extra-object/index.d.ts

A collection of methods for working with Objects.

/**
 * Entries is a list of key-value pairs, with unique keys (indices).
 * [📘](https://github.com/nodef/extra-object/wiki/Entries)
 */
type Entries = Iterable<[string, any]>;
/**
 * Lists is a pair of key list and value list, with unique keys (indices).
 * [📘](https://github.com/nodef/extra-object/wiki/Lists)
 */
type Lists = [Iterable<string>, Iterable<any>];
/**
 * Handle reading of a single value.
 * [📘](https://github.com/nodef/extra-object/wiki/ReadFunction)
 * @returns value
 */
type ReadFunction<T> = () => T;
/**
 * Handle combining of two values.
 * [📘](https://github.com/nodef/extra-object/wiki/CombineFunction)
 * @param a a value
 * @param b another value
 * @returns combined value
 */
type CombineFunction = (a: any, b: any) => any;
/**
 * Handle comparison of two values.
 * [📘](https://github.com/nodef/extra-object/wiki/CompareFunction)
 * @param a a value
 * @param b another value
 * @returns a<b: -ve, a=b: 0, a>b: +ve
 */
type CompareFunction = (a: any, b: any) => number;
/**
 * Handle processing of values in an object.
 * [📘](https://github.com/nodef/extra-object/wiki/ProcessFunction)
 * @param v value in object
 * @param k key of value in object
 * @param x object containing the value
 */
type ProcessFunction = (v: any, k: string, x: object) => void;
/**
 * Handle selection of entries in an object.
 * [📘](https://github.com/nodef/extra-object/wiki/TestFunction)
 * @param v value in object
 * @param k key of value in object
 * @param x object containing the value
 * @returns selected?
 */
type TestFunction = (v: any, k: string, x: object) => boolean;
/**
 * Handle transformation of a value to another.
 * [📘](https://github.com/nodef/extra-object/wiki/MapFunction)
 * @param v value in object
 * @param k key of value in object
 * @param x object containing the value
 * @returns transformed value
 */
type MapFunction = (v: any, k: string, x: object) => any;
/**
 * Handle reduction of multiple values into a single value.
 * [📘](https://github.com/nodef/extra-object/wiki/ReduceFunction)
 * @param acc accumulator (temporary result)
 * @param v value in object
 * @param k key of value in object
 * @param x object containing the value
 * @returns reduced value
 */
type ReduceFunction = (acc: any, v: any, k: string, x: object) => any;
/**
 * Handle ending of a combined object.
 * [📘](https://github.com/nodef/extra-object/wiki/EndFunction)
 * @param dones iᵗʰ object done?
 * @returns combined object done?
 */
type EndFunction = (dones: boolean[]) => boolean;
/**
 * Check if value is an object.
 * [📘](https://github.com/nodef/extra-object/wiki/is)
 * @param v a value
 * @returns v is an object?
 */
declare function is(v: any): v is object;
/**
 * List all keys.
 * [📘](https://github.com/nodef/extra-object/wiki/keys)
 * @param x an object
 * @returns k₀, k₁, ... | [kᵢ, vᵢ] ∈ x
 */
declare function keys(x: object): Iterable<string>;
/**
 * List all values.
 * [📘](https://github.com/nodef/extra-object/wiki/values)
 * @param x an object
 * @returns v₀, v₁, ... | [kᵢ, vᵢ] ∈ x
 */
declare function values(x: object): Iterable<any>;
/**
 * List all key-value pairs.
 * [📘](https://github.com/nodef/extra-object/wiki/entries)
 * @param x an object
 * @returns [k₀, v₀], [k₁, v₁], ... | [kᵢ, vᵢ] ∈ x
 */
declare function entries(x: object): Entries;
/**
 * Convert entries to object.
 * [📘](https://github.com/nodef/extra-object/wiki/fromEntries)
 * @param x entries
 * @returns x as object
 */
declare function fromEntries(x: Entries): object;
/**
 * Convert lists to object.
 * [📘](https://github.com/nodef/extra-object/wiki/fromLists)
 * @param x lists, i.e. [keys, values]
 * @returns x as object
 */
declare function fromLists(x: Lists): object;
/**
 * Compare two objects.
