ramda.d.ts

// Type definitions for ramda
// Based on code from https://github.com/donnut/typescript-ramda
// Moved to typings format by Rich Adams <https://github.com/enriched>

declare var R: R.Static;

declare module R {

    /**
     * A special placeholder value used to specify "gaps" within curried functions,
     * allowing partial application of any combination of arguments, regardless of their positions.
     */
    interface placeholder {}

    interface ListIterator<T, TResult> {
        (value: T, index: number, list: T[]): TResult;
    }

    interface ObjectIterator<T, TResult> {
        (element: T, key: string, obj: Dictionary<T>): Dictionary<TResult>;
    }
    interface KeyValuePair<K, V> extends Array<K | V> { 0 : K; 1 : V; }

    interface ArrayLike {
        nodeType: number;
    }

    interface Arity0Fn {
        (): any;
    }

    interface Arity1Fn {
        (a: any): any;
    }

    interface Arity2Fn {
        (a: any, b: any): any;
    }

    interface ObjFunc {
        [index:string]: Function;
    }

    interface ObjFunc2 {
        [index:string]: (x: any, y: any) => boolean;
    }

    interface Pred {
        (...a: any[]): boolean;
    }

    interface ObjPred {
        (value: any, key: string): boolean;
    }

    interface Dictionary<T> {
        [index: string]: T;
    }

    interface CharList extends String {
        push(x: string): void;
    }

    interface Lens {
        <T,U>(obj: T): U;
        set<T,U>(str: string, obj: T): U;
    }


    // @see https://gist.github.com/donnut/fd56232da58d25ceecf1, comment by @albrow
    interface CurriedFunction2<T1, T2, R> {
        (t1: T1): (t2: T2) => R;
        (t1: T1, t2: T2): R;
    }

    interface CurriedFunction3<T1, T2, T3, R> {
        (t1: T1): CurriedFunction2<T2, T3, R>;
        (t1: T1, t2: T2): (t3: T3) => R;
        (t1: T1, t2: T2, t3: T3): R;
    }

    interface CurriedFunction4<T1, T2, T3, T4, R> {
        (t1: T1): CurriedFunction3<T2, T3, T4, R>;
        (t1: T1, t2: T2): CurriedFunction2<T3, T4, R>;
        (t1: T1, t2: T2, t3: T3): (t4: T4) => R;
        (t1: T1, t2: T2, t3: T3, t4: T4): R;
    }

    interface CurriedFunction5<T1, T2, T3, T4, T5, R> {
        (t1: T1): CurriedFunction4<T2, T3, T4, T5, R>;
        (t1: T1, t2: T2): CurriedFunction3<T3, T4, T5, R>;
        (t1: T1, t2: T2, t3: T3): CurriedFunction2<T4, T5, R>;
        (t1: T1, t2: T2, t3: T3, t4: T4): (t5: T5) => R;
        (t1: T1, t2: T2, t3: T3, t4: T4, t5: T5): R;
    }

    interface CurriedFunction6<T1, T2, T3, T4, T5, T6, R> {
        (t1: T1): CurriedFunction5<T2, T3, T4, T5, T6, R>;
        (t1: T1, t2: T2): CurriedFunction4<T3, T4, T5, T6, R>;
        (t1: T1, t2: T2, t3: T3): CurriedFunction3<T4, T5, T6, R>;
        (t1: T1, t2: T2, t3: T3, t4: T4): CurriedFunction2<T5, T6, R>;
        (t1: T1, t2: T2, t3: T3, t4: T4, t5: T5): (t6: T6) => R;
        (t1: T1, t2: T2, t3: T3, t4: T4, t5: T5, t6: T6): R;
    }

    type AnyCurriedFunction = CurriedFunction2<any,any,any> | CurriedFunction3<any,any,any,any> | CurriedFunction4<any,any,any,any,any> | CurriedFunction5<any,any,any,any,any,any> | CurriedFunction6<any,any,any,any,any,any,any>;

    interface Static {
        /*
         * List category
         */


        /**
         * Applies a function to the value at the given index of an array, returning a new copy of the array with the element at the given index replaced with the result of the function application.
         */
        adjust<T>(fn: (a: T) => T, index: number, list: T[]): T[];
        adjust<T>(fn: (a: T) => T, index: number): (list: T[]) => T[];

        /**
         * Returns true if all elements of the list match the predicate, false if there are any that don't.
         */
        all<T>(fn: (a: T) => boolean, list: T[]): boolean;
        all<T>(fn: (a: T) => boolean): (list: T[]) => boolean;

        /**
         * Returns true if at least one of elements of the list match the predicate, false otherwise.
         */
        any<T>(fn: (a: T) => boolean, list: T[]): boolean;
        any<T>(fn: (a: T) => boolean): (list: T[]) => boolean;

        /**
         * Returns a new list, composed of n-tuples of consecutive elements If n is greater than the length of the list, an empty list is returned.
         */
        aperture<T>(n: number, list: T): T[][];
        aperture<T>(n: number): (list: T) => T[][];

        /**
         * Returns a new list containing the contents of the given list, followed by the given element.
         */
        // note U is required (instead of just T) to allow appending an element of a different type than the array is.
        append<T>(el: T, list: T[]): T[];
        append<T>(el: T): (list: T[]) => T[];
        append<T, U>(el: U, list: T[]): (T & U)[];
        append<T, U>(el: U): (list: T[]) => (T & U)[];

        /**
         * `chain` maps a function over a list and concatenates the results.
         * This implementation is compatible with the Fantasy-land Chain spec
         */
        chain<T, U>(fn: (n: T) => U[], list: T[]): U[];
        chain<T, U>(fn: (n: T) => U[]): (list: T[]) => U[];

        /**
         * Turns a list of Functors into a Functor of a list.
         */
        commute<T, U>(of: (x: T) => U, list: U[]): U;
        commute<T, U>(of: (x: T) => U): (list: U[]) => U;
        commute<T, U>(of: (x: T) => T[], list: U[]): U[]
        commute<T, U>(of: (x: T) => T[]): (list: U[]) => U[]
        /*
         * Turns a list of Functors into a Functor of a list, applying a mapping function to the elements of the list along the way.
         */
        commuteMap<T, U>(fn: (list: T[]) => U[], of: (x: T[]) => U[][], list: T[][]): U[][];
        commuteMap<T, U>(fn: (list: T[]) => U[]): (of: (x: T[]) => U[][], list: T[][]) => U[][];
        commuteMap<T, U>(fn: (list: T[]) => U[], of: (x: T[]) => U[][]): (list: T[][]) => U[][];

        /**
         * Returns a new list consisting of the elements of the first list followed by the elements
         * of the second.
         */
        concat<T>(list1: T[], list2: T[]): T[];
        concat<T>(list1: T[]): (list2: T[]) => T[];
        concat<T>(list1: string, list2: string): string;
        concat<T>(list1: string): (list2: string) => string;

        /**
         * Returns `true` if the specified item is somewhere in the list, `false` otherwise.
         * Equivalent to `indexOf(a)(list) > -1`. Uses strict (`===`) equality checking.
         */
        contains(a: string, list: string): boolean;
        contains<T>(a: T, list: T[]): boolean;
        contains(a: string): (list: string) => boolean;
        contains<T>(a: T): (list: T[]) => boolean;

        /**
         * Returns `true` if the `x` is found in the `list`, using `pred` as an
         * equality predicate for `x`.
         */
        containsWith<T>(pred: (a: T, b: T) => boolean, x: T, list: T[]): boolean;
        containsWith<T>(pred: (a: T, b: T) => boolean, x: T): (list: T[]) => boolean;

        /**
         * Returns a new list containing all but the first n elements of the given list.
         */
        drop<T>(n: number, list: T[]): T[];
        drop<T>(n: number): (list: T[]) => T[];

        dropLast<T>(n: number, list: T[]): T[];
        dropLast<T>(n: number): (list: T[]) => T[];

        dropLastWhile<T>(fn: (a: T) => boolean, list: T[]): T[];
        dropLastWhile<T>(fn: (a: T) => boolean): (list: T[]) => T[];

        dropRepeats<T>(list: T[]): T[];

        dropRepeatsWith<T>(fn: (l: T, r: T) => boolean, list: T[]): T[];
        dropRepeatsWith<T>(fn: (l: T, r: T) => boolean): (list: T[]) => T[];

        /**
         * Returns a new list containing the last n elements of a given list, passing each value to the supplied
         * predicate function, skipping elements while the predicate function returns true.
         */
        dropWhile<T>(fn: (a: T) => boolean, list: T[]): T[];
        dropWhile<T>(fn: (a: T) => boolean): (list: T[]) => T[];

        /**
         * Returns a new list containing only those items that match a given predicate function. The predicate function is passed one argument: (value).
         */
        filter<T>(fn: (value: T) => boolean): (list: T[]) => T[];
        filter<T>(fn: (value: T) => boolean, list: T[]): T[];

        /**
         * Like filter, but passes additional parameters to the predicate function. The predicate function is passed three arguments: (value, index, list).
         */
        filterIndexed<T>(fn: (value: T, index: number, list: T[]) => boolean): (list: T[]) => T[];
        filterIndexed<T>(fn: (value: T, index: number, list: T[]) => boolean, list: T[]): T[];

