Rationale
This module allows to acces some sequence types, in particular lists, pairs, vectors and strings with a common interface. The number of sequence types handled can be enhanced. The egg is not as complete and sophisticated as Felix' sequences egg, but quite usable. In particular, it is sufficient for use in Paul Graham's dbind implementation, cf. On Lisp, p. 232, which is the workhorse of my bindings egg.
API
sequence-db
- sequence-dbprocedure
- sequence-db seqprocedure
- sequence-db seq? seq-length seq-ref seq-tail seq-maker #!rest pos?procedure
database processing: the first resets the database to the standard with lists, pairs, vectors and strings, the second returns the vector of handlers as well as the discriminator, the third adds a new database record either at the end or before the pos? discriminator. A record cosists of a discriminator, seq?, and a vector with items seq-lenth, seq-ref, seq-tail and seq-maker patterned after vectors. Note, that the last record can handle atoms, albeit it is not a sequence.
sequence?
- sequence? xprocedure
type predicate.
seq-length
- seq-length seqprocedure
returns the length of a sequences
seq-ref
- seq-ref seq kprocedure
returns the item of seq at position k
seq-tail
- seq-tail seq kprocedure
reuturns the subsequence of seq starting at position k. Note that k might be equal to (seq-length seq), returning the sentinel of empty sequence
seq-maker
- seq-maker seqprocedure
returns the maker, like list or vector, to create new sequences of the same type as seq.
seq-nil
- seq-nil seqprocedure
returns the sentinel of pairs or empty sequences
seq-pseudo?
- seq-pseudo? xprocedure
checks, if the sequence is pseudo, i.e. a pair. This is needed to handle pairs like other sequences.
sequence->list
- sequence->list seqprocedure
type transformer
seq-reverse
- seq-reverse seqprocedure
returns a new sequence with items reversed
subseq
- subseq seq iprocedure
- subseq seq i jprocedure
creates a new sequence of the same type as seq consisting of seq's items from i included and j excluded
seq-filter
- seq-filter ok? seqprocedure
returns two subsequences of the same type as seq of items passed or not passed by the ok? test
seq-memp
- seq-memp ok? seqprocedure
returns a new sequence of seq's type of items from seq starting at the first item which passes the ok? test, or #f
seq-append
- seq-append seq #!rest seqsprocedure
appends the items of all argument sequences, which must be of the same type as seq and in case of pairs, the same sentinel
seq-map
- seq-map fn seq #!rest seqsprocedure
maps the argument sequences up to the shortest length. All sequences must be of the same type, and in case of pairs, must have the same sentinels
seq-for-each
- seq-for-each proc seq #!rest seqsprocedure
applies proc to each item of seq and seqs up to the shortest length. The sequences might be of different type
seq-ref*
- seq-ref* seq indprocedure
references the value of a nested sequence at appropriate index list: with index '(0) it returns (seq-ref seq 0), with index '(1 0) it returns (seq-ref (seq-ref seq 1) 0)
seq-flat?
- seq-flat? seqprocedure
is the sequence seq flat?
seq-length*
- seq-length* seqprocedure
counts the number of items in a nested sequence seq
seq-map*
- seq-map* fn seqprocedure
deep map: maps all items of a nested sequence seq with function fn
simple-sequences
- simple-sequencesprocedure
- simple-sequences symprocedure
with sym: documentation of exported symbol without sym: list of exported symbols
Examples
(import simple-sequences)
(sequence-db '())
;-> (vector length list-ref list-tail list)
(sequence-db #())
;-> (vector vector-length vector-ref subvector vector)
(sequence-db "")
;-> (vector string-length string-ref substring string)
(seq-length '())
;-> 0
(seq-length #())
;-> 0
(seq-length "")
;-> 0
(seq-length '(1 . 2))
;-> 1
(seq-length 1)
;-> 0
(seq-ref '(0 1 2 3) 1)
;-> 1
(seq-ref #(0 1 2 3) 1)
;-> 1
(seq-ref "0123" 1)
;-> 1
(seq-ref '(0 1 2 . 3) 1)
;-> 1
(seq-tail '(0 1 2 3 4) 1)
;-> (quote (1 2 3 4))
(seq-tail #(0 1 2 3 4) 1)
;-> #(1 2 3 4)
(seq-tail "01234" 1)
;-> 1234
(seq-tail '(0 1 2 3 . 4) 1)
;-> (quote (1 2 3 . 4))
(seq-tail '(0 1 2 3 . 4) 4)
;-> 4
(seq-tail 1 0)
;-> 1
(sequence? 1)
;-> #f
(length (sequence-db))
;-> 5
(list-ref
(sequence-db
number?