 * [📘](https://github.com/nodef/extra-object/wiki/compare)
 * @param x an object
 * @param y another object
 * @param fc compare function (a, b)
 * @param fm map function (v, k, x)
 * @returns x=y: 0, otherwise: -ve/+ve
 */
declare function compare(x: object, y: object, fc?: CompareFunction | null, fm?: MapFunction | null): number;
/**
 * Check if two objects are equal.
 * [📘](https://github.com/nodef/extra-object/wiki/isEqual)
 * @param x an object
 * @param y another object
 * @param fc compare function (a, b)
 * @param fm map function (v, k, x)
 * @returns fm(x[kᵢ]) ≈ fm(y[kᵢ]) ∀ kᵢ ∈ x, y
 */
declare function isEqual(x: object, y: object, fc?: CompareFunction | null, fm?: MapFunction | null): boolean;
/**
 * Get the number of keys in an object.
 * [📘](https://github.com/nodef/extra-object/wiki/size)
 * @param x an object
 * @returns |x|
 */
declare function size(x: object): number;

/**
 * Check if an object is empty.
 * [📘](https://github.com/nodef/extra-object/wiki/isEmpty)
 * @param x an object
 * @returns |x| = 0?
 */
declare function isEmpty(x: object): boolean;
/**
 * Get value at specified key.
 * [📘](https://github.com/nodef/extra-object/wiki/get)
 * @param x an object
 * @param k key
 * @returns x[k]
 */
declare function get(x: object, k: string): any;
/**
 * Get values at keys.
 * [📘](https://github.com/nodef/extra-object/wiki/getAll)
 * @param x an object
 * @param ks keys
 * @returns [x[k], x[l], ...] | [k, l, ...] = ks
 */
declare function getAll(x: object, ks: string[]): any[];
/**
 * Get value at path in a nested object.
 * [📘](https://github.com/nodef/extra-object/wiki/getPath)
 * @param x a nested object
 * @param p path
 * @returns x[k₀][k₁][...] | [k₀, k₁, ...] = p
 */
declare function getPath(x: object, p: string[]): any;
/**
 * Check if nested object has a path.
 * [📘](https://github.com/nodef/extra-object/wiki/hasPath)
 * @param x a nested object
 * @param p path
 * @returns x[k₀][k₁][...] exists? | [k₀, k₁, ...] = p
 */
declare function hasPath(x: object, p: string[]): boolean;
/**
 * Set value at specified key.
 * [📘](https://github.com/nodef/extra-object/wiki/set)
 * @param x an object
 * @param k key
 * @param v value
 * @returns x' | x' = x; x'[k] = v
 */
declare function set(x: object, k: string, v: any): object;
/**
 * Set value at specified key.
 * [📘](https://github.com/nodef/extra-object/wiki/set$)
 * @param x an object (updated)
 * @param k key
 * @param v value
 * @returns x | x[k] = v
 */
declare function set$(x: object, k: string, v: any): object;
/**
 * Set value at path in a nested object.
 * [📘](https://github.com/nodef/extra-object/wiki/setPath$)
 * @param x a nested object (updated)
 * @param p path
 * @param v value
 * @returns x | x[k₀][k₁][...] = v; [k₀, k₁, ...] = p
 */
declare function setPath$(x: object, p: string[], v: any): any;
/**
 * Exchange two values in an object.
 * [📘](https://github.com/nodef/extra-object/wiki/swap)
 * @param x an object
 * @param k a key
 * @param l another key
 * @returns x' | x' = x; x'[k] = x[l]; x'[l] = x[k]
 */
declare function swap(x: object, k: string, l: string): object;
/**
 * Exchange two values in an object.
 * [📘](https://github.com/nodef/extra-object/wiki/swap$)
 * @param x an object (updated)
 * @param k a key
 * @param l another key
 * @returns x | x[i] ↔ x[j]
 */
declare function swap$(x: object, k: string, l: string): object;
/**
 * Remove an entry from object.
 * [📘](https://github.com/nodef/extra-object/wiki/remove)
 * @param x an object
 * @param k key
 * @returns x \\: [k]
 */
declare function remove(x: object, k: string): object;
/**
 * Remove an entry from object.
 * [📘](https://github.com/nodef/extra-object/wiki/remove$)
 * @param x an object (updated)
 * @param k key
 * @returns x = x \\: [k]
 */
declare function remove$(x: object, k: string): object;
/**
 * Remove value at path in a nested object.
