Module Base.Buffer

Extensible character buffers.

This module implements character buffers that automatically expand as necessary. It provides cumulative concatenation of strings in quasi-linear time (instead of quadratic time when strings are concatenated pairwise).

module type S = sig ... end

Buffers using strings as underlying storage medium:

include S with type t = Buffer.t
type t = Buffer.t

The abstract type of buffers.

val sexp_of_t : t -> Sexplib0.Sexp.t
val create : int -> t

create n returns a fresh buffer, initially empty. The n parameter is the initial size of the internal storage medium that holds the buffer contents. That storage is automatically reallocated when more than n characters are stored in the buffer, but shrinks back to n characters when reset is called.

For best performance, n should be of the same order of magnitude as the number of characters that are expected to be stored in the buffer (for instance, 80 for a buffer that holds one output line). Nothing bad will happen if the buffer grows beyond that limit, however. In doubt, take n = 16 for instance.

val contents : t -> string

Return a copy of the current contents of the buffer. The buffer itself is unchanged.

val contents_bytes : t -> bytes

blit ~src ~src_pos ~dst ~dst_pos ~len copies len characters from the current contents of the buffer src, starting at offset src_pos to bytes dst, starting at character dst_pos.

Raises Invalid_argument if src_pos and len do not designate a valid substring of src, or if dst_pos and len do not designate a valid substring of dst.

include Blit.S_distinct with type src := t with type dst := bytes
val blit : src:t -> src_pos:int -> dst:bytes -> dst_pos:int -> len:int -> unit
val blito : src:t -> ?src_pos:int -> ?src_len:int -> dst:bytes -> ?dst_pos:int -> unit -> unit
val unsafe_blit : src:t -> src_pos:int -> dst:bytes -> dst_pos:int -> len:int -> unit
val sub : t -> pos:int -> len:int -> bytes
val subo : ?pos:int -> ?len:int -> t -> bytes
module To_string : Blit.S_to_string with type t := t
val nth : t -> int -> char

Gets the (zero-based) n-th character of the buffer. Raises Invalid_argument if index out of bounds.

val length : t -> int

Returns the number of characters currently contained in the buffer.

val clear : t -> unit

Empties the buffer.

val reset : t -> unit

Empties the buffer and deallocates the internal storage holding the buffer contents, replacing it with the initial internal storage of length n that was allocated by create n. For long-lived buffers that may have grown a lot, reset allows faster reclamation of the space used by the buffer.

val add_char : t -> char -> unit

add_char b c appends the character c at the end of the buffer b.

val add_string : t -> string -> unit

add_string b s appends the string s at the end of the buffer b.

val add_substring : t -> string -> pos:int -> len:int -> unit

add_substring b s pos len takes len characters from offset pos in string s and appends them at the end of the buffer b.

val add_bytes : t -> bytes -> unit

add_bytes b s appends the bytes s at the end of the buffer b.

val add_subbytes : t -> bytes -> pos:int -> len:int -> unit

add_subbytes b s pos len takes len characters from offset pos in bytes s and appends them at the end of the buffer b.

val add_buffer : t -> t -> unit

add_buffer b1 b2 appends the current contents of buffer b2 at the end of buffer b1. b2 is not modified.