@mobily/ts-belt/dist/types/Dict/index.js.flow

🔧 Fast, modern, and practical utility library for FP in TypeScript.

// @flow

import type { Option } from "../Option";
import type { ExtractValue } from "../types";
import type { Array } from "../types";

/**
 * Creates an empty object. Alternative for `const obj = {} as SomeObjectType`.
 */
declare export function makeEmpty<T>(): T;

/**
 * Returns the value if the given key exists, otherwise returns `undefined`.
 */
declare export function getUnsafe<T, K: $Keys<T>>(
  dict: T,
  key: K
): $ElementType<T, K>;
declare export function getUnsafe<T, K: $Keys<T>>(
  key: K
): (dict: T) => $ElementType<T, K>;

/**
 * Returns `Some(value)` if the given key exists, otherwise returns `None`.
 */
declare export function get<T, K: $Keys<T>>(
  dict: T,
  key: K
): Option<ExtractValue<$ElementType<T, K>>>;
declare export function get<T, K: $Keys<T>>(
  key: K
): (dict: T) => Option<ExtractValue<$ElementType<T, K>>>;

/**
 * @deprecated Use either `D.get` or `D.getUnsafe` instead.
 */
declare export function prop<T, K: $Keys<T>>(
  dict: T,
  key: K
): $ElementType<T, K>;
declare export function prop<T, K: $Keys<T>>(
  key: K
): (dict: T) => $ElementType<T, K>;

/**
 * Converts an object into an array of `[key, value]` tuples.
 */
declare export function toPairs<T, K: string | number>(dict: {
  [key: K]: T,
  ...
}): Array<[string, T]>;

/**
 * Returns a new array that contains all values of the provided object.
 */
declare export function values<T: string | number, R>(dict: {
  [key: T]: R,
  ...
}): Array<R>;

/**
 * Returns a new array that contains all keys of the provided object.
 */
declare export function keys<T: { [key: string]: mixed, ... }>(
  dict: T
): Array<$Keys<T>>;

/**
 * Creates a new object from an array of tuples (`[key, value]`).
 */
declare export function fromPairs<T, K: string | number>(
  xs: Array<[K, T]>
): { [key: string]: T, ... };

/**
 * Merges two provided objects.
 */
declare export function merge<A, B>(fst: A, snd: B): { ...A, ...B };
declare export function merge<A, B>(snd: B): (fst: A) => { ...A, ...B };

/**
 * Adds a property. Equivalent to merging with `{key: value}`
 */
declare export function set<T, K: string | number, V>(
  dict: T,
  key: K,
  value: V
): { ...T, ...{ [key: K]: V, ... } };
declare export function set<T, K: string | number, V>(
  key: K,
  value: V
): (dict: T) => { ...T, ...{ [key: K]: V, ... } };

/**
 * Updates a property by applying the provided function to the corresponding optional value.
 */
declare export function update<T, K: $Keys<T>, R>(
  dict: T,
  key: K,
  fn: (value: Option<$ElementType<T, K>>) => R
): { ...T, ...{ [key: K]: R, ... } };
declare export function update<T, K: $Keys<T>, R>(
  key: K,
  fn: (value: Option<$ElementType<T, K>>) => R
): (dict: T) => { ...T, ...{ [key: K]: R, ... } };

/**
 * Updates a property by applying the provided function to the corresponding value.
 */
declare export function updateUnsafe<T, K: $Keys<T>, R>(
  dict: T,
  key: K,
  fn: (value: $ElementType<T, K>) => R
): { ...T, ...{ [key: K]: R, ... } };
declare export function updateUnsafe<T, K: $Keys<T>, R>(
  key: K,
  fn: (value: $ElementType<T, K>) => R
): (dict: T) => { ...T, ...{ [key: K]: R, ... } };

/**
 * Returns a new object with the provided key deleted.
 */
declare export function deleteKey<T, K: $Keys<T>>(
  dict: T,
  key: K
): $Diff<T, { [key: K]: any }>;
declare export function deleteKey<T, K: $Keys<T>>(
  key: K
): (dict: T) => $Diff<T, { [key: K]: any }>;