 * [📘](https://github.com/nodef/extra-object/wiki/removePath$)
 * @param x a nested object (updated)
 * @param p path
 * @returns x = x \\: [k₀][k₁][...] | [k₀, k₁, ...] = p
 */
declare function removePath$(x: object, p: string[]): any;
/**
 * Count values which satisfy a test.
 * [📘](https://github.com/nodef/extra-object/wiki/count)
 * @param x an object
 * @param ft test function (v, k, x)
 * @returns Σtᵢ | tᵢ = 1 if ft(vᵢ) else 0; [kᵢ, vᵢ] ∈ x
 */
declare function count(x: object, ft: TestFunction): number;
/**
 * Count occurrences of values.
 * [📘](https://github.com/nodef/extra-object/wiki/countAs)
 * @param x an object
 * @param fm map function (v, k, x)
 * @returns Map \{value ⇒ count\}
 */
declare function countAs(x: object, fm?: MapFunction | null): Map<any, number>;
/**
 * Find smallest value.
 * [📘](https://github.com/nodef/extra-object/wiki/min)
 * @param x an object
 * @param fc compare function (a, b)
 * @param fm map function (v, k, x)
 * @returns v | v ≤ vᵢ; [kᵢ, vᵢ] ∈ x
 */
declare function min(x: object, fc?: CompareFunction | null, fm?: MapFunction | null): any;
/**
 * Find smallest entry.
 * [📘](https://github.com/nodef/extra-object/wiki/minEntry)
 * @param x an object
 * @param fc compare function (a, b)
 * @param fm map function (v, k, x)
 * @returns [min_key, min_value]
 */
declare function minEntry(x: object, fc?: CompareFunction | null, fm?: MapFunction | null): [string, any];
/**
 * Find largest value.
 * [📘](https://github.com/nodef/extra-object/wiki/max)
 * @param x an object
 * @param fc compare function (a, b)
 * @param fm map function (v, k, x)
 * @returns v | v ≥ vᵢ; [kᵢ, vᵢ] ∈ x
 */
declare function max(x: object, fc?: CompareFunction | null, fm?: MapFunction | null): any;
/**
 * Find largest entry.
 * [📘](https://github.com/nodef/extra-object/wiki/maxEntry)
 * @param x an object
 * @param fc compare function (a, b)
 * @param fm map function (v, k, x)
 * @returns [max_key, max_value]
 */
declare function maxEntry(x: object, fc?: CompareFunction | null, fm?: MapFunction | null): [string, any];
/**
 * Find smallest and largest values.
 * [📘](https://github.com/nodef/extra-object/wiki/range)
 * @param x a map
 * @param fc compare function (a, b)
 * @param fm map function (v, k, x)
 * @returns [min_value, max_value]
 */
declare function range(x: object, fc?: CompareFunction | null, fm?: MapFunction | null): [any, any];
/**
 * Find smallest and largest entries.
 * [📘](https://github.com/nodef/extra-object/wiki/rangeEntries)
 * @param x an object
 * @param fc compare function (a, b)
 * @param fm map function (v, k, x)
 * @returns [min_entry, max_entry]
 */
declare function rangeEntries(x: object, fc?: CompareFunction | null, fm?: MapFunction | null): [[string, any], [string, any]];
/**
 * Gets first entry from object (default order).
 * [📘](https://github.com/nodef/extra-object/wiki/head)
 * @param x an object
 * @param ed default entry
 * @returns [k₀, v₀] if x ≠ Φ else ed | [k₀, v₀] ∈ x
 */
declare function head(x: object, ed?: [string, any]): [string, any];
/**
 * Get object without its first entry (default order).
 * [📘](https://github.com/nodef/extra-object/wiki/tail)
 * @param x an object
 * @returns x \\ \{[k₀, v₀]\} if x ≠ Φ else x | [k₀, v₀] ∈ x
 */
declare function tail(x: object): object;
/**
 * Keep first n entries only (default order).
 * [📘](https://github.com/nodef/extra-object/wiki/take)
 * @param x an object
 * @param n number of entries [1]
 * @returns \{[k₀, v₀], [k₁, v₁], ...\} | [kᵢ, vᵢ] ∈ x and |\{[k₀, v₀], [k₁, v₁], ...\}| ≤ n
 */
declare function take(x: object, n?: number): object;
/**
 * Keep first n entries only (default order).