        /**
         * Returns the first element of the list which matches the predicate, or `undefined` if no
         * element matches.
         */
        find<T>(fn: (a: T) => boolean, list: T[]): T;
        find<T>(fn: (a: T) => boolean): (list: T[]) => T;


        /**
         * Returns the index of the first element of the list which matches the predicate, or `-1`
         * if no element matches.
         */
        findIndex<T>(fn: (a: T) => boolean, list: T[]): number;
        findIndex<T>(fn: (a: T) => boolean): (list: T[]) => number;

        /**
         * Returns the last element of the list which matches the predicate, or `undefined` if no
         * element matches.
         */
        findLast<T>(fn: (a: T) => boolean, list: T[]): T;
        findLast<T>(fn: (a: T) => boolean): (list: T[]) => T;

        /**
         * Returns the index of the last element of the list which matches the predicate, or
         * `-1` if no element matches.
         */
        findLastIndex<T>(fn: (a: T) => boolean, list: T[]): number;
        findLastIndex<T>(fn: (a: T) => boolean): (list: T[]) => number;

        /**
         * Returns a new list by pulling every item out of it (and all its sub-arrays) and putting
         * them in a new array, depth-first.
         */
        flatten<T>(x: T[]): T[];

        /**
         * Iterate over an input list, calling a provided function fn for each element in the list.
         */
        forEach<T>(fn: (x: T) => void, list: T[]): T[];
        forEach<T>(fn: (x: T) => void): (list: T[]) => T[];

        /**
         * Like forEach, but but passes additional parameters to the predicate function.
         */
        forEachIndexed<T>(fn: (x: T, idx?: number, list?: T[]) => void, list: T[]): T[];
        forEachIndexed<T>(fn: (x: T, idx?: number, list?: T[]) => void): (list: T[]) => T[];

        /**
         * Creates a new object out of a list key-value pairs.
         */
        fromPairs<V>(pairs: KeyValuePair<string, V>[]): {[index: string]: V};
        fromPairs<V>(pairs: KeyValuePair<number, V>[]): {[index: number]: V};


        /**
         * Splits a list into sublists stored in an object, based on the result of
         * calling a String-returning function
         * on each element, and grouping the results according to values returned.
         */
        groupBy<T>(fn: (a: T) => string, list: T[]): {[index: string]: T[]}
        groupBy<T>(fn: (a: T) => string): <T>(list: T[]) => {[index: string]: T[]}

        /**
         * Returns the first element in a list.
         * In some libraries this function is named `first`.
         */
        head<T>(list: T[]): T;

        /**
         * Returns the position of the first occurrence of an item in an array
         * (by strict equality),
         * or -1 if the item is not included in the array.
         */
        indexOf<T>(target: T, list: T[]): number;
        indexOf<T>(target: T): (list: T[]) => number;

        /**
         * Returns all but the last element of a list.
         */
        init<T>(list: T[]): T[];

        /**
         * Inserts the supplied element into the list, at index index. Note that
         * this is not destructive: it returns a copy of the list with the changes.
         */
        insert(index: number, elt: any, list: any[]): any[];
        insert(index: number): (elt: any, list: any[]) => any[];
        insert(index: number, elt: any): (list: any[]) => any[];

        /**
         * Inserts the sub-list into the list, at index `index`.  _Note  that this
         * is not destructive_: it returns a copy of the list with the changes.
         */
        insertAll(index: number, elts: any[], list: any[]): any[];
        insertAll(index: number): (elts: any[], list: any[]) => any[];
        insertAll(index: number, elts: any[]): (list: any[]) => any[];

        /**
         * Transforms the items of the list with the transducer and appends the transformed items to the accumulator
         * using an appropriate iterator function based on the accumulator type.
         */
        into<T>(acc: any, xf: Function, list: T[]): T[];
        into<T>(acc: any, xf: Function): (list: T[]) => T[];
        into<T>(acc: any): (xf: Function, list: T[]) => T[];


        /**
         * Returns `true` if all elements are unique, otherwise `false`.
         * Uniqueness is determined using strict equality (`===`).
         */
        isSet(list: any[]): boolean;

        /**
         * Returns a string made by inserting the `separator` between each
         * element and concatenating all the elements into a single string.
         */
        join(x: string, xs: any[]): string;
        join(x: string): (xs: any[]) => string;

        /**
         * Returns the last element from a list.
         */
        last<T>(list: T[]): T;

        /**
         * Returns the position of the last occurrence of an item (by strict equality) in
         * an array, or -1 if the item is not included in the array.
         */
        lastIndexOf<T>(target: T, list: T[]): number;

        /**
         * Returns the number of elements in the array by returning list.length.
         */
        length(list: any[]): number;


        /**
         * Returns a new list, constructed by applying the supplied function to every element of the supplied list.
         */
        map<T, U>(fn: (x: T) => U, list: T[]): U[];
        map<T, U>(fn: (x: T) => U, obj: any): any; // used in functors
        map<T, U>(fn: (x: T) => U): (list: T[]) => U[];

        /**
         * The mapAccum function behaves like a combination of map and reduce.
         */
        mapAccum<T, U, TResult>(fn: (acc: U, value: T) => [U, TResult], acc: U, list: T[]): [U, TResult[]];
        mapAccum<T, U, TResult>(fn: (acc: U, value: T) => [U, TResult]): (acc: U, list: T[]) => [U, TResult[]];
        mapAccum<T, U, TResult>(fn: (acc: U, value: T) => [U, TResult], acc: U): (list: T[]) => [U, TResult[]];

        /**
         * The mapAccumRight function behaves like a combination of map and reduce.
         */
        mapAccumRight<T, U, TResult>(fn: (acc: U, value: T) => [U, TResult], acc: U, list: T[]): [U, TResult[]];
        mapAccumRight<T, U, TResult>(fn: (acc: U, value: T) => [U, TResult]): (acc: U, list: T[]) => [U, TResult[]];
        mapAccumRight<T, U, TResult>(fn: (acc: U, value: T) => [U, TResult], acc: U): (list: T[]) => [U, TResult[]];

        /**
         * Like map, but but passes additional parameters to the mapping function.
         */
        mapIndexed<T, U>(fn: (val: T, key: number, list: T[]) => U, list: T[]): U[];
        mapIndexed<T, U>(fn: (val: T, key: number, list: T[]) => U): (list: T[]) => U[];


        /**
         * Like mapObj, but but passes additional arguments to the predicate function.
         */
        mergeAll(list: any[]): any;


        /**
         * Returns true if no elements of the list match the predicate, false otherwise.
         */
        none<T>(fn: (a: T) => boolean, list: T[]): boolean;
        none<T>(fn: (a: T) => boolean): (list: T[]) => boolean;

        /**
         * Returns the nth element in a list.
         */
        nth<T>(n: number, list: T[]): T;
        nth<T>(n: number): (list: T[]) => T;

        /**
         * Takes a predicate and a list and returns the pair of lists of elements
         * which do and do not satisfy the predicate, respectively.
         */
        partition(fn: (a: string) => boolean, list: string[]): string[][];
        partition<T>(fn: (a: T) => boolean, list: T[]): T[][];
        partition<T>(fn: (a: T) => boolean): (list: T[]) => T[][];
        partition(fn: (a: string) => boolean): (list: string[]) => string[][];

        /**
         * Returns a new list by plucking the same named property off all objects in the list supplied.
         */
        pluck<T>(p: string|number, list: any[]): T[];
        pluck<T>(p: string|number): (list: any[]) => T[];
        pluck(p: string|number, list: any[]): any[];
        pluck(p: string|number): (list: any[]) => any[];

        /**
         * Returns a new list with the given element at the front, followed by the contents of the
         * list.
         */
        prepend<T>(el: T, list: T[]): T[];
        prepend<T>(el: T): (list: T[]) => T[];

        /**
         * Returns a list of numbers from `from` (inclusive) to `to`
         * (exclusive). In mathematical terms, `range(a, b)` is equivalent to
         * the half-open interval `[a, b)`.
         */
        range(from: number, to: number): number[];
        range(from: number): (to: number) => number[];

        /**
         * Returns a single item by iterating through the list, successively calling the iterator
         * function and passing it an accumulator value and the current value from the array, and
         * then passing the result to the next call.
         */
        reduce<T, TResult>(fn: (acc: TResult, elem: T) => TResult, acc: TResult, list: T[]): TResult;
        reduce<T, TResult>(fn: (acc: TResult, elem: T) => TResult): (acc: TResult, list: T[]) => TResult;
        reduce<T, TResult>(fn: (acc: TResult, elem: T) => TResult, acc: TResult): (list: T[]) => TResult;

        /**
         * Like `reduce`, but passes additional parameters to the predicate function.
         */
        reduceIndexed<T, TResult>(fn: (acc: TResult, elem: T, idx: number, list: T[]) => TResult, acc: TResult, list: T[]): TResult;
        reduceIndexed<T, TResult>(fn: (acc: TResult, elem: T, idx: number, list: T[]) => TResult): (acc: TResult, list: T[]) => TResult;
        reduceIndexed<T, TResult>(fn: (acc: TResult, elem: T, idx: number, list: T[]) => TResult, acc: TResult): (list: T[]) => TResult;

