A collection of functions for operating upon Lists.
β–Œ πŸ“¦ [JSR](https://jsr.io/@nodef/extra-lists), πŸ“¦ [NPM](https://www.npmjs.com/package/@nodef/extra-lists), πŸ“° [Docs](https://jsr.io/@nodef/extra-lists/doc). **Lists** is a pair of key list and value list, with unique keys. It is an an alternative to [Entries]. Unless *entries* are implemented as structs by [v8], lists should be more space efficient. This package includes common functions related to querying **about** lists, **generating** them, **comparing** one with another, finding their **size**, **adding** and **removing** entries, obtaining its **properties**, getting a **part** of it, getting a **subset** entries in it, **finding** an entry in it, performing **functional** operations, **manipulating** it in various ways, **combining** together lists or its sub-entries, of performing **set operations** upon it. All functions except `fromEntries()` take lists as 1st parameter. [v8]: https://v8.dev [Entries]: https://jsr.io/@nodef/extra-lists/doc/~/Entries
```javascript import * as xlists from "jsr:@nodef/extra-lists"; var x = [['a', 'b', 'c', 'd', 'e'], [1, 2, 3, 4, 5]]; xlists.filter(x, v => v % 2 === 1); // β†’ [ [ 'a', 'c', 'e' ], [ 1, 3, 5 ] ] var x = [['a', 'b', 'c', 'd'], [1, 2, -3, -4]]; xlists.some(x, v => v > 10); // β†’ false var x = [['a', 'b', 'c', 'd'], [1, 2, -3, -4]]; xlists.min(x); // β†’ -4 var x = [['a', 'b', 'c'], [1, 2, 3]]; [...xlists.subsets(x)].map(a => [[...a[0]], [...a[1]]]); // β†’ [ // β†’ [ [], [] ], // β†’ [ [ 'a' ], [ 1 ] ], // β†’ [ [ 'b' ], [ 2 ] ], // β†’ [ [ 'a', 'b' ], [ 1, 2 ] ], // β†’ [ [ 'c' ], [ 3 ] ], // β†’ [ [ 'a', 'c' ], [ 1, 3 ] ], // β†’ [ [ 'b', 'c' ], [ 2, 3 ] ], // β†’ [ [ 'a', 'b', 'c' ], [ 1, 2, 3 ] ] // β†’ ] ```

## Index | Property | Description | | ---- | ---- | | [is] | Check if value is lists. | | [keys] | List all keys. | | [values] | List all values. | | [entries] | List all key-value pairs. | | | | | [fromEntries] | Convert lists to entries. | | | | | [size] | Find the size of lists. | | [isEmpty] | Check if lists is empty. | | | | | [compare] | Compare two lists. | | [isEqual] | Check if two lists are equal. | | | | | [get] | Get value at key. | | [getAll] | Gets values at keys. | | [getPath] | Get value at path in nested lists. | | [hasPath] | Check if nested lists has a path. | | [set] | Set value at key. | | [swap] | Exchange two values. | | [remove] | Remove value at key. | | | | | [head] | Get first entry from lists (default order). | | [tail] | Get lists without its first entry (default order). | | [take] | Keep first n entries only (default order). | | [drop] | Remove first n entries (default order). | | | | | [count] | Count values which satisfy a test. | | [countAs] | Count occurrences of values. | | [min] | Find smallest value. | | [minEntry] | Find smallest entry. | | [max] | Find largest value. | | [maxEntry] | Find largest entry. | | [range] | Find smallest and largest values. | | [rangeEntries] | Find smallest and largest entries. | | | | | [subsets] | List all possible subsets. | | [randomKey] | Pick an arbitrary key. | | [randomValue] | Pick an arbitrary value. | | [randomEntry] | Pick an arbitrary