@codibre/fluent-iterable/dist/types/function-types/to-map-chain-function.d.ts

Provides LINQ-like fluent api operations for iterables and async iterables (ES2018+).

import { Mapper } from 'augmentative-iterable';
import { AsyncReducer, ItemType, Reducer } from '../base';
import { BaseChainKeyType, Indexes } from './to-object-chain-function';
export type ToMapChainKey<T> = keyof T | Mapper<T, unknown>;
export type ToMapChainValueOf<V, K extends ToMapChainKey<V>> = K extends Mapper<V, unknown> ? ReturnType<K> : K extends keyof V ? V[K] : never;
export type MapChain<Arr extends Array<ToMapChainKey<V>>, V, R = V[], Pos extends number = 0> = {
    done: R;
    any: any;
    recur: ToMapChainValueOf<V, Arr[Pos]> extends BaseChainKeyType ? Map<ToMapChainValueOf<V, Arr[Pos]>, MapChain<Arr, V, R, Indexes[Pos]>> : ToMapChainValueOf<V, Arr[Pos]> extends Iterable<unknown> ? Map<ItemType<ToMapChainValueOf<V, Arr[Pos]>>, MapChain<Arr, V, R, Indexes[Pos]>> : never;
}[Pos extends Arr['length'] ? 'done' : Pos extends -1 ? 'any' : 'recur'];
export interface ToMapChainFunction<T> {
    /**
     * Creates an map chain with the values of the specified fields where the latest
     * value in the chain will be the iterable item itself. This is a resolving operation
     * @param keys The keys to be chained
     * @returns The object chain
     */
    <A extends Array<ToMapChainKey<T>>>(...keys: A): MapChain<A, T>;
}
export interface AsyncToMapChainFunction<T> {
    /**
     * Creates an map chain with the values of the specified fields where the latest
     * value in the chain will be the iterable item itself. This is a resolving operation
     * @param keys The keys to be chained. It can be either property names or mapping functions
     * @returns The object chain
     */
    <A extends Array<ToMapChainKey<T>>>(...keys: A): Promise<MapChain<A, T>>;
}
export interface ToMapChainReduceFunction<T> {
    /**
     * Creates an map chain with the values of the specified fields where the latest
     * value in the chain will be the iterable item itself. This is a resolving operation
     * @param initial An initializer function to define the base value for each leaf
     * @param reduce: A reduce function to accumulate the leaf value for each value that fits it
     * @param keys The keys to be chained. It can be either property names or mapping functions
     * @returns The object chain
     */
    <A extends Array<ToMapChainKey<T>>, R>(initial: () => R, reduce: Reducer<T, R>, ...keys: A): MapChain<A, T, R>;
}
export interface AsyncToMapChainReduceFunction<T> {
    /**
     * Creates an map chain with the values of the specified fields where the latest
     * value in the chain will be the iterable item itself. This is a resolving operation
     * @param initial An initializer function to define the base value for each leaf
     * @param reduce: A reduce function to accumulate the leaf value for each value that fits it
     * @param keys The keys to be chained. It can be either property names or mapping functions
     * @returns The object chain
     */
    <A extends Array<ToMapChainKey<T>>, R>(initial: () => R, reduce: AsyncReducer<T, R>, ...keys: A): Promise<MapChain<A, T, R>>;
}