        /**
         * Returns a single item by iterating through the list, successively calling the iterator
         * function and passing it an accumulator value and the current value from the array, and
         * then passing the result to the next call.
         */
        reduceRight<T, TResult>(fn: (acc: TResult, elem: T) => TResult, acc: TResult, list: T[]): TResult;
        reduceRight<T, TResult>(fn: (acc: TResult, elem: T) => TResult): (acc: TResult, list: T[]) => TResult;
        reduceRight<T, TResult>(fn: (acc: TResult, elem: T) => TResult, acc: TResult): (list: T[]) => TResult;

        /**
         * Like `reduceRight`, but passes additional parameters to the predicate function. Moves through
         * the input list from the right to the left.
         */
        reduceRightIndexed<T, TResult>(fn: (acc: TResult, elem: T, idx: Number, list: T[]) => TResult, acc: TResult, list: T[]): TResult;
        reduceRightIndexed<T, TResult>(fn: (acc: TResult, elem: T, idx: Number, list: T[]) => TResult): (acc: TResult, list: T[]) => TResult;
        reduceRightIndexed<T, TResult>(fn: (acc: TResult, elem: T, idx: Number, list: T[]) => TResult, acc: TResult): (list: T[]) => TResult;

        /**
         * Similar to `filter`, except that it keeps only values for which the given predicate
         * function returns falsy.
         */
        reject<T>(fn: (value: T) => boolean, list: T[]): T[];
        reject<T>(fn: (value: T) => boolean): (list: T[]) => T[];

        /**
         * Like `reject`, but passes additional parameters to the predicate function.
         */
        rejectIndexed<T>(fn: (value: T, index: number, list: T[]) => boolean, list: T[]): T[];
        rejectIndexed<T>(fn: (value: T, index: number, list: T[]) => boolean): (list: T[]) => T[];

        /**
         * Removes the sub-list of `list` starting at index `start` and containing `count` elements.
         */
        remove<T>(start: number, count: number, list: T[]): T[];
        remove<T>(start: number): (count: number, list: T[]) => T[];
        remove<T>(start: number, count: number): (list: T[]) => T[];

        /**
         * Returns a fixed list of size n containing a specified identical value.
         */
        repeat<T>(a: T, n: number): T[];
        repeat<T>(a: T): (n: number) => T[];

        /**
         * Returns a new list with the same elements as the original list, just in the reverse order.
         */
        reverse<T>(list: T[]): T[];

        /**
         * Scan is similar to reduce, but returns a list of successively reduced values from the left.
         */
        scan<T, TResult>(fn: (acc: TResult, elem: T) => TResult, acc: TResult, list: T[]): TResult;
        scan<T, TResult>(fn: (acc: TResult, elem: T) => TResult): (acc: TResult, list: T[]) => TResult;
        scan<T, TResult>(fn: (acc: TResult, elem: T) => TResult, acc: TResult): (list: T[]) => TResult;

        /**
         * Returns the elements from `xs` starting at `a` and ending at `b - 1`.
         */
        slice(a: number, b: number, list: string): string;
        slice<T>(a: number, b: number, list: T[]): T[];
        slice<T>(a: number, b: number): (list: string|T[]) => string|T[];
        slice<T>(a: number): (b: number, list: string|T[]) => string|T[];

        /**
         * Returns a copy of the list, sorted according to the comparator function, which should accept two values at a
         * time and return a negative number if the first value is smaller, a positive number if it's larger, and zero
         * if they are equal.
         */
        sort<T>(fn: (a: T, b: T) => number, list: T[]): T[];
        sort<T>(fn: (a: T, b: T) => number): (list: T[]) => T[];

        /**
         * Splits a collection into slices of the specified length.
         */
        splitEvery<T>(a: number, list: T[]): T[][];
        splitEvery<T>(a: number): (list: T[]) => T[][];

        /**
         * Returns all but the first element of a list.
         */
        tail<T>(list: T[]): T[];

        /**
         * Returns a new list containing the first `n` elements of the given list.  If
         * `n > * list.length`, returns a list of `list.length` elements.
         */
        take<T>(n: number, list: T[]): T[];
        take<T>(n: number): (list: T[]) => T[];

        /**
         * Returns a new list containing the first `n` elements of a given list, passing each value
         * to the supplied predicate function, and terminating when the predicate function returns
         * `false`.
         */
        takeWhile<T>(fn: (x: T) => boolean, list: T[]): T[];
        takeWhile<T>(fn: (x: T) => boolean): (list: T[]) => T[];

        /**
         * Calls an input function `n` times, returning an array containing the results of those
         * function calls.
         */
        times<T>(fn: (i: number) => T, n: number): T[];
        times<T>(fn: (i: number) => T): (n: number) => T[];

        /**
         * Initializes a transducer using supplied iterator function. Returns a single item by iterating through the
         * list, successively calling the transformed iterator function and passing it an accumulator value and the
         * current value from the array, and then passing the result to the next call.
         */
        transduce<T,U>(xf: (arg: T[]) => T[], fn: (acc: U[], val: U) => U[], acc: T[], list: T[]): U;
        transduce<T,U>(xf: (arg: T[]) => T[]): (fn: (acc: U[], val: U) => U[], acc: T[], list: T[]) => U;
        transduce<T,U>(xf: (arg: T[]) => T[], fn: (acc: U[], val: U) => U[]): (acc: T[], list: T[]) => U;
        transduce<T,U>(xf: (arg: T[]) => T[], fn: (acc: U[], val: U) => U[], acc: T[]): (list: T[]) => U;

        /**
         * Builds a list from a seed value. Accepts an iterator function, which returns either false
         * to stop iteration or an array of length 2 containing the value to add to the resulting
         * list and the seed to be used in the next call to the iterator function.
         */
        unfold<T, TResult>(fn: (seed: T) => TResult[]|boolean, seed: T): TResult[];
        unfold<T, TResult>(fn: (seed: T) => TResult[]|boolean): (seed: T) => TResult[];

        /**
         * Returns a new list containing only one copy of each element in the original list.
         */
        uniq<T>(list: T[]): T[];

        /**
         * Returns a new list containing only one copy of each element in the original list, based upon the value returned by applying the supplied function to each list element. Prefers the first item if the supplied function produces the same value on two items. R.equals is used for comparison.
         */
        uniqBy<T,U>(fn: (a: T) => U, list: T[]): T[];
        uniqBy<T,U>(fn: (a: T) => U): (list: T[]) => T[];

        /**
         * Returns a new list containing only one copy of each element in the original list, based upon the value
         * returned by applying the supplied predicate to two list elements.
         */
        uniqWith<T,U>(pred: (x: T, y: T) => boolean, list: T[]): T[];
        uniqWith<T,U>(pred: (x: T, y: T) => boolean): (list: T[]) => T[];

        /**
         * Returns a new list by pulling every item at the first level of nesting out, and putting
         * them in a new array.
         */
        unnest<T>(x: T[][]): T[];
        unnest<T>(x: T[]): T[];

        /**
         * Returns a new copy of the array with the element at the provided index replaced with the given value.
         */
        update<T>(index: number, value: T, list: T[]): T[];
        update<T>(index: number, value: T): (list: T[]) => T[];

        /**
         * Creates a new list out of the two supplied by creating each possible pair from the lists.
         */
        xprod<K,V>(as: K[], bs: V[]): KeyValuePair<K,V>[];
        xprod<K,V>(as: K[]): (bs: V[]) => KeyValuePair<K,V>[];

        /**
         * Creates a new list out of the two supplied by pairing up equally-positioned items from
         * both lists. Note: `zip` is equivalent to `zipWith(function(a, b) { return [a, b] })`.
         */
        zip<K,V>(list1: K[], list2: V[]): KeyValuePair<K,V>[];
        zip<K,V>(list1: K[]): (list2: V[]) => KeyValuePair<K,V>[];

        /**
         * Creates a new object out of a list of keys and a list of values.
         */
        // TODO: Dictionary<T> as a return value is to specific, any seems to loose
        zipObj<T>(keys: string[], values: T[]): {[index:string]: T};
        zipObj<T>(keys: string[]): (values: T[]) => {[index:string]: T};

        /**
         * Creates a new list out of the two supplied by applying the function to each
         * equally-positioned pair in the lists.
         */
        zipWith<T, U, TResult>(fn: (x: T, y: U) => TResult, list1: T[], list2: U[]): TResult[];
        zipWith<T, U, TResult>(fn: (x: T, y: U) => TResult, list1: T[]): (list2: U[]) => TResult[];
        zipWith<T, U, TResult>(fn: (x: T, y: U) => TResult): (list1: T[], list2: U[]) => TResult[];

        /*
         * Object category
         */

        /**
         * Makes a shallow clone of an object, setting or overriding the specified property with the given value.
         */
        assoc(prop: string, val: any, obj: any): any;
        assoc(prop: string): (val: any, obj: any) => any;
        assoc(prop: string, val: any): (obj: any) => any;

        /**
         * Makes a shallow clone of an object, setting or overriding the nodes required to create the given path, and
         * placing the specific value at the tail end of that path.
         */
        assocPath(path: string[], val: any, obj: any): any;
        assocPath(path: string[]): (val: any, obj: any) => any;
        assocPath(path: string[], val: any): (obj: any) => any;