entry. | | [randomSubset] | Pick an arbitrary subset. | | | | | [has] | Check if lists has a key. | | [hasValue] | Check if lists has a value. | | [hasEntry] | Check if lists has an entry. | | [hasSubset] | Check if lists has a subset. | | [find] | Find first value passing a test (default order). | | [findAll] | Find values passing a test. | | [search] | Finds key of an entry passing a test. | | [searchAll] | Find keys of entries passing a test. | | [searchValue] | Find a key with given value. | | [searchValueAll] | Find keys with given value. | | | | | [forEach] | Call a function for each value. | | [some] | Check if any value satisfies a test. | | [every] | Check if all values satisfy a test. | | [map] | Transform values of entries. | | [reduce] | Reduce values of entries to a single value. | | [filter] | Keep entries which pass a test. | | [filterAt] | Keep entries with given keys. | | [reject] | Discard entries which pass a test. | | [rejectAt] | Discard entries with given keys. | | [flat] | Flatten nested lists to given depth. | | [flatMap] | Flatten nested lists, based on map function. | | [zip] | Combine matching entries from all lists. | | | | | [partition] | Segregate values by test result. | | [partitionAs] | Segregate entries by similarity. | | [chunk] | Break lists into chunks of given size. | | | | | [concat] | Append entries from all lists, preferring last. | | [join] | Join lists together into a string. | | | | | [isDisjoint] | Check if lists have no common keys. | | [unionKeys] | Obtain keys present in any lists. | | [union] | Obtain entries present in any lists. | | [intersection] | Obtain entries present in both lists. | | [difference] | Obtain entries not present in another lists. | | [symmetricDifference] | Obtain entries not present in both lists. |

## References - [What is the most efficient way to deep clone an object in JavaScript?](https://stackoverflow.com/a/122704/1413259) - [structuredClone() global function : MDN Web Docs](https://developer.mozilla.org/en-US/docs/Web/API/structuredClone) - [Attain vs. Obtain: What’s The Difference? : Dictionary.com](https://www.dictionary.com/e/attain-vs-obtain/) - [Acronyms in CamelCase [closed]](https://stackoverflow.com/q/15526107/1413259)

[![](https://raw.githubusercontent.com/qb40/designs/gh-pages/0/image/11.png)](https://wolfram77.github.io)
[![ORG](https://img.shields.io/badge/org-nodef-green?logo=Org)](https://nodef.github.io) ![](https://ga-beacon.deno.dev/G-RC63DPBH3P:SH3Eq-NoQ9mwgYeHWxu7cw/github.com/nodef/extra-lists) [is]: https://jsr.io/@nodef/extra-lists/doc/~/is [keys]: https://jsr.io/@nodef/extra-lists/doc/~/keys [values]: https://jsr.io/@nodef/extra-lists/doc/~/values [entries]: https://jsr.io/@nodef/extra-lists/doc/~/entries [fromEntries]: https://jsr.io/@nodef/extra-lists/doc/~/fromEntries [size]: https://jsr.io/@nodef/extra-lists/doc/~/size [isEmpty]: https://jsr.io/@nodef/extra-lists/doc/~/isEmpty [compare]: https://jsr.io/@nodef/extra-lists/doc/~/compare [isEqual]: https://jsr.io/@nodef/extra-lists/doc/~/isEqual [get]: https://jsr.io/@nodef/extra-lists/doc/~/get [getAll]: https://jsr.io/@nodef/extra-lists/doc/~/getAll [getPath]: https://jsr.io/@nodef/extra-lists/doc/~/getPath [hasPath]: https://jsr.io/@nodef/extra-lists/doc/~/hasPath [set]: https://jsr.io/@nodef/extra-lists/doc/~/set [swap]: https://jsr.io/@nodef/extra-lists/doc/~/swap [remove]: https://jsr.io/@nodef/extra-lists/doc/~/remove [head]: https://jsr.io/@nodef/extra-lists/doc/~/head [tail]: https://jsr.io/@nodef/extra-lists/doc/~/tail [take]: https://jsr.io/@nodef/extra-lists/doc/~/take [drop]: https://jsr.io/@nodef/extra-lists/doc/~/drop [count]: https://jsr.io/@nodef/extra-lists/doc/~/count [countAs]: https://jsr.io/@nodef/extra-lists/doc/~/countAs [min]: https://jsr.io/@nodef/extra-lists/doc/~/min [minEntry]: https://jsr.io/@nodef/extra-lists/doc/~/minEntry [max]: https://jsr.io/@nodef/extra-lists/doc/~/max [maxEntry]: https://jsr.io/@nodef/extra-lists/doc/~/maxEntry [range]: https://jsr.io/@nodef/extra-lists/doc/~/range [rangeEntries]: https://jsr.io/@nodef/extra-lists/doc/~/rangeEntries [subsets]: https://jsr.io/@nodef/extra-lists/doc/~/subsets [randomKey]: https://jsr.io/@nodef/extra-lists/doc/~/randomKey [randomValue]: https://jsr.io/@nodef/extra-lists/doc/~/randomValue [randomEntry]: https://jsr.io/@nodef/extra-lists/doc/~/randomEntry [randomSubset]: https://jsr.io/@nodef/extra-lists/doc/~/randomSubset [has]: https://jsr.io/@nodef/extra-lists/doc/~/has [hasValue]: https://jsr.io/@nodef/extra-lists/doc/~/hasValue [hasEntry]: https://jsr.io/@nodef/extra-lists/doc/~/hasEntry [hasSubset]: https://jsr.io/@nodef/extra-lists/doc/~/hasSubset [find]: https://jsr.io/@nodef/extra-lists/doc/~/find [findAll]: https://jsr.io/@nodef/extra-lists/doc/~/findAll [search]: https://jsr.io/@nodef/extra-lists/doc/~/search [searchAll]: https://jsr.io/@nodef/extra-lists/doc/~/searchAll [searchValue]: https://jsr.io/@nodef/extra-lists/doc/~/searchValue [searchValueAll]: https://jsr.io/@nodef/extra-lists/doc/~/searchValueAll [forEach]: https://jsr.io/@nodef/extra-lists/doc/~/forEach [some]: https://jsr.io/@nodef/extra-lists/doc/~/some [every]: https://jsr.io/@nodef/extra-lists/doc/~/every [map]: https://jsr.io/@nodef/extra-lists/doc/~/map [reduce]: https://jsr.io/@nodef/extra-lists/doc/~/reduce [filter]: https://jsr.io/@nodef/extra-lists/doc/~/filter [filterAt]: https://jsr.io/@nodef/extra-lists/doc/~/filterAt [reject]: https://jsr.io/@nodef/extra-lists/doc/~/reject [rejectAt]: https://jsr.io/@nodef/extra-lists/doc/~/rejectAt [flat]: https://jsr.io/@nodef/extra-lists/doc/~/flat [flatMap]: https://jsr.io/@nodef/extra-lists/doc/~/flatMap [zip]: https://jsr.io/@nodef/extra-lists/doc/~/zip [partition]: https://jsr.io/@nodef/extra-lists/doc/~/partition [partitionAs]: https://jsr.io/@nodef/extra-lists/doc/~/partitionAs [chunk]: https://jsr.io/@nodef/extra-lists/doc/~/chunk [concat]: https://jsr.io/@nodef/extra-lists/doc/~/concat [join]: https://jsr.io/@nodef/extra-lists/doc/~/join [isDisjoint]: https://jsr.io/@nodef/extra-lists/doc/~/isDisjoint [unionKeys]: https://jsr.io/@nodef/extra-lists/doc/~/unionKeys [union]: https://jsr.io/@nodef/extra-lists/doc/~/union [intersection]: https://jsr.io/@nodef/extra-lists/doc/~/intersection [difference]: https://jsr.io/@nodef/extra-lists/doc/~/difference [symmetricDifference]: https://jsr.io/@nodef/extra-lists/doc/~/symmetricDifference