 * [📘](https://github.com/nodef/extra-object/wiki/take$)
 * @param x an object (updated)
 * @param n number of entries [1]
 * @returns x = \{[k₀, v₀], [k₁, v₁], ...\} | [kᵢ, vᵢ] ∈ x and |\{[k₀, v₀], [k₁, v₁], ...\}| ≤ n
 */
declare function take$(x: object, n?: number): object;
/**
 * Remove first n entries (default order).
 * [📘](https://github.com/nodef/extra-object/wiki/drop)
 * @param x an object
 * @param n number of entries [1]
 * @returns \{[kₙ, vₙ], [kₙ₊₁, vₙ₊₁], ...\} | [kᵢ, vᵢ] ∈ x and |\{[kₙ, vₙ], [kₙ₊₁, vₙ₊₁], ...\}| ≤ max(|x| - n, 0)
 */
declare function drop(x: object, n?: number): object;
/**
 * Remove first n entries (default order).
 * [📘](https://github.com/nodef/extra-object/wiki/drop$)
 * @param x an object (updated)
 * @param n number of entries [1]
 * @returns x = \{[kₙ, vₙ], [kₙ₊₁, vₙ₊₁], ...\} | [kᵢ, vᵢ] ∈ x and |\{[kₙ, vₙ], [kₙ₊₁, vₙ₊₁], ...\}| ≤ max(|x| - n, 0)
 */
declare function drop$(x: object, n?: number): object;
/**
 * List all possible subsets.
 * [📘](https://github.com/nodef/extra-object/wiki/subsets)
 * @param x an object
 * @param n number of entries [-1 ⇒ any]
 * @returns entries selected by bit from 0..2^|x| if n<0; only of length n otherwise
 */
declare function subsets(x: object, n?: number): IterableIterator<object>;
/**
 * Pick an arbitrary key.
 * [📘](https://github.com/nodef/extra-object/wiki/randomKey)
 * @param x an object
 * @param fr random number generator ([0, 1))
 * @returns kᵢ | [kᵢ, vᵢ] ∈ x
 */
declare function randomKey(x: object, fr?: ReadFunction<number> | null): string;

/**
 * Pick an arbitrary entry.
 * [📘](https://github.com/nodef/extra-object/wiki/randomEntry)
 * @param x an object
 * @param fr random number generator ([0, 1))
 * @returns [kᵢ, vᵢ] | [kᵢ, vᵢ] ∈ x
 */
declare function randomEntry(x: object, fr?: ReadFunction<number> | null): [string, any];

/**
 * Pick an arbitrary subset.
 * [📘](https://github.com/nodef/extra-object/wiki/randomSubset)
 * @param x an object
 * @param n number of entries [-1 ⇒ any]
 * @param fr random number generator ([0, 1))
 * @returns \{[kᵢ, vᵢ], [kⱼ, vⱼ], ...\} | [kᵢ, vᵢ], [kⱼ, vⱼ], ... ∈ x; |\{[kᵢ, vᵢ], [kⱼ, vⱼ], ...\}| = |x| if n<0 else n
 */
declare function randomSubset(x: object, n?: number, fr?: ReadFunction<number> | null): object;

/**
 * Check if object has a key.
 * [📘](https://github.com/nodef/extra-object/wiki/has)
 * @param x an object
 * @param k search key
 * @returns [k, *] ∈ x?
 */
declare function has(x: object, k: string): boolean;

/**
 * Check if object has a value.
 * [📘](https://github.com/nodef/extra-object/wiki/hasValue)
 * @param x an object
 * @param v search value
 * @param fc compare function (a, b)
 * @param fm map function (v, k, x)
 * @returns [*, v] ∈ x?
 */
declare function hasValue(x: object, v: any, fc?: CompareFunction | null, fm?: MapFunction | null): boolean;
/**
 * Check if object has an entry.
 * [📘](https://github.com/nodef/extra-object/wiki/hasEntry)
 * @param x an object
 * @param e search entry ([k, v])
 * @param fc compare function (a, b)
 * @param fm map function (v, k, x)
 * @returns [k, v] ∈ x? | [k, v] = e
 */
declare function hasEntry(x: object, e: [string, any], fc?: CompareFunction | null, fm?: MapFunction | null): boolean;
/**
 * Check if object has a subset.