        // assoc(prop: string, val: placeholder, obj: any): (val: any) => any;
        // assoc(prop: string, val: any, obj: placeholder): (obj: any) => any;
        // assoc(prop: placeholder, val: placeholder, obj: any): (prop:string, val: any) => any;
        // assoc(prop: placeholder, val: any, obj: placeholder): (prop:string, obj: any) => any;
        // assoc(prop: placeholder, val: any, obj: any): (prop:string) => any;


        /**
         * Creates a deep copy of the value which may contain (nested) Arrays and Objects, Numbers, Strings, Booleans and Dates.
         */
        clone(value: any): any;
        clone(value: any[]): any[];

        /**
         * Creates an object containing a single key:value pair.
         */
        createMapEntry<T>(key: string, val: T): {[index: string]: T};
        createMapEntry<T>(key: placeholder, val: T): (key: string) => {[index: string]: T};
        createMapEntry<T>(key: string): (val: T) => {[index: string]: T};

        /**
         * Returns a new object that does not contain a `prop` property.
         */
        dissoc(prop: string, obj: any): any
        dissoc(prop: string): (obj: any) => any

        /**
         * Returns a new object that does not contain a prop property.
         */
        dissoc(prop: string, obj: any): any;
        dissoc(prop: placeholder, obj: any): (prop: string) => any;
        dissoc(prop: string): (obj: any) => any;

        /**
         * Makes a shallow clone of an object, omitting the property at the given path.
         */
        dissocPath(path: string[], obj: any): any;
        dissocPath(path: string[]): (obj: any) => any;

        /**
         * Reports whether two functions have the same value for the specified property.
         */
        eqProps(prop: string, obj1: any, obj2: any): boolean;
        eqProps(prop: string): (obj1: any, obj2: any) => boolean;
        eqProps(prop: string, obj1: any): (obj2: any) => boolean;

        /**
         * Creates a new object by evolving a shallow copy of object, according to the transformation functions.
         */
        evolve(transformations: {[index: string]: (value: any) => any}, obj: any): any;
        evolve(transformations: {[index: string]: (value: any) => any}): (obj: any) => any;

        /**
         * Returns a list of function names of object's own functions
         */
        functions(obj: any): string[];

        /**
         * Returns a list of function names of object's own and prototype functions
         */
        functionsIn(obj: any): string[];

        /**
         * Returns whether or not an object has an own property with the specified name.
         */
        has(s: string, obj: any): boolean;
        has(s: string): (obj: any) => boolean;
        has(s: placeholder, obj: any): (a: string) => boolean;

        /**
         * Returns whether or not an object or its prototype chain has a property with the specified name
         */
        hasIn(s: string, obj: any): boolean;
        hasIn(s: string): (obj: any) => boolean;
        hasIn(s: placeholder, obj: any): (a: string) => boolean;

        /**
         * Same as R.invertObj, however this accounts for objects with duplicate values by putting the values into an array.
         */
        invert(obj: any): {[index:string]: string[]};

        /**
         * Returns a new object with the keys of the given object as values, and the values of the given object as keys.
         */
        invertObj(obj: any): {[index:string]: string};
        invertObj(obj: {[index: number]: string}): {[index:string]: string};

        /**
         * Returns a list containing the names of all the enumerable own
         * properties of the supplied object.
         */
        keys(x: any): string[];

        /**
         * Returns a list containing the names of all the
         * properties of the supplied object, including prototype properties.
         */
        keysIn(obj: any): string[];


        /**
         * Returns a lens for the given getter and setter functions. The getter
         * "gets" the value of the focus; the setter "sets" the value of the focus.
         * The setter should not mutate the data structure.
         */
        lens<T,U,V>(getter: (s: T) => U, setter: (a: U, s: T) => V): Lens;

        /**
         * Creates a lens that will focus on index n of the source array.
         */
        lensIndex(n: number): Lens;

        /**
         * lensProp creates a lens that will focus on property k of the source object.
         */
        lensProp(str: string): Lens;
        
        /**
         * lensPath Returns a lens whose focus is the specified path.
         */
        lensPath(path: string[]): Lens;
        

        mapObj<T, TResult>(fn: (value: T) => TResult, obj: any): {[index: string]: TResult};
        mapObj<T, TResult>(fn: (value: T) => TResult): (obj: any) => {[index: string]: TResult};

        /**
         * Like mapObj, but but passes additional arguments to the predicate function.
         */
        mapObjIndexed<T, TResult>(fn: (value: T, key: string, obj?: any) => TResult, obj: any): {[index:string]: TResult};
        mapObjIndexed<T, TResult>(fn: (value: T, key: string, obj?: any) => TResult): (obj: any) => {[index:string]: TResult};


        /**
         * Create a new object with the own properties of a
         * merged with the own properties of object b.
         * This function will *not* mutate passed-in objects.
         */
        merge(a: any, b: any): any;
        merge(a: any): (b: any) => any;

        /**
        * Creates a new object with the own properties of the
        * two provided objects. If a key exists in both objects,
        * the provided function is applied to the values associated
        * with the key in each object, with the result being used as
        * the value associated with the key in the returned object.
        * The key will be excluded from the returned object if the
        * resulting value is undefined.
        */
        mergeWith: CurriedFunction3<(l:any, r:any) => any, any, any, any>;

        mergeWithKey: CurriedFunction3<(k:any, l:any, r:any) => any, any, any, any>;

        /**
         * Returns a partial copy of an object omitting the keys specified.
         */
        omit<T>(names: string[], obj: T): T;
        omit<T>(names: string[]): (obj: T) => T;

        /**
         * Returns the result of "setting" the portion of the given data structure
         * focused by the given lens to the given value.
         */
        over<T>(lens: Lens, fn: Arity1Fn, value: T|T[]): T|T[];
        over<T>(lens: Lens, fn: Arity1Fn): (value: T|T[]) => T|T[];
        over<T>(lens: Lens): (fn: Arity1Fn, value: T|T[]) => T|T[];


        /**
         * Retrieve the value at a given path.
         */
        path<T>(path: string[], obj: any): T;
        path<T>(path: placeholder, obj: any): (path: string[]) => T;
        path<T>(path: string[]): (obj: any) => T;

        /**
         * Get the path or the default value
         */
        pathOr: CurriedFunction3<any, Array<string>, Object, any>;

        /**
         * Returns a partial copy of an object containing only the keys specified.  If the key does not exist, the
         * property is ignored.
         */
        pick<T>(names: string[], obj: T): T;
        pick<T>(names: string[]): (obj: T) => T;

        /**
         * Similar to `pick` except that this one includes a `key: undefined` pair for properties that don't exist.
         */
        pickAll<T, U>(names: string[], obj: T): U;
        pickAll<T, U>(names: string[]): (obj: T) => U;

        /**
         * Returns a partial copy of an object containing only the keys that satisfy the supplied predicate.
         */
        pickBy<T,U>(pred: ObjPred, obj: T): U;
        pickBy<T,U>(pred: ObjPred): (obj: T) => U;

        /**
         * Reasonable analog to SQL `select` statement.
         */
        project<T,U>(props: string[], objs: T[]): U[];

        /**
         * Returns a function that when supplied an object returns the indicated property of that object, if it exists.
         */
        prop: CurriedFunction2<string, any, any>;
        //prop(p: string, obj: any): any;
        //prop(p: string): (obj: any) => any;

        /**
         * If the given, non-null object has an own property with the specified name, returns the value of that property.
         * Otherwise returns the provided default value.
         */
        propOr<T,U,V>(val: T, p: string, obj: U): V;
        propOr<T,U,V>(val: T, p: string): (obj: U) => V;
        propOr<T,U,V>(val: T): (p: string, obj: U) => V;

        /**
         * Returns the value at the specified property.
         * The only difference from `prop` is the parameter order.
         */
        props<T>(ps: string[], obj: Dictionary<T>): T[];
        props<T>(ps: string[]): (obj:  Dictionary<T>) => T[];

        /**
         * Returns the result of "setting" the portion of the given data structure focused by the given lens to the
         * given value.
         */
        set<T,U>(lens: Lens, a: U, obj: T): T;
        set<T,U>(lens: Lens, a: U): (obj: T) => T;
        set<T,U>(lens: Lens): (a: U, obj: T) => T;

        /**
         * Converts an object into an array of key, value arrays.
         * Only the object's own properties are used.
         * Note that the order of the output array is not guaranteed to be
         * consistent across different JS platforms.
         */
        toPairs(obj: any): any[][];

        /**
         * Converts an object into an array of key, value arrays.
         * The object's own properties and prototype properties are used.
         * Note that the order of the output array is not guaranteed to be
         * consistent across different JS platforms.
         */
        toPairsIn(obj: any): any[][];

        /**
         * Returns a list of all the enumerable own properties of the supplied object.
         * Note that the order of the output array is not guaranteed across
         * different JS platforms.
         */
        values<T>(obj: {[index: string]: T}): T[];
        values(obj: any): any[];

        /**
         * Returns a list of all the properties, including prototype properties, of the supplied
         * object. Note that the order of the output array is not guaranteed to be consistent across different JS platforms.
         */
        valuesIn(obj: any): any[];

