added Buffer.sub & Buffer.nth

git-svn-id: http://caml.inria.fr/svn/ocaml/trunk@6203 f963ae5c-01c2-4b8c-9fe0-0dff7051ff02

1 files changed, 10 insertions, 0 deletions

diff --git a/stdlib/buffer.mli b/stdlib/buffer.mli
index 73e02e299b..0448df7a38 100644
--- a/stdlib/buffer.mli
+++ b/stdlib/buffer.mli
@@ -40,6 +40,16 @@ val contents : t -> string
 (** Return a copy of the current contents of the buffer.
    The buffer itself is unchanged. *)
 
+val sub : t -> int -> int -> string
+(** [Buffer.sub b off len] returns (a copy of) the substring of the
+current contents of the buffer [b] starting at offset [off] of length
+[len] bytes. May raise {!Invalid_arg} if out of bounds request. The
+buffer itself is unaffected. *)
+
+val nth : t -> int -> char
+(** get the n-th character of the buffer. Raise {!Invalid_arg} if
+index out of bounds *)
+
 val length : t -> int
 (** Return the number of characters currently contained in the buffer. *)