 * [📘](https://github.com/nodef/extra-object/wiki/hasSubset)
 * @param x an object
 * @param y search subset
 * @param fc compare function (a, b)
 * @param fm map function (v, k, x)
 * @returns y ⊆ x?
 */
declare function hasSubset(x: object, y: object, fc?: CompareFunction | null, fm?: MapFunction | null): boolean;
/**
 * Find value of an entry passing a test.
 * [📘](https://github.com/nodef/extra-object/wiki/find)
 * @param x an object
 * @param ft test function (v, k, x)
 * @returns v | ft(v) = true; [k, v] ∈ x
 */
declare function find(x: object, ft: TestFunction): any;
/**
 * Find values of entries passing a test.
 * [📘](https://github.com/nodef/extra-object/wiki/findAll)
 * @param x an object
 * @param ft test function (v, k, x)
 * @returns [vₒ, v₁, ...] | ft(vᵢ) = true; [kᵢ, vᵢ] ∈ x
 */
declare function findAll(x: object, ft: TestFunction): any[];
/**
 * Find key of an entry passing a test.
 * [📘](https://github.com/nodef/extra-object/wiki/search)
 * @param x an object
 * @param ft test function (v, k, x)
 * @returns k | ft(x[k]) passes
 */
declare function search(x: object, ft: TestFunction): string;
/**
 * Find all keys of entries passing a test.
 * [📘](https://github.com/nodef/extra-object/wiki/searchAll)
 * @param x an object
 * @param ft test function (v, k, x)
 * @returns [k₀, k₁, ...] | ft(x[kᵢ]) passes
 */
declare function searchAll(x: object, ft: TestFunction): string[];
/**
 * Find key with a given value.
 * [📘](https://github.com/nodef/extra-object/wiki/searchValue)
 * @param x an object
 * @param v search value
 * @param fc compare function (a, b)
 * @param fm map function (v, k, x)
 * @returns k | fm(x[k]) ≈ fm(v)
 */
declare function searchValue(x: object, v: any, fc?: CompareFunction | null, fm?: MapFunction | null): string;
/**
 * Find keys with a given value.
 * [📘](https://github.com/nodef/extra-object/wiki/searchValueAll)
 * @param x an object
 * @param v search value
 * @param fc compare function (a, b)
 * @param fm map function (v, k, x)
 * @returns [k₀, k₁, ...] | fm(x[kᵢ]) ≈ fm(v)
 */
declare function searchValueAll(x: object, v: any, fc?: CompareFunction | null, fm?: MapFunction | null): string[];
/**
 * Call a function for each entry.
 * [📘](https://github.com/nodef/extra-object/wiki/forEach)
 * @param x an object
 * @param fp called function (v, k, x)
 */
declare function forEach(x: object, fp: ProcessFunction): void;
/**
 * Check if any value satisfies a test.
 * [📘](https://github.com/nodef/extra-object/wiki/some)
 * @param x an object
 * @param ft test function (v, k, x)
 * @returns true if ft(vᵢ) = true for some [kᵢ, vᵢ] ∈ x
 */
declare function some(x: object, ft?: TestFunction | null): boolean;
/**
 * Check if all values satisfy a test.
 * [📘](https://github.com/nodef/extra-object/wiki/every)
 * @param x an object
 * @param ft test function (v, k, x)
 * @returns true if ft(vᵢ) = true for all [kᵢ, vᵢ] ∈ x
 */
declare function every(x: object, ft: TestFunction): boolean;
/**
 * Transform values of an object.
 * [📘](https://github.com/nodef/extra-object/wiki/map)
 * @param x an object
 * @param fm map function (v, k, x)
 * @returns \{[k₀, fm(v₀)], [k₁, fm(v₁)], ...\} | [kᵢ, vᵢ] ∈ x
 */
declare function map(x: object, fm: MapFunction): object;
/**
 * Transform values of an object.
 * [📘](https://github.com/nodef/extra-object/wiki/map$)
 * @param x an object (updated)
 * @param fm map function (v, k, x)
 * @returns x = \{[k₀, fm(v₀)], [k₁, fm(v₁)], ...\} | [kᵢ, vᵢ] ∈ x
 */
declare function map$(x: object, fm: MapFunction): object;
/**
 * Reduce values to a single value.