       /**
        * Returns a "view" of the given data structure, determined by the given lens. The lens's focus determines which
        * portion of the data structure is visible.
        */
        view<T,U>(lens: Lens, obj: T): U;

       /**
        * Takes a spec object and a test object and returns true if the test satisfies the spec.
        * Any property on the spec that is not a function is interpreted as an equality
        * relation.
        *
        * If the spec has a property mapped to a function, then `where` evaluates the function, passing in
        * the test object's value for the property in question, as well as the whole test object.
        *
        * `where` is well suited to declarativley expressing constraints for other functions, e.g.,
        * `filter`, `find`, `pickWith`, etc.
        */
        where<T,U>(spec: T, testObj: U): boolean;
        where<T,U>(spec: T): (testObj: U) => boolean;
        where<ObjFunc2,U>(spec: ObjFunc2, testObj: U): boolean;
        where<ObjFunc2,U>(spec: ObjFunc2): (testObj: U) => boolean;

       /**
        * Takes a spec object and a test object; returns true if the test satisfies the spec,
        * false otherwise. An object satisfies the spec if, for each of the spec's own properties,
        * accessing that property of the object gives the same value (in R.eq terms) as accessing
        * that property of the spec.
        */
        whereEq<T,U>(spec: T, obj: U): boolean;
        whereEq<T,U>(spec: T): (obj: U) => boolean;


       /*
        * Function category
        * -----------------
        */

       __: placeholder;

       /**
        * Creates a new list iteration function from an existing one by adding two new parameters to its callback
        * function: the current index, and the entire list.
        */
        addIndex<T, U>(fn: (f: (item: T) => U, list: T[]) => U[])
              : CurriedFunction2<(item: T, idx: number, list?: T[]) => U, T[], U[]>;
       /**
        * Returns a function that always returns the given value.
        */
        always<T>(val: T): () => T;

        /**
         * ap applies a list of functions to a list of values.
         */
        ap<T,U>(fns: ((a: T) => U)[], vs: T[]): U[];
        ap<T,U>(fns: ((a: T) => U)[]): (vs: T[]) => U[];

        /**
         * Applies function fn to the argument list args. This is useful for creating a fixed-arity function from
         * a variadic function. fn should be a bound function if context is significant.
         */
        apply<T, U, TResult>(fn: (arg0: T, ...args: T[]) => TResult, args: U[]): TResult;
        apply<T, U, TResult>(fn: (arg0: T, ...args: T[]) => TResult): (args: U[]) => TResult;

        /**
         * Wraps a function of any arity (including nullary) in a function that accepts exactly 2
         * parameters. Any extraneous parameters will not be passed to the supplied function.
         */
        binary(fn: (...args: any[]) => any): Function;

        /**
         * Creates a function that is bound to a context. Note: R.bind does not provide the additional argument-binding
         * capabilities of Function.prototype.bind.
         */
        bind<T>(thisObj: T, fn: (...args: any[]) => any): (...args: any[]) => any;

        /**
         * Returns the result of calling its first argument with the remaining arguments. This is occasionally useful
         * as a converging function for R.converge: the left branch can produce a function while the right branch
         * produces a value to be passed to that function as an argument.
         */
        call(fn: (...args: any[])=> (...args: any[]) => any, ...args: any[]): any;

        /**
         * Makes a comparator function out of a function that reports whether the first element is less than the second.
         */
        // comparator(pred: (a: any, b: any) => boolean): (x: number, y: number) => number;
        comparator<T>(pred: (a: T, b: T) => boolean): (x: T, y: T) => number;

        /**
         * Performs right-to-left function composition. The rightmost function may have any arity; the remaining
         * functions must be unary.
        */
        compose<V0, T1>(fn0: (x0: V0) => T1): (x0: V0) => T1;
        compose<V0, V1, T1>(fn0: (x0: V0, x1: V1) => T1): (x0: V0, x1: V1) => T1;
        compose<V0, V1, V2, T1>(fn0: (x0: V0, x1: V1, x2: V2) => T1): (x0: V0, x1: V1, x2: V2) => T1;

        compose<V0, T1, T2>(fn1: (x: T1) => T2, fn0: (x0: V0) => T1): (x0: V0) => T2;
        compose<V0, V1, T1, T2>(fn1: (x: T1) => T2, fn0: (x0: V0, x1: V1) => T1): (x0: V0, x1: V1) => T2;
        compose<V0, V1, V2, T1, T2>(fn1: (x: T1) => T2, fn0: (x0: V0, x1: V1, x2: V2) => T1): (x0: V0, x1: V1, x2: V2) => T2;

        compose<V0, T1, T2, T3>(fn2: (x: T2) => T3, fn1: (x: T1) => T2, fn0: (x: V0) => T1): (x: V0) => T3;
        compose<V0, V1, T1, T2, T3>(fn2: (x: T2) => T3, fn1: (x: T1) => T2, fn0: (x0: V0, x1: V1) => T1): (x0: V0, x1: V1) => T3;
        compose<V0, V1, V2, T1, T2, T3>(fn2: (x: T2) => T3, fn1: (x: T1) => T2, fn0: (x0: V0, x1: V1, x2: V2) => T1): (x0: V0, x1: V1, x2: V2) => T3;

        compose<V0, T1, T2, T3, T4>(fn3: (x: T3) => T4, fn2: (x: T2) => T3, fn1: (x: T1) => T2, fn0: (x: V0) => T1): (x: V0) => T4;
        compose<V0, V1, T1, T2, T3, T4>(fn3: (x: T3) => T4, fn2: (x: T2) => T3, fn1: (x: T1) => T2, fn0: (x0: V0, x1: V1) => T1): (x0: V0, x1: V1) => T4;
        compose<V0, V1, V2, T1, T2, T3, T4>(fn3: (x: T3) => T4, fn2: (x: T2) => T3, fn1: (x: T1) => T2, fn0: (x0: V0, x1: V1, x2: V2) => T1): (x0: V0, x1: V1, x2: V2) => T4;

        compose<V0, T1, T2, T3, T4, T5>(fn4: (x: T4) => T5, fn3: (x: T3) => T4, fn2: (x: T2) => T3, fn1: (x: T1) => T2, fn0: (x: V0) => T1): (x: V0) => T5;
        compose<V0, V1, T1, T2, T3, T4, T5>(fn4: (x: T4) => T5, fn3: (x: T3) => T4, fn2: (x: T2) => T3, fn1: (x: T1) => T2, fn0: (x0: V0, x1: V1) => T1): (x0: V0, x1: V1) => T5;
        compose<V0, V1, V2, T1, T2, T3, T4, T5>(fn4: (x: T4) => T5, fn3: (x: T3) => T4, fn2: (x: T2) => T3, fn1: (x: T1) => T2, fn0: (x0: V0, x1: V1, x2: V2) => T1): (x0: V0, x1: V1, x2: V2) => T5;

        compose<V0, T1, T2, T3, T4, T5, T6>(fn5: (x: T5) => T6, fn4: (x: T4) => T5, fn3: (x: T3) => T4, fn2: (x: T2) => T3, fn1: (x: T1) => T2, fn0: (x: V0) => T1): (x: V0) => T6;
        compose<V0, V1, T1, T2, T3, T4, T5, T6>(fn5: (x: T5) => T6, fn4: (x: T4) => T5, fn3: (x: T3) => T4, fn2: (x: T2) => T3, fn1: (x: T1) => T2, fn0: (x0: V0, x1: V1) => T1): (x0: V0, x1: V1) => T6;
        compose<V0, V1, V2, T1, T2, T3, T4, T5, T6>(fn5: (x: T5) => T6, fn4: (x: T4) => T5, fn3: (x: T3) => T4, fn2: (x: T2) => T3, fn1: (x: T1) => T2, fn0: (x0: V0, x1: V1, x2: V2) => T1): (x0: V0, x1: V1, x2: V2) => T6;

        /**
         * TODO composeK
         */

        /**
         * TODO composeP
         */

        construct(fn: Function): Function;

        constructN(n: number, fn: Function): Function;

        /**
         * Accepts a converging function and a list of branching functions and returns a new
         * function. When invoked, this new function is applied to some arguments, each branching
         * function is applied to those same arguments. The results of each branching function
         * are passed as arguments to the converging function to produce the return value.
         */
        converge(after: Function, fns: Function[]): Function;

        curry<T1, T2, TResult>(fn: (a: T1, b: T2) => TResult): CurriedFunction2<T1,T2, TResult>;
        curry<T1, T2, T3, TResult>(fn: (a: T1, b: T2, c: T3) => TResult): CurriedFunction3<T1,T2, T3, TResult>;
        curry<T1, T2, T3, T4, TResult>(fn: (a: T1, b: T2, c: T3, d: T4) => TResult): CurriedFunction4<T1,T2, T3, T4, TResult>;
        curry<T1, T2, T3, T4, T5, TResult>(fn: (a: T1, b: T2, c: T3, d: T4, e: T5) => TResult): CurriedFunction5<T1,T2, T3, T4, T5, TResult>;
        curry<T1, T2, T3, T4, T5, T6, TResult>(fn: (a: T1, b: T2, c: T3, d: T4, e: T5, f: T6) => TResult): CurriedFunction6<T1,T2, T3, T4, T5, T6, TResult>;
        curry(fn: Function): Function;

        curryN(length: number, fn: (...args: any[]) => any): AnyCurriedFunction;

