module Buffer:sig..end
Extensible buffers.
This module implements 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
The abstract type of buffers.
val create : int -> tcreate n returns a fresh buffer, initially empty.
The n parameter is the initial size of the internal byte sequence
that holds the buffer contents. That byte sequence 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 : t -> stringReturn a copy of the current contents of the buffer. The buffer itself is unchanged.
val to_bytes : t -> bytesReturn a copy of the current contents of the buffer. The buffer itself is unchanged.
val sub : t -> int -> int -> stringBuffer.sub b off len returns a copy of len bytes from the
current contents of the buffer b, starting at offset off.
Invalid_argument if srcoff and len do not designate a valid
range of b.val blit : t -> int -> bytes -> int -> int -> unitBuffer.blit src srcoff dst dstoff len copies len characters from
the current contents of the buffer src, starting at offset srcoff
to dst, starting at character dstoff.
Invalid_argument if srcoff and len do not designate a valid
range of src, or if dstoff and len do not designate a valid
range of dst.val nth : t -> int -> charGet the n-th character of the buffer.
Invalid_argument if
index out of boundsval length : t -> intReturn the number of characters currently contained in the buffer.
val clear : t -> unitEmpty the buffer.
val reset : t -> unitEmpty the buffer and deallocate the internal byte sequence holding the
buffer contents, replacing it with the initial internal byte sequence
of length n that was allocated by Buffer.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 -> unitadd_char b c appends the character c at the end of buffer b.
val add_utf_8_uchar : t -> Uchar.t -> unitadd_utf_8_uchar b u appends the
UTF-8 encoding of u at the end of buffer b.
val add_utf_16le_uchar : t -> Uchar.t -> unitadd_utf_16le_uchar b u appends the
UTF-16LE encoding of u
at the end of buffer b.
val add_utf_16be_uchar : t -> Uchar.t -> unitadd_utf_16be_uchar b u appends the
UTF-16BE encoding of u
at the end of buffer b.
val add_string : t -> string -> unitadd_string b s appends the string s at the end of buffer b.
val add_bytes : t -> bytes -> unitadd_bytes b s appends the byte sequence s at the end of buffer b.
val add_substring : t -> string -> int -> int -> unitadd_substring b s ofs len takes len characters from offset
ofs in string s and appends them at the end of buffer b.
val add_subbytes : t -> bytes -> int -> int -> unitadd_subbytes b s ofs len takes len characters from offset
ofs in byte sequence s and appends them at the end of buffer b.
val add_substitute : t -> (string -> string) -> string -> unitadd_substitute b f s appends the string pattern s at the end
of 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 $.Not_found if the closing character of a parenthesized variable
cannot be found.val add_buffer : t -> t -> unitadd_buffer b1 b2 appends the current contents of buffer b2
at the end of buffer b1. b2 is not modified.
val add_channel : t -> in_channel -> int -> unitadd_channel b ic n reads at most n characters from the
input channel ic and stores them at the end of buffer b.
End_of_file if the channel contains fewer than n
characters. In this case, the characters are still added to
the buffer, so as to avoid loss of data.val output_buffer : out_channel -> t -> unitoutput_buffer oc b writes the current contents of buffer b
on the output channel oc.
val truncate : t -> int -> unittruncate b len truncates the length of b to len
Note: the internal byte sequence is not shortened.
Invalid_argument if len < 0 or len > length b.val to_seq : t -> char Seq.tIterate on the buffer, in increasing order. Modification of the buffer during iteration is undefined behavior.
val to_seqi : t -> (int * char) Seq.tIterate on the buffer, in increasing order, yielding indices along chars. Modification of the buffer during iteration is undefined behavior.
val add_seq : t -> char Seq.t -> unitAdd chars to the buffer
val of_seq : char Seq.t -> tCreate a buffer from the generator
The functions in this section append binary encodings of integers to buffers.
Little-endian (resp. big-endian) encoding means that least
(resp. most) significant bytes are stored first. Big-endian is
also known as network byte order. Native-endian encoding is
either little-endian or big-endian depending on Sys.big_endian.
32-bit and 64-bit integers are represented by the int32 and
int64 types, which can be interpreted either as signed or
unsigned numbers.
8-bit and 16-bit integers are represented by the int type,
which has more bits than the binary encoding. Functions that
encode these values truncate their inputs to their least
significant bytes.
val add_uint8 : t -> int -> unitadd_uint8 b i appends a binary unsigned 8-bit integer i to
b.
val add_int8 : t -> int -> unitadd_int8 b i appends a binary signed 8-bit integer i to
b.
val add_uint16_ne : t -> int -> unitadd_uint16_ne b i appends a binary native-endian unsigned 16-bit
integer i to b.
val add_uint16_be : t -> int -> unitadd_uint16_be b i appends a binary big-endian unsigned 16-bit
integer i to b.
val add_uint16_le : t -> int -> unitadd_uint16_le b i appends a binary little-endian unsigned 16-bit
integer i to b.
val add_int16_ne : t -> int -> unitadd_int16_ne b i appends a binary native-endian signed 16-bit
integer i to b.
val add_int16_be : t -> int -> unitadd_int16_be b i appends a binary big-endian signed 16-bit
integer i to b.
val add_int16_le : t -> int -> unitadd_int16_le b i appends a binary little-endian signed 16-bit
integer i to b.
val add_int32_ne : t -> int32 -> unitadd_int32_ne b i appends a binary native-endian 32-bit integer
i to b.
val add_int32_be : t -> int32 -> unitadd_int32_be b i appends a binary big-endian 32-bit integer
i to b.
val add_int32_le : t -> int32 -> unitadd_int32_le b i appends a binary little-endian 32-bit integer
i to b.
val add_int64_ne : t -> int64 -> unitadd_int64_ne b i appends a binary native-endian 64-bit integer
i to b.
val add_int64_be : t -> int64 -> unitadd_int64_be b i appends a binary big-endian 64-bit integer
i to b.
val add_int64_le : t -> int64 -> unitadd_int64_ne b i appends a binary little-endian 64-bit integer
i to b.