 * [📘](https://github.com/nodef/extra-object/wiki/reduce)
 * @param x an object
 * @param fr reduce function (acc, v, k, x)
 * @param acc initial value
 * @returns fr(fr(acc, v₀), v₁)... | fr(acc, v₀) = v₀ if acc not given
 */
declare function reduce(x: object, fr: ReduceFunction, acc?: any): any;
/**
 * Keep entries which pass a test.
 * [📘](https://github.com/nodef/extra-object/wiki/filter)
 * @param x an object
 * @param ft test function (v, k, x)
 * @returns \{[k₀, v₀], [k₁, v₁], ...\} | ft(vᵢ) = true; [kᵢ, vᵢ] ∈ x
 */
declare function filter(x: object, ft: TestFunction): object;
/**
 * Keep entries which pass a test.
 * [📘](https://github.com/nodef/extra-object/wiki/filter$)
 * @param x an object (updated)
 * @param ft test function (v, k, x)
 * @returns x = \{[k₀, v₀], [k₁, v₁], ...\} | ft(vᵢ) = true; [kᵢ, vᵢ] ∈ x
 */
declare function filter$(x: object, ft: TestFunction): object;
/**
 * Get object with given keys.
 * [📘](https://github.com/nodef/extra-object/wiki/filterAt)
 * @param x an object
 * @param ks keys
 * @returns \{[k₀, v₀], [k₁, v₁], ...\} | kᵢ ∈ ks; [kᵢ, vᵢ] ∈ x
 */
declare function filterAt(x: object, ks: string[]): object;
/**
 * Get object with given keys.
 * [📘](https://github.com/nodef/extra-object/wiki/filterAt$)
 * @param x an object (updated)
 * @param ks keys
 * @returns x = \{[k₀, v₀], [k₁, v₁], ...\} | kᵢ ∈ ks; [kᵢ, vᵢ] ∈ x
 */
declare function filterAt$(x: object, ks: string[]): object;
/**
 * Discard entries which pass a test.
 * [📘](https://github.com/nodef/extra-object/wiki/reject)
 * @param x an object
 * @param ft test function (v, k, x)
 * @returns \{[k₀, v₀], [k₁, v₁], ...\} | ft(vᵢ) = false; [kᵢ, vᵢ] ∈ x
 */
declare function reject(x: object, ft: TestFunction): object;
/**
 * Discard entries which pass a test.
 * [📘](https://github.com/nodef/extra-object/wiki/reject$)
 * @param x an object (updated)
 * @param ft test function (v, k, x)
 * @returns x = \{[k₀, v₀], [k₁, v₁], ...\} | ft(vᵢ) = false; [kᵢ, vᵢ] ∈ x
 */
declare function reject$(x: object, ft: TestFunction): object;
/**
 * Get object without given keys.
 * [📘](https://github.com/nodef/extra-object/wiki/rejectAt)
 * @param x an object
 * @param ks keys
 * @returns \{[k₀, v₀], [k₁, v₁], ...\} | kᵢ ∉ ks; [kᵢ, vᵢ] ∈ x
 */
declare function rejectAt(x: object, ks: string[]): object;
/**
 * Get object without given keys.
 * [📘](https://github.com/nodef/extra-object/wiki/rejectAt$)
 * @param x an object (updated)
 * @param ks keys
 * @returns x = \{[k₀, v₀], [k₁, v₁], ...\} | kᵢ ∉ ks; [kᵢ, vᵢ] ∈ x
 */
declare function rejectAt$(x: object, ks: string[]): object;
/**
 * Flatten nested object to given depth.
 * [📘](https://github.com/nodef/extra-object/wiki/flat)
 * @param x a nested object
 * @param n maximum depth [-1 ⇒ all]
 * @param fm map function (v, k, x)
 * @param ft test function for flatten (v, k, x)
 * @returns flat map
 */
declare function flat(x: object, n?: number, fm?: MapFunction | null, ft?: TestFunction | null): object;
/**
 * Flatten nested object, using map function.