        /**
         * `empty` wraps any object in an array. This implementation is compatible with the
         * Fantasy-land Monoid spec, and will work with types that implement that spec.
         */
        empty(x: any): any[];

        F(): boolean;

        /**
         * Returns a new function much like the supplied one, except that the first two arguments'
         * order is reversed.
         */
        flip<T,U,TResult>(fn: (arg0: T, arg1: U) => TResult): (arg1: U, arg0?: T) => TResult;
        flip<T,U,TResult>(fn: (arg0: T, arg1: U, ...args: any[]) => TResult): (arg1: U, arg0?: T, ...args: any[]) => TResult;

        /**
         * A function that does nothing but return the parameter supplied to it. Good as a default
         * or placeholder function.
         */
        identity(a: any): any;

        /**
         * Turns a named method of an object (or object prototype) into a function that can be
         * called directly. Passing the optional `len` parameter restricts the returned function to
         * the initial `len` parameters of the method.
         *
         * The returned function is curried and accepts `len + 1` parameters (or `method.length + 1`
         * when `len` is not specified), and the final parameter is the target object.
         */
        invoker(arity: number, method: string): AnyCurriedFunction;

        lift(fn: Function, ...args: any[]): any;

        liftN(n: number, fn: Function, ...args: any[]): any;


        memoize(fn: Function): Function;

        nAry(n: number, fn: (...arg: any[]) => any): Function;

        /**
         * TODO nthArg
         */

        /**
        * Creates an object containing a single key:value pair.
        */
        objOf<T>(k:string, a: T): {[index:string]: T};

        /**
        * Returns a singleton array containing the value provided.
        */
        of<T>(x: T): T[];
        of<T>(x: T[]): T[][];

        once(fn: Function): Function;


        /**
         * Accepts as its arguments a function and any number of values and returns a function that,
         * when invoked, calls the original function with all of the values prepended to the
         * original function's arguments list. In some libraries this function is named `applyLeft`.
         */
        partial(fn: Function, ...args: any[]): Function;

        /**
         * Accepts as its arguments a function and any number of values and returns a function that,
         * when invoked, calls the original function with all of the values appended to the original
         * function's arguments list.
         */
        partialRight(fn: Function, ...args: any[]): Function;

        /**
         * Creates a new function that runs each of the functions supplied as parameters in turn,
         * passing the return value of each function invocation to the next function invocation,
         * beginning with whatever arguments were passed to the initial invocation.
         */
        pipe<V0, T1>(fn0: (x0: V0) => T1): (x0: V0) => T1;
        pipe<V0, V1, T1>(fn0: (x0: V0, x1: V1) => T1): (x0: V0, x1: V1) => T1;
        pipe<V0, V1, V2, T1>(fn0: (x0: V0, x1: V1, x2: V2) => T1): (x0: V0, x1: V1, x2: V2) => T1;

        pipe<V0, T1, T2>(fn0: (x0: V0) => T1, fn1: (x: T1) => T2): (x0: V0) => T2;
        pipe<V0, V1, T1, T2>(fn0: (x0: V0, x1: V1) => T1, fn1: (x: T1) => T2): (x0: V0, x1: V1) => T2;
        pipe<V0, V1, V2, T1, T2>(fn0: (x0: V0, x1: V1, x2: V2) => T1, fn1: (x: T1) => T2): (x0: V0, x1: V1, x2: V2) => T2;

        pipe<V0, T1, T2, T3>(fn0: (x: V0) => T1, fn1: (x: T1) => T2, fn2: (x: T2) => T3): (x: V0) => T3;
        pipe<V0, V1, T1, T2, T3>(fn0: (x0: V0, x1: V1) => T1, fn1: (x: T1) => T2, fn2: (x: T2) => T3): (x0: V0, x1: V1) => T3;
        pipe<V0, V1, V2, T1, T2, T3>(fn0: (x0: V0, x1: V1, x2: V2) => T1, fn1: (x: T1) => T2, fn2: (x: T2) => T3): (x0: V0, x1: V1, x2: V2) => T3;

        pipe<V0, T1, T2, T3, T4>(fn0: (x: V0) => T1, fn1: (x: T1) => T2, fn2: (x: T2) => T3, fn3: (x: T3) => T4): (x: V0) => T4;
        pipe<V0, V1, T1, T2, T3, T4>(fn0: (x0: V0, x1: V1) => T1, fn1: (x: T1) => T2, fn2: (x: T2) => T3, fn3: (x: T3) => T4): (x0: V0, x1: V1) => T4;
        pipe<V0, V1, V2, T1, T2, T3, T4>(fn0: (x0: V0, x1: V1, x2: V2) => T1, fn1: (x: T1) => T2, fn2: (x: T2) => T3, fn3: (x: T3) => T4): (x0: V0, x1: V1, x2: V2) => T4;

        pipe<V0, T1, T2, T3, T4, T5>(fn0: (x: V0) => T1, fn1: (x: T1) => T2, fn2: (x: T2) => T3, fn3: (x: T3) => T4, fn4: (x: T4) => T5): (x: V0) => T5;
        pipe<V0, V1, T1, T2, T3, T4, T5>(fn0: (x0: V0, x1: V1) => T1, fn1: (x: T1) => T2, fn2: (x: T2) => T3, fn3: (x: T3) => T4, fn4: (x: T4) => T5): (x0: V0, x1: V1) => T5;
        pipe<V0, V1, V2, T1, T2, T3, T4, T5>(fn0: (x0: V0, x1: V1, x2: V2) => T1, fn1: (x: T1) => T2, fn2: (x: T2) => T3, fn3: (x: T3) => T4, fn4: (x: T4) => T5): (x0: V0, x1: V1, x2: V2) => T5;

        pipe<V0, T1, T2, T3, T4, T5, T6>(fn0: (x: V0) => T1, fn1: (x: T1) => T2, fn2: (x: T2) => T3, fn3: (x: T3) => T4, fn4: (x: T4) => T5, fn5: (x: T5) => T6): (x: V0) => T6;
        pipe<V0, V1, T1, T2, T3, T4, T5, T6>(fn0: (x0: V0, x1: V1) => T1, fn1: (x: T1) => T2, fn2: (x: T2) => T3, fn3: (x: T3) => T4, fn4: (x: T4) => T5, fn5: (x: T5) => T6): (x0: V0, x1: V1) => T6;
        pipe<V0, V1, V2, T1, T2, T3, T4, T5, T6>(fn0: (x0: V0, x1: V1, x2: V2) => T1, fn1: (x: T1) => T2, fn2: (x: T2) => T3, fn3: (x: T3) => T4, fn4: (x: T4) => T5, fn5: (x: T5) => T6): (x0: V0, x1: V1, x2: V2) => T6;

        pipe<V0, T1, T2, T3, T4, T5, T6, T7>(fn0: (x: V0) => T1, fn1: (x: T1) => T2, fn2: (x: T2) => T3, fn3: (x: T3) => T4, fn4: (x: T4) => T5, fn5: (x: T5) => T6, fn: (x: T6) => T7): (x: V0) => T7;
        pipe<V0, V1, T1, T2, T3, T4, T5, T6, T7>(fn0: (x0: V0, x1: V1) => T1, fn1: (x: T1) => T2, fn2: (x: T2) => T3, fn3: (x: T3) => T4, fn4: (x: T4) => T5, fn5: (x: T5) => T6, fn6: (x: T6) => T7): (x0: V0, x1: V1) => T7;
        pipe<V0, V1, V2, T1, T2, T3, T4, T5, T6, T7>(fn0: (x0: V0, x1: V1, x2: V2) => T1, fn1: (x: T1) => T2, fn2: (x: T2) => T3, fn3: (x: T3) => T4, fn4: (x: T4) => T5, fn5: (x: T5) => T6, fn6: (x: T6) => T7): (x0: V0, x1: V1, x2: V2) => T7;

        pipe<V0, T1, T2, T3, T4, T5, T6, T7, T8>(fn0: (x: V0) => T1, fn1: (x: T1) => T2, fn2: (x: T2) => T3, fn3: (x: T3) => T4, fn4: (x: T4) => T5, fn5: (x: T5) => T6, fn6: (x: T6) => T7, fn: (x: T7) => T8): (x: V0) => T8;
        pipe<V0, V1, T1, T2, T3, T4, T5, T6, T7, T8>(fn0: (x0: V0, x1: V1) => T1, fn1: (x: T1) => T2, fn2: (x: T2) => T3, fn3: (x: T3) => T4, fn4: (x: T4) => T5, fn5: (x: T5) => T6, fn6: (x: T5) => T6, fn7: (x: T7) => T8): (x0: V0, x1: V1) => T8;
        pipe<V0, V1, V2, T1, T2, T3, T4, T5, T6, T7, T8>(fn0: (x0: V0, x1: V1, x2: V2) => T1, fn1: (x: T1) => T2, fn2: (x: T2) => T3, fn3: (x: T3) => T4, fn4: (x: T4) => T5, fn5: (x: T5) => T6, fn6: (x: T5) => T6, fn7: (x: T7) => T8): (x0: V0, x1: V1, x2: V2) => T8;

