• egg

Traversal

This is a Chicken Scheme egg which contains various list and vector traversal functions. Many of the functions provided by this egg originate from Jeff Siskind's QobiScheme.

overall

The final character of many of these functions denotes the compairson function being used. 'q' compares with 'eq?', 'v' compares with 'eqv?', 'e' with 'equal?', 'p' and the lack of a final character denotes that the function takes a user-provided predicate.

The following documentation uses the following notation: 'l' list, 'n' number, 'v' vector, 'p' procedure (usually a predicate).

Some of the functionality of this egg is provided by other eggs, like srfi-1, with different naming conventions.

lists

[procedure] (countq x l)
[procedure] (countv x l)
[procedure] (counte x l)
[procedure] (countp p x l)
[procedure] (count-if p l)
[procedure] (count-if-not p l)
[procedure] (findq x l)
[procedure] (findv x l)
[procedure] (finde x l)
[procedure] (findp p x l)
[procedure] (find-if p l)
[procedure] (find-if-not p l)
[procedure] (positionq x l)
[procedure] (positionv x l)
[procedure] (positione x l)
[procedure] (position p l)
[procedure] (positionp p x l)
[procedure] (position-if p l)
[procedure] (position-if-not p l)
[procedure] (vector-positione val vector)
[procedure] (remove-if p l)
[procedure] (remove-if-not p l)
[procedure] (removee x l)
[procedure] (removep p x l)
[procedure] (removeq x l)
[procedure] (removev x l)
[procedure] (remove-duplicatesq l)
[procedure] (remove-duplicatesv l)
[procedure] (remove-duplicates p l)
[procedure] (remove-duplicatese x l)
[procedure] (list-set! l i x)
[procedure] (list-insert l i x)
[procedure] (list-remove l i)
[procedure] (list-replace l i x)
[procedure] (equivalence-classesq x)
[procedure] (equivalence-classesv x)
[procedure] (equivalence-classes p x)
[procedure] (equivalence-classese x)
[procedure] (transitive-equivalence-classes p x)
[procedure] (rest l)
[procedure] (but-last l)
[procedure] (sublist list start end)
[procedure] (every-other list)
[procedure] (take-until p l)
[procedure] (drop-until p l)

Misc list manipulation stuff.

[procedure] (group-by key l)

Find equivalence classes of the elements of l that are equal? given output of key.

[procedure] (sort list predicate key)

Merge sort.

[procedure] (lexicographically<? <? =?)
[procedure] (minimal-membersp <? =? l)
[procedure] (unzip l)

Transposes lists.

creation

[procedure] (enumerate n)
[procedure] (enumerate-vector n)

Produce a list or a vector containing 0 through n-1.

assertions

[procedure] (some p l)
[procedure] (some-n p n)
[procedure] (some-vector p v)
[procedure] (every-n p n)
[procedure] (every-vector p v)
[procedure] (one p l . &rest)
[procedure] (one-n p n)
[procedure] (one-vector p v . &rest)
[procedure] (pairwise? p l)

Does p hold on each adjacent pair of elements in l.

traversal

[procedure] (for-each-n f n)
[procedure] (for-each-n-decreasing f n)
[procedure] (map-n f n)
[procedure] (map-n-vector f n)
[procedure] (for-each-from-a-up-to-b f a b)
[procedure] (for-each-m-n f m n)
[procedure] (for-each-m-n-indexed f m n)
[procedure] (for-each-m-n-dec f m n)
[procedure] (map-m-n f m n)
[procedure] (map-m-n-indexed f m n)
[procedure] (for-each-vector f v . &rest)
[procedure] (map-vector f v . &rest)

Like 'vector-map' but take an arbitrary number of vectors.

[procedure] (map-linear f start end n)

Map linearly between 'start' and 'end' in 'n' steps.

[procedure] (reduce-n f i n)
[procedure] (reduce-vector f i v)
[procedure] (map-reduce g i f l . ls)
[procedure] (map-reduce-n g i f n)
[procedure] (map-reduce-vector g i f v . vs)
[procedure] (map-reduce2 g i f l)
[procedure] (map-reduce3 g i f l1 l2)

Reduces are left folds.

[procedure] (for-each-indexed f l)
[procedure] (map-indexed f l)
[procedure] (for-each-indexed-vector f v)
[procedure] (map-indexed-vector f v . &rest)

Passes 'f' both the element and an offset into the list/vector.

[procedure] (map-medial f l key)

'f' is passed each adjacent pair of elements in l after being sorted by the key. Key must return a number given each element of l.

[procedure] (all-pairs l)
[procedure] (map-all-pairs f l)

'f' is passed each adjacent pair of elements in l.

[procedure] (memp p x l)
[procedure] (assp p x alist)

Like memq and assq but take a predicate for comparison.

[procedure] (map-accum f i l)

f will be passed the accumulator and each element of the list.

sets

[procedure] (set-unionq x y)
[procedure] (set-unionv x y)
[procedure] (set-union p x y)
[procedure] (set-unione x y)
[procedure] (set-unionvt x y)
[procedure] (set-differenceq x y)
[procedure] (set-differencev x y)
[procedure] (set-difference p x y)
[procedure] (set-differencee x y)
[procedure] (set-differencevt x y)
[procedure] (set-intersectionq x y)
[procedure] (set-intersectionv x y)
[procedure] (set-intersection p x y)
[procedure] (set-intersectione x y)
[procedure] (set-intersectionvt x y)
[procedure] (set-equalq? x y)
[procedure] (set-equalv? x y)
[procedure] (set-equale? x y)
[procedure] (set-equal? p x y)
[procedure] (subsetq? x y)
[procedure] (subsetv? x y)
[procedure] (subsete? x y)
[procedure] (subset? p x y)
[procedure] (subsetvt? x y)

rings

[procedure] (ring-backward l)
[procedure] (ring-forward l)
[procedure] (ring-forward-between r a b)
[procedure] (ring-forward-to l o)

These manipulate a list while treating it as a ring.

minimizing and maximizing

[procedure] (maximump l)
[procedure] (minimump l)
[procedure] (maximum p l)
[procedure] (minimum p l)
[procedure] (maximum-with-position l)
[procedure] (minimum-with-position l)

p is a function that returns a number.

math

[procedure] (sum l)
[procedure] (sum p n)
[procedure] (sum p l)
[procedure] (product l)
[procedure] (product p n)
[procedure] (product p l)
[procedure] (factorial n)
[procedure] (choose n m)

QobiScheme compatibility

[procedure] (qfind x l)
[procedure] (qcount x l)
[procedure] (qposition x l)
[procedure] (qremove x l)
[procedure] (qremove-duplicates l)
[procedure] (qtopological-sort p l)
[procedure] (qset-difference x y)
[procedure] (qset-intersection x y)
[procedure] (qset-union x y)
[procedure] (qset-equal? x y)
[procedure] (qreduce f l i)
[procedure] (qreduce-vector f v i)
[procedure] (qreduce-n f n i)
[procedure] (qmap-reduce g i f l . ls)
[procedure] (qmap-reduce-n g i f n)
[procedure] (qmap-reduce-vector g i f v . vs)
[procedure] (qequivalence-classes x)
[procedure] (qtransitive-equivalence-classesp p x)
[procedure] (qmaximum l)
[procedure] (qminimum l)
[procedure] (qmaximump l p)
[procedure] (qminimump l p)

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`  Contact Andrei Barbu at andrei@0xab.com.`
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