module Bigbuffer:sig
..end
This module implements string buffers that automatically expand as necessary. It provides accumulative concatenation of strings in quasi-linear time (instead of quadratic time when strings are concatenated pairwise).
This implementation uses Bigstrings instead of strings. This removes the 16MB limit on
buffer size, and improves I/O-performance when reading/writing from/to channels.
type
t
val create : int -> t
create n
returns a fresh buffer, initially empty.
The n
parameter is the initial size of the internal string
that holds the buffer contents. That string 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
val big_contents : t -> Bigstring.t
val volatile_contents : t -> Bigstring.t
Bigbuffer.t
.include Blit.S_distinct
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 string dst
, starting at character dst_pos
.
Raise 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
.
val nth : t -> int -> char
Invalid_argument
if index out of boundsval length : t -> int
val clear : t -> unit
val reset : t -> unit
n
that was allocated by Bigbuffer.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 -> int -> int -> unit
add_substring b s ofs len
takes len
characters from offset
ofs
in string s
and appends them at the end of the buffer b
.val add_substitute : t -> (string -> string) -> string -> unit
add_substitute b f s
appends the string pattern s
at the end
of the buffer b
with substitution.
The substitution process looks for variables into
the pattern and substitutes each variable name by its value, as
obtained by applying the mapping f
to the variable name. Inside the
string pattern, a variable name immediately follows a non-escaped
$
character and is one of the following:_
characters,$
character is a $
that immediately follows a backslash
character; it then stands for a plain $
.
Raise Not_found
if the closing character of a parenthesized variable
cannot be found.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.module Format:sig
..end
module Printf:sig
..end