        /**
         * The function to call with x. The return value of fn will be thrown away.
         */
        tap<T>(fn: (a: T) => any, value: T): T;
        tap<T>(fn: (a: T) => any): (value: T) => T;


        // Object Functions
        // ----------------
        //
        // These functions operate on plain Javascript object, adding simple functions to test properties on these
        // objects.  Many of these are of most use in conjunction with the list functions, operating on lists of
        // objects.


        op(fn: (a: any, b: any) => any): Function;

        substring(indexA: number, indexB: number, str: string): string;
        substringFrom(indexA: number, str: string): string;
        substringTo(indexA: number, str: string): string;

        isArrayLike(val: any): boolean;

        op(fn: Function): Function;



        unary<T>(fn: (a: T, ...args: any[]) => any): (a: T) => any




        /**
         * Accepts a function fn and a list of transformer functions and returns a new curried function.
         * When the new function is invoked, it calls the function fn with parameters consisting of the
         * result of calling each supplied handler on successive arguments to the new function.
         *
         * If more arguments are passed to the returned function than transformer functions, those arguments
         * are passed directly to fn as additional parameters. If you expect additional arguments that don't
         * need to be transformed, although you can ignore them, it's best to pass an identity function so
         * that the new function reports the correct arity.
         */
        useWith(fn: Function, transformers: Function[]): Function;








        /**
         * Returns a fixed list of size `n` containing a specified identical value.
         */
        repeatN<T>(value: T, n: number): T[];


        wrap(fn: Function, wrapper: Function): Function;




        /*
         * List category
         * -------------
         */



        // flip<T,U,TResult>(fn: (arg0: T, arg1: U, ...args: any[]) => TResult): (arg1: U, arg0: T) => ((...args: any[]) => TResult);
        // flip<T,U,TResult>(fn: (arg0: T, arg1: U, ...args: any[]) => TResult): (arg1: U) => ((arg0: T, ...args: any[]) => TResult);




        /**
         * `of` wraps any object in an Array. This implementation is compatible with the
         * Fantasy-land Applicative spec, and will work with types that implement that spec.
         * Note this `of` is different from the ES6 `of`; See
         * https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/of
         */
        of(x: any): any[];






        /**
         * Returns a new list by pulling every item out of it (and all its sub-arrays) and putting
         * them in a new array, depth-first.
         */
        // checked
        flatten(x: any[][]): any[];
        flatten(x: any[]): any[];

        /**
         * Calls the specified function on the supplied object. Any additional arguments
         * after `fn` and `obj` are passed in to `fn`. If no additional arguments are passed to `func`,
         * `fn` is invoked with no arguments.
         */
        func(funcName: string , obj: any): any;



        // Miscellaneous Functions
        // -----------------------
        //
        // A few functions in need of a good home.

        // --------

        /**
         * Expose the functions from ramda as properties of another object.
         * If the provided object is the global object then the ramda
         * functions become global functions.
         * Warning: This function *will* mutate the object provided.
         */
        installTo(obj: any): any;


        /**
         * See if an object (`val`) is an instance of the supplied constructor.
         * This function will check up the inheritance chain, if any.
         */
        is(ctor: any, val: any): boolean;
        is(ctor: any): (val: any) => boolean;


        /**
         * Checks if the input value is null or undefined.
         */
        isNil(value: any): boolean;


        /**
         * A function that always returns `0`. Any passed in parameters are ignored.
         */
        alwaysZero(): number;


        /**
         * A function that always returns `false`. Any passed in parameters are ignored.
         */
        alwaysFalse(): boolean;


        /**
         * A function that always returns `true`. Any passed in parameters are ignored.
         */
        alwaysTrue(): boolean;

        /**
         * Logic Category
         * ---------------
         */

        /**
         * Given a list of predicates, returns a new predicate that will be true exactly when all of them are.
         */
        allPass(preds: Pred[]): Pred;

        /**
         * A function that returns the first argument if it's falsy otherwise the second argument. Note that this is
         * NOT short-circuited, meaning that if expressions are passed they are both evaluated.
         */
        and<T extends {and?: Function;}>(fn1: T, val2: boolean|any): boolean;
        and<T extends {and?: Function;}>(fn1: T): (val2: boolean|any) => boolean;

        /**
         * Given a list of predicates returns a new predicate that will be true exactly when any one of them is.
         */
        anyPass(preds: Pred[]): Pred;

        /**
         * A function wrapping calls to the two functions in an && operation, returning the result of the first function
         * if it is false-y and the result of the second function otherwise. Note that this is short-circuited, meaning
         * that the second function will not be invoked if the first returns a false-y value.
         */
        both(pred1: Pred, pred2: Pred): Pred;
        both(pred1: Pred): (pred2: Pred) => Pred;

        /**
         * Takes a function f and returns a function g such that:
         * - applying g to zero or more arguments will give true if applying the same arguments to f gives
         *   a logical false value; and
         * - applying g to zero or more arguments will give false if applying the same arguments to f gives
         *   a logical true value.
         */
        complement(pred: (...args: any[]) => boolean): (...args: any[]) => boolean

        /**
         * Returns a function, fn, which encapsulates if/else-if/else logic. R.cond takes a list of [predicate, transform] pairs.
         * All of the arguments to fn are applied to each of the predicates in turn until one returns a "truthy" value, at which
         * point fn returns the result of applying its arguments to the corresponding transformer. If none of the predicates
         * matches, fn returns undefined.
         */
        cond(fns: [Pred, Function][]): Function;

        /**
         * Returns the second argument if it is not null or undefined. If it is null or undefined, the
         * first (default) argument is returned.
         */
        defaultTo<T,U>(a: T, b: U): T|U
        defaultTo<T>(a: T): <U>(b: U) => T|U

        /**
         * A function wrapping calls to the two functions in an || operation, returning the result of the first
         * function if it is truth-y and the result of the second function otherwise. Note that this is
         * short-circuited, meaning that the second function will not be invoked if the first returns a truth-y value.
         */
        either(pred1: Pred, pred2: Pred): Pred;
        either(pred1: Pred): (pred2: Pred) => Pred;

        /**
         * Creates a function that will process either the onTrue or the onFalse function depending upon the result
         * of the condition predicate.
         */
        ifElse(fn: Pred, onTrue: Arity1Fn, onFalse: Arity1Fn): Arity1Fn;

        /**
         * Reports whether the list has zero elements.
         */
        isEmpty(value: string|any[]): boolean;

        /**
         * A function wrapping a call to the given function in a `!` operation.  It will return `true` when the
         * underlying function would return a false-y value, and `false` when it would return a truth-y one.
         */
        not(value: any): boolean;

        /**
         * A function that returns the first truthy of two arguments otherwise the last argument. Note that this is
         * NOT short-circuited, meaning that if expressions are passed they are both evaluated.
         * Dispatches to the or method of the first argument if applicable.
         */
        or<T, U>(a: T, b: U): T|U;
        or<T>(a: T): <U>(b: U) => T|U;
        or<T extends {or?: Function;}, U>(fn1: T, val2: U): T|U;
        or<T extends {or?: Function;}>(fn1: T): <U>(val2: U) => T|U;

        /**
         * Verify that the property at the path satisfies the predicate
         */
        pathSatisfies: CurriedFunction3<(prop: any)=>boolean, string[], any, boolean>;

        /**
         * Verify that the property satisfies the predicate
         */
        propSatisfies: CurriedFunction3<(prop: any)=>boolean, string, any, boolean>;

        /**
         * Opposite of when
         */
        unless: CurriedFunction2<(test: any)=>boolean, (test: any)=>any, any>;

        /**
         * When the predicate function returns true, the function is mutated using the second funciton.
         * Otherwise the input is returned as is.
         */
        when: CurriedFunction2<(test: any)=>boolean, (test: any)=>any, any>;


        /**
         * Math category
         * -------------
         */

        /**
         * Adds two numbers (or strings). Equivalent to a + b but curried.
         */
        add(a: number, b: number): number;
        add(a: string, b: string): string;
        add(a: number): (b: number) => number;
        add(a: string): (b: string) => string;

        /**
         * Decrements its argument.
         */
        dec(n: number): number;

        /**
         * Divides two numbers. Equivalent to a / b.
         */
        divide(a: number, b: number): number;
        divide(a: number): (b: number) => number;
        divide(a: placeholder, b: number): (b: number) => number;

        /**
         * Returns true if the first parameter is greater than the second.
         */
        gt(a: number, b: number): boolean;
        gt(a: number): (b: number) => boolean;
        gt(a: placeholder, b: number): (b: number) => boolean;

        /**
         * Returns true if the first parameter is greater than or equal to the second.
         */
        gte(a: number, b: number): boolean;
        gte(a: number): (b: number) => boolean;
        gte(a: placeholder, b: number): (b: number) => boolean;

        /**
         * Increments its argument.
         */
        inc(n: number): number;

        /**
         * Returns true if the input value is NaN.
         */
        isNaN(x: any): boolean;

