Module Stdlib.Buffer
Contents
Instructions: Use this module in your project
In the IDE (CLion, Visual Studio Code, Xcode, etc.) you use for your DkSDK project:
Add the following to your project's
dependencies/CMakeLists.txt
:DkSDKProject_DeclareAvailable(ocaml CONSTRAINT "= 4.14.0" FINDLIBS str unix runtime_events threads dynlink) DkSDKProject_MakeAvailable(ocaml)
Add the
Findlib::ocaml
library to any desired targets insrc/*/CMakeLists.txt
:target_link_libraries(YourPackage_YourLibraryName # ... existing libraries, if any ... Findlib::ocaml)
Click your IDE's
Build
button
Not using DkSDK?
FIRST, do one or all of the following:
Run:
opam install ocaml.4.14.0
Edit your
dune-project
and add:(package (name YourExistingPackage) (depends ; ... existing dependenices ... (ocaml (>= 4.14.0))))
Then run:
dune build *.opam # if this fails, run: dune build
Edit your
<package>.opam
file and add:depends: [ # ... existing dependencies ... "ocaml" {>= "4.14.0"} ]
Then run:
opam install . --deps-only
FINALLY, add the library to any desired
(library)
and/or (executable)
targets in your **/dune
files:
(library
(name YourLibrary)
; ... existing library options ...
(libraries
; ... existing libraries ...
))
(executable
(name YourExecutable)
; ... existing executable options ...
(libraries
; ... existing libraries ...
))
type
t
The abstract type of buffers.
val
create : ``int
->
t
create 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
->
string
Return a copy of the current contents of the buffer. The buffer itself is unchanged.
val
to_bytes :
t
->
bytes
Return a copy of the current contents of the buffer. The buffer itself is unchanged.
- since 4.02
val
sub :
t
->
``int
->
``int
->
string
Buffer.sub b off len
returns a copy of len
bytes from the current
contents of the buffer b
, starting at offset off
.
-
raises Invalid_argument
if
off
andlen
do not designate a valid range ofb
.
val
blit :
t
->
``int
->
``bytes
->
``int
->
``int
->
unit
Buffer.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
.
-
raises Invalid_argument
if
srcoff
andlen
do not designate a valid range ofsrc
, or ifdstoff
andlen
do not designate a valid range ofdst
. -
since 3.11.2
val
nth :
t
->
``int
->
char
Get the n-th character of the buffer.
-
raises Invalid_argument
if index out of bounds
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 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
output_buffer :
out_channel
->
t
->
unit
output_buffer oc b
writes the current contents of buffer b
on the
output channel oc
.
val
truncate :
t
->
``int
->
unit
truncate b len
truncates the length of b
to len
Note: the internal
byte sequence is not shortened.
-
raises Invalid_argument
if
len < 0
orlen > length b
. -
since 4.05.0
Appending
Note: all add_*
operations can raise Failure
if the internal byte
sequence of the buffer would need to grow beyond
Sys.max_string_length
.
val
add_char :
t
->
``char
->
unit
add_char b c
appends the character c
at the end of buffer b
.
add_utf_8_uchar b u
appends the
UTF-8 encoding of u
at the end
of buffer b
.
- since 4.06.0
add_utf_16le_uchar b u
appends the
UTF-16LE encoding of u
at the
end of buffer b
.
- since 4.06.0
add_utf_16be_uchar b u
appends the
UTF-16BE encoding of u
at the
end of buffer b
.
- since 4.06.0
val
add_string :
t
->
``string
->
unit
add_string b s
appends the string s
at the end of buffer b
.
val
add_bytes :
t
->
``bytes
->
unit
add_bytes b s
appends the byte sequence s
at the end of buffer b
.
- since 4.02
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 buffer b
.
-
raises Invalid_argument
if
ofs
andlen
do not designate a valid range ofs
.
val
add_subbytes :
t
->
``bytes
->
``int
->
``int
->
unit
add_subbytes b s ofs len
takes len
characters from offset ofs
in
byte sequence s
and appends them at the end of buffer b
.
-
raises Invalid_argument
if
ofs
andlen
do not designate a valid range ofs
. -
since 4.02
val
add_substitute :
t
->
``(``string
->
string)``
->
``string
->
unit
add_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:
-
a non empty sequence of alphanumeric or
_
characters, -
an arbitrary sequence of characters enclosed by a pair of matching parentheses or curly brackets. An escaped
$
character is a$
that immediately follows a backslash character; it then stands for a plain$
. -
raises Not_found
if the closing character of a parenthesized variable cannot be found.
add_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
->
unit
add_channel b ic n
reads at most n
characters from the input channel
ic
and stores them at the end of buffer b
.
-
raises 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. -
raises Invalid_argument
if
len < 0
orlen > Sys.max_string_length
.
Buffers and Sequences
Iterate on the buffer, in increasing order.
The behavior is not specified if the buffer is modified during iteration.
- since 4.07
Iterate on the buffer, in increasing order, yielding indices along chars.
The behavior is not specified if the buffer is modified during iteration.
- since 4.07
Binary encoding of integers
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
->
unit
add_uint8 b i
appends a binary unsigned 8-bit integer i
to b
.
- since 4.08
val
add_int8 :
t
->
``int
->
unit
add_int8 b i
appends a binary signed 8-bit integer i
to b
.
- since 4.08
val
add_uint16_ne :
t
->
``int
->
unit
add_uint16_ne b i
appends a binary native-endian unsigned 16-bit
integer i
to b
.
- since 4.08
val
add_uint16_be :
t
->
``int
->
unit
add_uint16_be b i
appends a binary big-endian unsigned 16-bit integer
i
to b
.
- since 4.08
val
add_uint16_le :
t
->
``int
->
unit
add_uint16_le b i
appends a binary little-endian unsigned 16-bit
integer i
to b
.
- since 4.08
val
add_int16_ne :
t
->
``int
->
unit
add_int16_ne b i
appends a binary native-endian signed 16-bit integer
i
to b
.
- since 4.08
val
add_int16_be :
t
->
``int
->
unit
add_int16_be b i
appends a binary big-endian signed 16-bit integer i
to b
.
- since 4.08
val
add_int16_le :
t
->
``int
->
unit
add_int16_le b i
appends a binary little-endian signed 16-bit integer
i
to b
.
- since 4.08
val
add_int32_ne :
t
->
``int32
->
unit
add_int32_ne b i
appends a binary native-endian 32-bit integer i
to
b
.
- since 4.08
val
add_int32_be :
t
->
``int32
->
unit
add_int32_be b i
appends a binary big-endian 32-bit integer i
to
b
.
- since 4.08
val
add_int32_le :
t
->
``int32
->
unit
add_int32_le b i
appends a binary little-endian 32-bit integer i
to
b
.
- since 4.08
val
add_int64_ne :
t
->
``int64
->
unit
add_int64_ne b i
appends a binary native-endian 64-bit integer i
to
b
.
- since 4.08
val
add_int64_be :
t
->
``int64
->
unit
add_int64_be b i
appends a binary big-endian 64-bit integer i
to
b
.
- since 4.08
val
add_int64_le :
t
->
``int64
->
unit
add_int64_ne b i
appends a binary little-endian 64-bit integer i
to
b
.
- since 4.08