.Const (Const.of_integer n)
@@ -10,6 +12,8 @@ let from_float f = V.Const (Const.of_float f)
 
 let from_fun f = V.Closure f
 
+let value_list b = V.Value (Tuple b)
+
 let value_bool b = V.Value (from_bool b)
 
 let value_int n = V.Value (from_int n)
@@ -158,10 +162,19 @@ let arithmetic_operations =
   ; ("/.", float_float_to_float ( /. )) ]
 
 
+let string_string_to_list f =
+	let ff v1 v2 =  value_list (List.map from_str (f (V.to_char v1) (V.to_str v2))) in
+	binary_closure ff
+    
+    
 let string_operations =
   [ ("^", binary_closure (fun v1 v2 -> value_str (V.to_str v1 ^ V.to_str v2)))
-  ; ( "string_length"
-    , from_fun (fun v -> value_int (String.length (V.to_str v))) ) ]
+  ; ( "string_length", from_fun (fun v -> value_int (String.length (V.to_str v))) ) 
+  ; ( "trim", from_fun (fun v -> value_str (String.trim (V.to_str v))) ) 
+  ; ( "split_on_char", string_string_to_list String.split_on_char)
+  ]
+
+
 
 
 let conversion_functions =
diff --git a/src/runtime/value.ml b/src/runtime/value.ml
index b1ac5b36..40747f57 100644
--- a/src/runtime/value.ml
+++ b/src/runtime/value.ml
@@ -31,6 +31,10 @@ let to_out_channel = function
  | _ -> Error.runtime "A out_channel value expected."
 
 
+let to_char = function
+  | Const Const.Char b -> b
+  | _ -> Error.runtime "A char value expected."
+
 let to_bool = function
   | Const Const.Boolean b -> b
   | _ -> Error.runtime "A boolean value expected."
diff --git a/src/runtime/value.mli b/src/runtime/value.mli
index c04e944d..85e59116 100644
--- a/src/runtime/value.mli
+++ b/src/runtime/value.mli
@@ -20,6 +20,8 @@ val second : value -> value
 val to_out_channel : value -> out_channel
 val to_in_channel : value -> in_channel
 
+val to_char : value -> char
+
 val to_bool : value -> bool
 
 val to_int : value -> int
diff --git a/src/typing/infer.ml b/src/typing/infer.ml
index 9e075f7f..2c4b56d0 100644
--- a/src/typing/infer.ml
+++ b/src/typing/infer.ml
@@ -45,6 +45,7 @@ let ty_of_const = function
   | Const.Float _ -> Type.float_ty
   | Const.Out_channel _ -> Type.out_channel_ty
   | Const.In_channel _ -> Type.in_channel_ty
+  | Const.Char _ -> Type.char_ty
 
 
 (* [infer_pattern cstr pp] infers the type of pattern [pp]. It returns the list of
diff --git a/src/typing/tctx.ml b/src/typing/tctx.ml
index d8ab8a74..b12e036c 100644
--- a/src/typing/tctx.ml
+++ b/src/typing/tctx.ml
@@ -12,6 +12,7 @@ type tyctx = (OldUtils.tyname, Type.ty_param list * tydef) OldUtils.assoc
 let initial : tyctx =
   [ ("in_channel", ([], Inline T.in_channel_ty))
   ; ("out_channel", ([], Inline T.out_channel_ty))
+  ; ("char", ([], Inline T.char_ty))
   ; ("bool", ([], Inline T.bool_ty))
   ; ("unit", ([], Inline T.unit_ty))
   ; ("int", ([], Inline T.int_ty))
diff --git a/src/typing/type.ml b/src/typing/type.ml
index 9a127d8a..42625c11 100644
--- a/src/typing/type.ml
+++ b/src/typing/type.ml
@@ -29,6 +29,8 @@ let out_channel_ty = Basic "out_channel"
   
 let universal_ty = Basic "_"
 
+let char_ty = Basic "char"
+
 let int_ty = Basic "int"
 
 let string_ty = Basic "string"
diff --git a/src/utils/const.ml b/src/utils/const.ml
index 841f1e1f..71b2c9db 100644
--- a/src/utils/const.ml
+++ b/src/utils/const.ml
@@ -1,4 +1,5 @@
 type t =
+  | Char of char
   | Integer of int
   | String of string
   | Boolean of bool
@@ -10,6 +11,8 @@ type t =
 let of_in_channel n = In_channel n
 let of_out_channel n = Out_channel n
 
+let of_char c = Char c
+
 let of_integer n = Integer n
 
 let of_string s = String s
@@ -24,6 +27,7 @@ let of_false = of_boolean false
 
 let print c ppf =
   match c with
+  | Char k -> Format.fprintf ppf "%c" k
   | Integer k -> Format.fprintf ppf "%d" k
   | String s -> Format.fprintf ppf "%S" s
   | Boolean b -> Format.fprintf ppf "%B" b
@@ -44,6 +48,7 @@ let compare c1 c2 =
   | String s1, String s2 -> cmp s1 s2
   | Boolean b1, Boolean b2 -> cmp b1 b2
   | Float x1, Float x2 -> cmp x1 x2
+  | Char x1, Char x2 -> cmp x1 x2
   | _ -> Error.runtime "Incomparable constants %t and %t" (print c1) (print c2)
 
 
diff --git a/src/utils/const.mli b/src/utils/const.mli
index 22d2d31a..d789cc3d 100644
--- a/src/utils/const.mli
+++ b/src/utils/const.mli
@@ -1,4 +1,5 @@
 type t = private
+  | Char of char
   | Integer of int
   | String of string
   | Boolean of bool
@@ -9,6 +10,8 @@ type t = private
 val of_in_channel : in_channel -> t
 val of_out_channel : out_channel -> t
 
+val of_char : char -> t
+
 val of_integer : int -> t
 
 val of_string : string -> t