(lambda (x) 0)
(lambda (x i) (error))
(lambda (x i) x)
(lambda (x) x))
4)
;-> number?
(car (sequence-db
integer?
(lambda (x) 0)
(lambda (x i) (error))
(lambda (x i) x)
(lambda (x) x)
list?))
;-> integer?
(length (sequence-db))
;-> 5
(condition-case (seq-ref 1 0) ((exn) "out of range"))
;-> out of range
(seq-tail 1 0)
;-> 1
(condition-case (seq-tail 1 1) ((exn) "out of range"))
;-> out of range
(sequence->list '(0 1 2 . 3))
;-> (quote (0 1 2))
(seq-maker str)
;-> string
(subseq str 1)
;-> 123
(subseq str 1 3)
;-> 12
(subseq pls 1 3)
;-> (quote (1 2 . 3))
(seq-nil str)
;->
(seq-nil pls)
;-> 3
(seq-pseudo? pls)
;-> #t
(seq-pseudo? lst)
;-> #f
(seq-reverse "abc")
;-> cba
(seq-reverse '(1 2 3 . 0))
;-> (quote (3 2 1 . 0))
(receive (odd even) (seq-filter odd? vec) (list odd even))
;-> (quote (#(1 3) #(0 2)))
(receive (odd even) (seq-filter odd? pls) (list odd even))
;-> (quote ((1 . 3) (0 2 . 3)))
(seq-memp odd? vec)
;-> #(1 2 3)
(seq-memp odd? pls)
;-> (quote (1 2 . 3))
(seq-memp (lambda (s) (char=? s #\2)) str)
;-> 23
(seq-append #(1 2 3) #(10 20 30))
;-> #(1 2 3 10 20 30)
(seq-append '(1 2 3 . 0) '(10 20 30 . 0))
;-> (quote (1 2 3 10 20 30 . 0))
(seq-append "a" "b" "c" "d" "e")
;-> abcde
(seq-map add1 #(0 1 2))
;-> #(1 2 3)
(seq-map add1 '(0 1 2 . 0))
;-> (quote (1 2 3 . 0))
(seq-map + #(1 2 3) #(10 20 30 40))
;-> #(11 22 33)
(seq-map + '(1 2 . 0) '(10 20 . 0))
;-> (quote (11 22 . 0))
(condition-case (seq-map + '(1 2 . 3) '(10 20 . 30)) ((exn) "different nils"))
;-> different nils
(seq-ref* '(1 #(2 3)) '(1 0))
;-> 2
(seq-ref* '(0 #(1 "23")) '(1 1 1))
;-> 3
(seq-ref* '(0 #(1 "23")) '(1 0))
;-> 1
(seq-ref* '(0 #(1 "23")) '(1 1))
;-> 23
(seq-flat? #(1 2 3))
;-> #t
(seq-flat? '(1 #(2 3)))
;-> #f
(seq-length* '((2 (3 #(4) 5) 1) 0))
;-> 6
(seq-length* '(1 #(2 "3")))
;-> 3
(seq-length* '(((((0))))))
;-> 1
(seq-map* add1 '(((2) 1) 0))
;-> (quote (((3) 2) 1))
(seq-map* add1 '(0 #(1 2)))
;-> (quote (1 #(2 3)))
(seq-map* add1 '(0 (1 2 . 3)))
;-> (quote (1 (2 3 . 3)))
(seq-map* add1 '(0 (1 (2 . 3))))
;-> (quote (1 (2 (3 . 3))))
(seq-map* add1 '(0 (1 (2 . 3) . 0)))
;-> (quote (1 (2 (3 . 3) . 0)))
Requirements
None
Last update
Nov 22, 2020
Author
Juergen Lorenz
Repository
This egg is hosted on the CHICKEN Subversion repository:
https://anonymous@code.call-cc.org/svn/chicken-eggs/release/5/simple-sequences
If you want to check out the source code repository of this egg and you are not familiar with Subversion, see this page.
License
Copyright (c) 2020 , Juergen Lorenz, ju (at) jugilo (dot) de All rights reserved.
Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:
Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution. Neither the name of the author nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
Version history
- 1.0
- Initial check in