 * [📘](https://github.com/nodef/extra-object/wiki/flatMap)
 * @param x a nested object
 * @param fm map function (v, k, x)
 * @param ft test function (v, k, x)
 * @returns flat map
 */
declare function flatMap(x: object, fm?: MapFunction | null, ft?: TestFunction | null): object;
/**
 * Combine matching entries from objects.
 * [📘](https://github.com/nodef/extra-object/wiki/zip)
 * @param xs objects
 * @param fm map function (vs, k)
 * @param fe end function (dones) [array.some]
 * @param vd default value
 * @returns \{"k₀": fm([x₀[k₀], x₁[k₀], ...]), "k₁": fm([x₀[k₁], x₁[k₁], ...]), ...\}
 */
declare function zip(xs: object[], fm?: MapFunction | null, fe?: EndFunction | null, vd?: any): object;
/**
 * Segregate entries by test result.
 * [📘](https://github.com/nodef/extra-object/wiki/partition)
 * @param x an object
 * @param ft test function (v, k, x)
 * @returns [satisfies, doesnt]
 */
declare function partition(x: object, ft: TestFunction): [object, object];
/**
 * Segregate entries by similarity.
 * [📘](https://github.com/nodef/extra-object/wiki/partitionAs)
 * @param x an object
 * @param fm map function (v, k, x)
 * @returns Map \{key ⇒ values\}
 */
declare function partitionAs(x: object, fm: MapFunction): Map<any, object>;
/**
 * Break object into chunks of given size.
 * [📘](https://github.com/nodef/extra-object/wiki/chunk)
 * @param x an object
 * @param n chunk size [1]
 * @param s chunk step [n]
 * @returns [x[0..n], x[s..s+n], x[2s..2s+n], ...]
 */
declare function chunk(x: object, n?: number, s?: number): object[];
/**
 * Combine entries from objects, preferring last.
 * [📘](https://github.com/nodef/extra-object/wiki/concat)
 * @param xs objects
 * @returns x₀ ∪ x₁ ∪ ... | [x₀, x₁, ...] = xs
 */
declare function concat(...xs: object[]): object;
/**
 * Combines entries from objects, preferring last.
 * [📘](https://github.com/nodef/extra-object/wiki/concat$)
 * @param x an object (updated)
 * @param ys other objects
 * @returns x = x ∪ y₀ ∪ y₁ ∪ ... | [y₀, y₁, ...] = ys
 */
declare function concat$(x: object, ...ys: object[]): object;
/**
 * Join entries together into a string.
 * [📘](https://github.com/nodef/extra-object/wiki/join)
 * @param x an object
 * @param sep separator [,]
 * @param asc associator [=]
 * @returns "k₀=v₀,k₁=v₁,..." | [kᵢ, vᵢ] ∈ x
 */
declare function join(x: object, sep?: string, asc?: string): string;
/**
 * Check if objects have no common keys.
 * [📘](https://github.com/nodef/extra-object/wiki/isDisjoint)
 * @param x an object
 * @param y another object
 * @returns x ∩ y = Φ?
 */
declare function isDisjoint(x: object, y: object): boolean;
/**
 * Obtain keys present in any object.
 * [📘](https://github.com/nodef/extra-object/wiki/unionKeys)
 * @param xs objects
 * @returns [k₀, k₁, ...] | [kᵢ, vᵢ] ∈ x₀ ∪ x₁, ...; [x₀, x₁, ...] = xs
 */
declare function unionKeys(...xs: object[]): Set<string>;
/**
 * Obtain entries present in any object.
 * [📘](https://github.com/nodef/extra-object/wiki/union)
 * @param x an object
 * @param y another object
 * @param fc combine function (a, b)
 * @returns x ∪ y = \{[kᵢ, vᵢ] | [kᵢ, vᵢ] ∈ x or [kᵢ, vᵢ] ∈ y\}
 */
declare function union(x: object, y: object, fc?: CombineFunction | null): object;
/**
 * Obtain entries present in any object.
 * [📘](https://github.com/nodef/extra-object/wiki/union$)
 * @param x an object (updated)
 * @param y another object
 * @param fc combine function (a, b)
 * @returns x = x ∪ y = \{[kᵢ, vᵢ] | [kᵢ, vᵢ] ∈ x or [kᵢ, vᵢ] ∈ y\}
 */
declare function union$(x: object, y: object, fc?: CombineFunction | null): object;
/**
 * Obtain keys present in all objects.
