extra-lists.web

Lists is a pair of key list and value list, with unique keys.

All functions except from*() take lists as 1st parameter. Lists are an an alternative to entries, represented as a pair of keys, values. Unless entries are implemented as structs by v8, lists should be more efficient.

Methods as separate packages:

• @extra-lists/find: use rollup to bundle this es module.
• @extra-lists/find.min: use in browser (browserify, uglify-js).

Stability: Experimental.

const lists = require('extra-lists');
// import * as lists from 'extra-lists';
// import * as lists from 'https://unpkg.com/extra-lists@2.2.2/index.mjs'; (deno)

var x = [['a', 'b', 'c', 'd', 'e'], [1, 2, 3, 4, 5]];
lists.filter(x, v => v % 2 === 1);
// [ [ 'a', 'c', 'e' ], [ 1, 3, 5 ] ]

var x = [['a', 'b', 'c', 'd'], [1, 2, -3, -4]];
lists.some(x, v => v > 10);
// false

var x = [['a', 'b', 'c', 'd'], [1, 2, -3, -4]];
lists.min(x);
// [ 'd', -4 ]

var x = [['a', 'b', 'c'], [1, 2, 3]];
[...lists.subsets(x)].map(a => [[...a[0]], [...a[1]]]);
// [
//   [ [], [] ],
//   [ [ 'a' ], [ 1 ] ],
//   [ [ 'b' ], [ 2 ] ],
//   [ [ 'a', 'b' ], [ 1, 2 ] ],
//   [ [ 'c' ], [ 3 ] ],
//   [ [ 'a', 'c' ], [ 1, 3 ] ],
//   [ [ 'b', 'c' ], [ 2, 3 ] ],
//   [ [ 'a', 'b', 'c' ], [ 1, 2, 3 ] ]
// ]

Index

Method	Action
is	Checks if value is lists.
get	Gets value at key.
set	Sets value at key.
remove	Deletes an entry.
swap	Exchanges two values.
size	Gets size of lists.
head	Gets first entry.
take	Keeps first n entries only.
shift	Removes first entry.
fromEntries	Creates lists from entries.
concat	Appends entries from all lists.
flat	Flattens nested lists to given depth.
chunk	Breaks lists into chunks of given size.
filterAt	Gets lists with given keys.
map	Updates values based on map function.
filter	Keeps entries which pass a test.
reduce	Reduces values to a single value.
range	Finds smallest and largest entries.
count	Counts values which satisfy a test.
partition	Segregates values by test result.
cartesianProduct	Lists cartesian product of lists.
some	Checks if any value satisfies a test.
zip	Combines matching entries from all lists.
union	Gives lists present in any lists.
intersection	Gives entries present in both lists.
difference	Gives entries of lists not present in another.
symmetricDifference	Gives entries not present in both lists.
isDisjoint	Checks if lists have no common keys.
key	Picks an arbitrary key.
value	Picks an arbitrary value.
entry	Picks an arbitrary entry.
subset	Picks an arbitrary submap.
isEmpty	Checks if lists is empty.
isEqual	Checks if two lists are equal.
compare	Compares two lists.
find	Finds a value passing a test.
search	Finds key of an entry passing a test.
scanWhile	Finds key of first entry not passing a test.