/**
 * Returns a new object with the provided keys deleted.
 */
declare export function deleteKeys<T, K: $Keys<T>>(
  dict: T,
  keys: $ReadOnlyArray<K>
): $Diff<T, { [key: K]: any }>;
declare export function deleteKeys<T, K: $Keys<T>>(
  keys: $ReadOnlyArray<K>
): (dict: T) => $Diff<T, { [key: K]: any }>;

/**
 * Transforms each value in the object to a new value using the provided function.
 */
declare export function map<T: { [key: string]: any, ... }, R>(
  dict: T,
  mapFn: (value: $ElementType<T, $Keys<T>>) => R
): { [key: $Keys<T>]: R, ... };
declare export function map<T: { [key: string]: any, ... }, R>(
  mapFn: (value: $ElementType<T, $Keys<T>>) => R
): (dict: T) => { [key: $Keys<T>]: R, ... };

/**
 * Transforms each value in the object to a new value using the provided function (which takes two arguments: a property value and key).
 */
declare export function mapWithKey<T: { [key: string]: any, ... }, R>(
  dict: T,
  mapFn: (key: $Keys<T>, value: $ElementType<T, $Keys<T>>) => R
): { [key: $Keys<T>]: R, ... };
declare export function mapWithKey<T: { [key: string]: any, ... }, R>(
  mapFn: (key: $Keys<T>, value: $ElementType<T, $Keys<T>>) => R
): (dict: T) => { [key: $Keys<T>]: R, ... };

/**
 * Removes each property that doesn't satisfy the given predicate function.
 */
declare export function filter<T: { [key: string]: any, ... }>(
  dict: T,
  predicateFn: (value: $ElementType<T, $Keys<T>>) => boolean
): $Rest<T, { ... }>;
declare export function filter<T: { [key: string]: any, ... }>(
  predicateFn: (value: $ElementType<T, $Keys<T>>) => boolean
): (dict: T) => $Rest<T, { ... }>;

/**
 * Removes each property that doesn't satisfy the given predicate function (which takes two arguments: a property value and key).
 */
declare export function filterWithKey<T: { [key: string]: any, ... }>(
  dict: T,
  predicateFn: (key: $Keys<T>, value: $ElementType<T, $Keys<T>>) => boolean
): $Rest<T, { ... }>;
declare export function filterWithKey<T: { [key: string]: any, ... }>(
  predicateFn: (key: $Keys<T>, value: $ElementType<T, $Keys<T>>) => boolean
): (dict: T) => $Rest<T, { ... }>;

/**
 * Removes each property that satisfies the given predicate function.
 */
declare export function reject<T: { [key: string]: any, ... }>(
  dict: T,
  predicateFn: (value: $ElementType<T, $Keys<T>>) => boolean
): $Rest<T, { ... }>;
declare export function reject<T: { [key: string]: any, ... }>(
  predicateFn: (value: $ElementType<T, $Keys<T>>) => boolean
): (dict: T) => $Rest<T, { ... }>;

/**
 * Removes each property that satisfies the given predicate function (which takes two arguments: a property value and key).
 */
declare export function rejectWithKey<T: { [key: string]: any, ... }>(
  dict: T,
  predicateFn: (key: $Keys<T>, value: $ElementType<T, $Keys<T>>) => boolean
): $Rest<T, { ... }>;
declare export function rejectWithKey<T: { [key: string]: any, ... }>(
  predicateFn: (key: $Keys<T>, value: $ElementType<T, $Keys<T>>) => boolean
): (dict: T) => $Rest<T, { ... }>;

/**
 * Returns a new object with the provided keys selected.
 */
declare export function selectKeys<T, K: $Keys<T>>(
  dict: T,
  keys: $ReadOnlyArray<K>
): Pick<T, K>;
declare export function selectKeys<T, K: $Keys<T>>(
  keys: $ReadOnlyArray<K>
): (dict: T) => Pick<T, K>;

/**
 * Determines whether the given object is empty.
 */
declare export function isEmpty<T: { [key: string]: any, ... }>(
  dict: T
): boolean;

/**
 * Determines whether the given object is not empty.
 */
declare export function isNotEmpty<T: { [key: string]: any, ... }>(
  dict: T
): boolean;