 * [📘](https://github.com/nodef/extra-object/wiki/intersectionKeys)
 * @param xs objects
 * @returns [k₀, k₁, ...] | [kᵢ, vᵢ] ∈ x₀ ∩ x₁, ...; [x₀, x₁, ...] = xs
 */
declare function intersectionKeys(...xs: object[]): Set<string>;
/**
 * Obtain entries present in both objects.
 * [📘](https://github.com/nodef/extra-object/wiki/intersection)
 * @param x an object
 * @param y another object
 * @param fc combine function (a, b)
 * @returns x ∩ y = \{[kᵢ, vᵢ] | [kᵢ, vᵢ] ∈ x and [kᵢ, vᵢ] ∈ y\}
 */
declare function intersection(x: object, y: object, fc?: CombineFunction | null): object;
/**
 * Obtain entries present in both objects.
 * [📘](https://github.com/nodef/extra-object/wiki/intersection$)
 * @param x an object (updated)
 * @param y another object
 * @param fc combine function (a, b)
 * @returns x = x ∩ y = \{[kᵢ, vᵢ] | [kᵢ, vᵢ] ∈ x and [kᵢ, vᵢ] ∈ y\}
 */
declare function intersection$(x: object, y: object, fc?: CombineFunction | null): object;
/**
 * Obtain entries not present in another object.
 * [📘](https://github.com/nodef/extra-object/wiki/difference)
 * @param x an object
 * @param y another object
 * @returns x - y = \{[kᵢ, vᵢ] | [kᵢ, vᵢ] ∈ x, [kᵢ, *] ∉ y\}
 */
declare function difference(x: object, y: object): object;
/**
 * Obtain entries not present in another object.
 * [📘](https://github.com/nodef/extra-object/wiki/difference$)
 * @param x an object (updated)
 * @param y another object
 * @returns x = x - y = \{[kᵢ, vᵢ] | [kᵢ, vᵢ] ∈ x, [kᵢ, *] ∉ y\}
 */
declare function difference$(x: object, y: object): object;
/**
 * Obtain entries not present in both objects.
 * [📘](https://github.com/nodef/extra-object/wiki/symmetricDifference)
 * @param x an object
 * @param y another object
 * @returns x-y ∪ y-x
 */
declare function symmetricDifference(x: object, y: object): object;
/**
 * Obtain entries not present in both objects.
 * [📘](https://github.com/nodef/extra-object/wiki/symmetricDifference$)
 * @param x an object (updated)
 * @param y another object
 * @returns x = x-y ∪ y-x
 */
declare function symmetricDifference$(x: object, y: object): object;
/**
 * List cartesian product of objects.
 * [📘](https://github.com/nodef/extra-object/wiki/cartesianProduct)
 * @param xs objects
 * @param fm map function (vs)
 * @returns x₀ × x₁ × ... = \{\{[k₀, v₀], [k₁, v₁], ...\} | [k₀, v₀] ∈ x₀, [k₁, v₁] ∈ x₁, ...]\}
 */
declare function cartesianProduct(xs: object[], fm?: MapFunction | null): IterableIterator<any>;

export { CombineFunction, CompareFunction, EndFunction, Entries, Lists, MapFunction, ProcessFunction, ReadFunction, ReduceFunction, TestFunction, cartesianProduct, chunk, compare, concat, concat$, count, countAs, difference, difference$, drop, drop$, entries, randomEntry as entry, every, filter, filter$, filterAt, filterAt$, find, findAll, flat, flatMap, forEach, fromEntries, fromLists, get, getAll, getPath, has, hasEntry, has as hasKey, hasPath, hasSubset, hasValue, head, intersection, intersection$, intersectionKeys, is, isDisjoint, isEmpty, isEqual, join, randomKey as key, keys, size as length, map, map$, max, maxEntry, min, minEntry, partition, partitionAs, randomEntry, randomKey, randomSubset, range, rangeEntries, reduce, reject, reject$, rejectAt, rejectAt$, remove, remove$, removePath$, search, searchAll, searchValue, searchValueAll, set, set$, setPath$, size, some, randomSubset as subset, subsets, swap, swap$, symmetricDifference, symmetricDifference$, tail, take, take$, union, union$, unionKeys, values, zip };