byte-blob

byte-blob aims to provide a SRFI-1-inspired API for manipulating byte vectors encoded as blobs. In addition it borrows inspiration from the Haskell bytestring library (http://hackage.haskell.org/package/bytestring-0.9.2.1/docs/Data-ByteString.html).

Library Procedures

Predicates

(byte-blob? X) => BOOL

Returns #t if the given object is a byte-blob, #f otherwise.

(byte-blob-empty? BYTE-BLOB) => BOOL

Returns #t if the given byte-blob is empty, #f otherwise.

Constructors

(byte-blob-empty) => BYTE-BLOB

Returns an empty byte-blob.

(byte-blob-replicate N V) => BYTE-BLOB

Returns a byte-blob of length N, where each element is V.

(byte-blob-cons X BYTE-BLOB) => BYTE-BLOB

Analogous to list cons, but of complexity O(N), as it requires copying the elements of the byte-blob argument.

(blob->byte-blob BLOB) => BYTE-BLOB

Returns a byte-blob containing the elements of the given blob.

(list->byte-blob LIST) => BYTE-BLOB

Returns a byte-blob containing the elements of LIST.

(string->byte-blob STRING) => BYTE-BLOB

Returns a byte-blob containing the elements of STRING.

Accessors

(byte-blob-length BYTE-BLOB) => INTEGER

Returns the number of elements contained in the given byte-blob.

(byte-blob-car BYTE-BLOB) => X

Returns the first element of a byte-blob. The argument byte-blob must be non-empty, or an exception will be thrown.

(byte-blob-cdr BYTE-BLOB) => BYTE-BLOB

Returns a byte-blob that contains the elements after the first element of the given byte-blob. The argument byte-blob must be non-empty, or an exception will be thrown.

(byte-blob-ref BYTE-BLOB I) => BYTE

Returns the i-th element of the given byte-blob as a signed byte.

(byte-blob-uref BYTE-BLOB I) => BYTE

Returns the i-th element of the given byte-blob as an unsigned byte.

Transformers

(byte-blob-set! BYTE-BLOB I V) => VOID

Sets the i-th element of the given byte-blob to the signed byte V.

(byte-blob-uset! BYTE-BLOB I V) => VOID

Sets the i-th element of the given byte-blob to the unsigned byte V.

(byte-blob-append BYTE-BLOB BYTE-BLOB) => BYTE-BLOB

Appends two byte-blobs together.

(byte-blob-reverse BYTE-BLOB) => BYTE-BLOB

Returns a byte-blob that contains the elements of the given byte-blob in reverse order.

(byte-blob-intersperse BYTE-BLOB BYTE) => BYTE-BLOB

Returns a byte-blob with the given byte placed between the elements of the given byte-blob.

(byte-blob-map F BYTE-BLOB) => BYTE-BLOB

Returns a byte-blob obtained by applying F to each element of the given byte-blob.

(byte-blob->blob BYTE-BLOB) => BLOB

Returns the underlying Scheme blob object.

(byte-blob->list BYTE-BLOB [F]) => LIST

Returns a list containing the elements of the given byte-blob. If procedure F is provided as a second argument, it is applied to every element of the returned list.

(byte-blob->string BYTE-BLOB) => STRING

Returns a string containing the elements of the given byte-blob.

Subsequences

(byte-blob-take BYTE-BLOB N) => BYTE-BLOB

Returns the prefix of the given byte-blob of length N.

(byte-blob-drop BYTE-BLOB N) => BYTE-BLOB

Returns the suffix of the given byte-blob after the first N elements.

(byte-blob-span BYTE-BLOB START END) => BYTE-BLOB

Returns the subsequence of the give byte-blob from position START to position END.

Fold

(byte-blob-fold-left F INIT BYTE-BLOB) => VALUE
(byte-blob-fold-right F INIT BYTE-BLOB) => VALUE

Given a procedure of two arguments, a starting value, and a byte-blob, reduces the byte-blob using the supplied procedure, from left to right, or right to left, respectively.

Find

(byte-blob-find NEEDLE HAYSTACK) => LIST

Finds all non-overlapping instances of the byte-blob NEEDLE in the byte-blob HAYSTACK. The first element of the returned list is the prefix of HAYSTACK prior to any matches of NEEDLE. The second is a list of lists.

The first element of each pair in the list is a span from the beginning of a match to the beginning of the next match, while the second is a span from the beginning of the match to the end of the input.

I/O

(file->byte-blob FILENAME [MODE]) => BYTE-BLOB

Returns a byte-blob with the contents of the given file.

MODE is an optional argument that can be one of #:text or #:binary to specify text or binary mode on Windows.

(byte-blob-read PORT N) => BYTE-BLOB

Reads a byte-blob of length N from the given port. Currently, the port must support the port->fileno procedure, which means that string ports are not supported (in that particular case, procedure {{string->byte-blob}} can be used for converting strings to byte blobs).

(byte-blob-write PORT BYTE-BLOB) => UNDEFINED

Writes the given byte-blob to the given port. Currently, the port must support the port->fileno procedure, which means that string ports are not supported (in that particular case, procedure {{string->byte-blob}} can be used for converting strings to byte blobs).

SRFI-4 transformers

(u8vector->byte-blob U8VECTOR) => BYTE-BLOB
(s8vector->byte-blob S8VECTOR) => BYTE-BLOB
(u16vector->byte-blob U16VECTOR) => BYTE-BLOB
(s16vector->byte-blob S16VECTOR) => BYTE-BLOB
(u32vector->byte-blob U32VECTOR) => BYTE-BLOB
(s32vector->byte-blob S32VECTOR) => BYTE-BLOB
(f32vector->byte-blob F32VECTOR) => BYTE-BLOB
(f64vector->byte-blob F64VECTOR) => BYTE-BLOB
(byte-blob->u8vector BYTE-BLOB) => U8VECTOR
(byte-blob->s8vector BYTE-BLOB) => S8VECTOR
(byte-blob->u16vector BYTE-BLOB) => U16VECTOR
(byte-blob->s16vector BYTE-BLOB) => S16VECTOR
(byte-blob->u32vector BYTE-BLOB) => U32VECTOR
(byte-blob->s32vector BYTE-BLOB) => S32VECTOR
(byte-blob->f32vector BYTE-BLOB) => F32VECTOR
(byte-blob->f64vector BYTE-BLOB) => F64VECTOR

License

Based on ideas from the Haskell [[http://www.cse.unsw.edu.au/~dons/fps.html|bytestring]] library.

The code for byte-blob-find is based on code from the Haskell Text library by Tom Harper and Bryan O'Sullivan.

Copyright 2009-2020 Ivan Raikov, Dan Thedens.

This program is free software: you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

A full copy of the GPL license can be found at http://www.gnu.org/licenses/.