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Module Buffermodule 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
concatenated pairwise). type t
The abstract type of buffers.
val create : 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.
If n is not between 1 and Sys.max_string_length , it will
be clipped to that interval.val contents :
Return a copy of the current contents of the buffer.
The buffer itself is unchanged.
val length :
Return the number of characters currently contained in the buffer.
val clear :
Empty the buffer.
val reset :
Empty the buffer and deallocate the internal string holding the
buffer contents, replacing it with the initial internal string
of length
n that was allocated by Buffer.create n .
For long-lived buffers that may have grown a lot, reset allows
faster reclaimation of the space used by the buffer.val add_char : add_char b c appends the character c at the end of the buffer b .val add_string : add_string b s appends the string s at the end of the buffer b .val add_substring : 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_buffer : add_buffer b1 b2 appends the current contents of buffer b2
at the end of buffer b1 . b2 is not modified.val add_channel : add_channel b ic n reads exactly n character from the
input channel ic and stores them at the end of buffer b .
Raise End_of_file if the channel contains fewer than n
characters.val output_buffer : output_buffer oc b writes the current contents of buffer b
on the output channel oc . |