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byte-blob

Description

byte-blob is a library of routines for manipulating byte vectors encoded as blobs.

Library Procedures

Predicates

[procedure] (byte-blob? X) => BOOL

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

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

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

Constructors

[procedure] (byte-blob-empty) => BYTE-BLOB

Returns an empty byte-blob.

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

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

[procedure] (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.

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

Returns a byte-blob containing the elements of LIST.

[procedure] (string->byte-blob STRING) => BYTE-BLOB

Returns a byte-blob containing the elements of STRING.

Accessors

<procedure(byte-blob-length BYTE-BLOB) => INTEGER</procedure>

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

[procedure] (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.

[procedure] (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.

Transformers

[procedure] (byte-blob-append BYTE-BLOB BYTE-BLOB) => BYTE-BLOB

Appends two byte-blobs together.

[procedure] (byte-blob-reverse BYTE-BLOB) => BYTE-BLOB

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

[procedure] (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.

[procedure] (byte-blob-map F BYTE-BLOB) => BYTE-BLOB

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

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

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

[procedure] (byte-blob->string BYTE-BLOB) => STRING

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

Subsequences

[procedure] (byte-blob-take BYTE-BLOB N) => BYTE-BLOB

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

[procedure] (byte-blob-drop BYTE-BLOB N) => BYTE-BLOB

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

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

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

Fold

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

[procedure] (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

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

Reads a byte-blob of length N from the given port.

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

Writes the given byte-blob to the given port.

SRFI-4 transformers

Version History

License

Based on ideas from the Haskell 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 Ivan Raikov and the Okinawa Institute of Science and Technology.
 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/>.