|| Module Buffer: extensible string buffers
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
The abstract type of buffers.
val create : int -> t
create n returns a fresh buffer, initially empty.
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.
n is not between 1 and
Sys.max_string_length, it will
be clipped to that interval.
val contents : t -> string
Return a copy of the current contents of the buffer.
The buffer itself is unchanged.
val length : t -> int
Return the number of characters currently contained in the buffer.
val clear : t -> unit
Empty the buffer.
val reset : t -> unit
Empty the buffer and deallocate the internal string holding the
buffer contents, replacing it with the initial internal string
n that was allocated by
For long-lived buffers that may have grown a lot,
faster reclaimation 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
val add_string : t -> string -> unit
add_string b s appends the string
s at the end of
val add_substring : t -> string -> pos:int -> len: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
val add_buffer : t -> src:t -> unit
add_buffer b1 b2 appends the current contents of buffer
at the end of buffer
b2 is not modified.
val add_channel : t -> in_channel -> len:int -> unit
add_channel b ic n reads exactly
n character from the
ic and stores them at the end of buffer
End_of_file if the channel contains fewer than
val output_buffer : out_channel -> t -> unit
output_buffer oc b writes the current contents of buffer
on the output channel