        /**
         * Returns true if the first parameter is less than the second.
         */
        lt(a: number, b: number): boolean;
        lt(a: number): (b: number) => boolean;
        lt(a: placeholder, b: number): (b: number) => boolean;

        /**
         * Returns true if the first parameter is less than or equal to the second.
         */
        lte(a: number, b: number): boolean;
        lte(a: number): (b: number) => boolean;
        lte(a: placeholder, b: number): (b: number) => boolean;

        /**
         * mathMod behaves like the modulo operator should mathematically, unlike the `%`
         * operator (and by extension, R.modulo). So while "-17 % 5" is -2,
         * mathMod(-17, 5) is 3. mathMod requires Integer arguments, and returns NaN
         * when the modulus is zero or negative.
         */
        mathMod(a: number, b: number): number;
        mathMod(a: number): (b: number) => number;
        mathMod(a: placeholder, b: number): (a: number) => number;

        /**
         * Returns the larger of its two arguments.
         */
        max(a: number, b: number): number;
        max(a: number): (b: number) => number;

        /**
         * Determines the largest of a list of items as determined by pairwise comparisons from the supplied comparator.
         */
        maxBy<T>(keyFn: (a: T) => number, list: T[]): T;
        maxBy<T>(keyFn: (a: T) => number): (list: T[]) => T;

        /**
         * Returns the smaller of its two arguments.
         */
        min(a: number, b: number): number;
        min(a: number): (b: number) => number;

        /**
         * Determines the smallest of a list of items as determined by pairwise comparisons from the supplied comparator.
         */
        minBy<T>(keyFn: (a: T) => number, list: T[]): T;
        minBy<T>(keyFn: (a: T) => number): (list: T[]) => T;

        /**
         * Divides the second parameter by the first and returns the remainder.
         * The flipped version (`moduloBy`) may be more useful curried.
         * Note that this functions preserves the JavaScript-style behavior for
         * modulo. For mathematical modulo see `mathMod`
         */
        modulo(a: number, b: number): number;
        modulo(a: placeholder, b: number): (a: number) => number;
        modulo(a: number): (b: number) => number;

        /**
         * Multiplies two numbers. Equivalent to a * b but curried.
         */
        multiply(a: number, b: number): number;
        multiply(a: number): (b: number) => number;
        multiply(a: placeholder, b: number): (a: number) => number;

        /**
         * Negates its argument.
         */
        negate(n: number): number;

        /**
         * Multiplies together all the elements of a list.
         */
        product(list: number[]): number;

        /**
         * Subtracts two numbers. Equivalent to `a - b` but curried.
         */
        subtract(a: number, b: number): number;
        subtract(a: placeholder, b: number): (a: number) => number;
        subtract(a: number): (b: number) => number;

        /**
         * Adds together all the elements of a list.
         */
        sum(list: number[]): number;

        /*
         * String Functions
         */

        /**
         * Returns a string containing the characters of str from fromIndex (inclusive) to toIndex (exclusive).
         */
        substring(indexA: number, indexB: number, str: string): string;
        substring(indexA: number): (indexB: number, str: string) => string;
        substring(indexA: number, indexB: number): (str: string) => string;


        /**
         * The trailing substring of a String starting with the nth character:
         */
        substringFrom(indexA: number, str: string): string;
        substringFrom(indexA: number): (str: string) => string;

        /**
         * Replace a substring or regex match in a string with a replacement.
         */
        replace(pattern: RegExp, replacement: string, str: string): string;
        replace(pattern: RegExp, replacement: string): (str: string) => string;
        replace(pattern: RegExp): (replacement: string) => (str: string) => string;
        replace(pattern: String, replacement: string, str: string): string;
        replace(pattern: String, replacement: string): (str: string) => string;
        replace(pattern: String): (replacement: string) => (str: string) => string;

        /**
         * Returns a string containing the first toIndex characters of str.
         */
        substringTo(toIndex: number, str: string): string;
        substringTo(toIndex: number): (str: string) => string;


        /**
         * Returns the nth character of the given string.
         */
        nthChar(index: number, str: string): string;


        /**
         * Returns the character code of the nth character of the given string.
         */
        nthCharCode(index: number, str: string): number;


        /**
         * Tests a regular expression agains a String
         */
        match(regexp: RegExp, str: string): any[];


        /**
         * Finds the first index of a substring in a string, returning -1 if it's not present
         */
        strIndexOf(c: string, str: string): number;


        /**
         * Finds the last index of a substring in a string, returning -1 if it's not present
         */
        strLastIndexOf(c: string, str: string): number;


        /**
         * The upper case version of a string.
         */
        toUpper(str: string): string;


        /**
         * Removes (strips) whitespace from both ends of the string.
         */
        trim(str: string): string;


        /**
         * The lower case version of a string.
         */
        toLower(str: string): string;


        /**
         * Splits a string into an array of strings based on the given
         * separator.
         */

        split(sep: string): (str: string) => string[];
        split(sep: RegExp): (str: string) => string[];
        split(sep: string, str: string): string[];
        split(sep: RegExp, str: string): string[];



        // Data Analysis and Grouping Functions
        // ------------------------------------
        //
        // Functions performing SQL-like actions on lists of objects.  These do
        // not have any SQL-like optimizations performed on them, however.

        // --------

        /*
         * Relation category
         */

        /**
         * Counts the elements of a list according to how many match each value
         * of a key generated by the supplied function. Returns an object
         * mapping the keys produced by `fn` to the number of occurrences in
         * the list. Note that all keys are coerced to strings because of how
         * JavaScript objects work.
         */
        countBy(fn: (a: any) => string|number, list: any[]): any;
        countBy(fn: (a: any) => string|number): (list: any[]) => any;

        /**
         * Finds the set (i.e. no duplicates) of all elements in the first list not contained in the second list.
         */
        difference<T>(list1: T[], list2: T[]): T[];
        difference<T>(list1: T[]): (list2: T[]) => T[];


        /**
         * Finds the set (i.e. no duplicates) of all elements in the first list not contained in the second list.
         * Duplication is determined according to the value returned by applying the supplied predicate to two list
         * elements.
         */
        differenceWith<T>(pred: (a: T, b: T) => boolean, list1: T[], list2: T[]): T[];

        /**
         * Tests if two items are equal.  Equality is strict here, meaning reference equality for objects and
         * non-coercing equality for primitives.
         */
        eq<T>(a: T, b: T): boolean;
        eq<T>(a: T): (b: T) => boolean;

        /**
         * Returns true if its arguments are equivalent, false otherwise. Dispatches to an equals method if present.
         * Handles cyclical data structures.
         */
        equals<T>(a: T, b: T): boolean;
        equals<T>(a: T): (b: T) => boolean;


        /**
         * Returns true if its arguments are identical, false otherwise. Values are identical if they reference the
         * same memory. NaN is identical to NaN; 0 and -0 are not identical.
         */
        identical<T>(a: T, b: T): boolean;
        identical<T>(a: T): (b: T) => boolean;


        /**
         * Combines two lists into a set (i.e. no duplicates) composed of those elements common to both lists.
         */
        intersection<T>(list1: T[], list2: T[]): T[];


        /**
         * Combines two lists into a set (i.e. no duplicates) composed of those
         * elements common to both lists.  Duplication is determined according
         * to the value returned by applying the supplied predicate to two list
         * elements.
         */
        intersectionWith<T>(pred: (a: T, b: T) => boolean, list1: T[], list2: T[]): T[];

        /**
         * Determines whether a nested path on an object has a specific value,
         * in `R.equals` terms. Most likely used to filter a list.
         */
        pathEq(path: string[], val: any, obj: any): boolean;
        pathEq(path: string[], val: any): (obj: any) => boolean;
        pathEq(path: string[]): (val: any, obj: any) => boolean;
        pathEq(path: string[]): (val: any) => (obj: any) => boolean;

        /**
         * Determines whether the given property of an object has a specific
         * value according to strict equality (`===`).  Most likely used to
         * filter a list.
         */
        propEq<T>(name: string, val: T, obj: any): boolean;
        propEq<T>(name: number, val: T, obj: any): boolean;
        propEq<T>(name: string, val: T): (...args: any[]) => boolean;
        propEq<T>(name: number, val: T): (...args: any[]) => boolean;
        propEq<T>(name: string): (val: T, ...args: any[]) => boolean;
        propEq<T>(name: number): (val: T, ...args: any[]) => boolean;

        /**
         * Sorts the list according to a key generated by the supplied function.
         */
        sortBy<T>(fn: (a: any) => string, list: T[]): T[];
        sortBy<T>(__: placeholder, list: T[]): T[];
        sortBy<T>(fn: (a: any) => string): (list: T[]) => T[];

        /**
         * Combines two lists into a set (i.e. no duplicates) composed of the
         * elements of each list.
         */
        union<T>(as: T[], bs: T[]): T[];

        /**
         * Combines two lists into a set (i.e. no duplicates) composed of the elements of each list.  Duplication is
         * determined according to the value returned by applying the supplied predicate to two list elements.
         */
        unionWith<T>(pred: (a: T, b: T) => boolean, list1: T[], list2: T[]): T[];

        eq<T,U>(a: T, b: U): boolean;

        T(): boolean;

    }
}

export = R;