declare type PropertyKey = string | number | symbol;

interface Symbol {
    /** Returns a string representation of an object. */
    toString(): string;

    /** Returns the primitive value of the specified object. */
    valueOf(): Object;

    [Symbol.toStringTag]: string;
}

interface SymbolConstructor {
    /** 
      * A reference to the prototype. 
      */
    prototype: Symbol;

    /**
      * Returns a new unique Symbol value.
      * @param  description Description of the new Symbol object.
      */
    (description?: string|number): symbol;

    /**
      * Returns a Symbol object from the global symbol registry matching the given key if found. 
      * Otherwise, returns a new symbol with this key.
      * @param key key to search for.
      */
    for(key: string): symbol;

    /**
      * Returns a key from the global symbol registry matching the given Symbol if found. 
      * Otherwise, returns a undefined.
      * @param sym Symbol to find the key for.
      */
    keyFor(sym: symbol): string;

    // Well-known Symbols

    /** 
      * A method that determines if a constructor object recognizes an object as one of the 
      * constructor’s instances. Called by the semantics of the instanceof operator. 
      */
    hasInstance: symbol;

    /** 
      * A Boolean value that if true indicates that an object should flatten to its array elements
      * by Array.prototype.concat.
      */
    isConcatSpreadable: symbol;

    /** 
      * A method that returns the default iterator for an object. Called by the semantics of the 
      * for-of statement.
      */
    iterator: symbol;

    /**
      * A regular expression method that matches the regular expression against a string. Called 
      * by the String.prototype.match method. 
      */
    match: symbol;

    /** 
      * A regular expression method that replaces matched substrings of a string. Called by the 
      * String.prototype.replace method.
      */
    replace: symbol;

    /**
      * A regular expression method that returns the index within a string that matches the 
      * regular expression. Called by the String.prototype.search method.
      */
    search: symbol;

    /** 
      * A function valued property that is the constructor function that is used to create 
      * derived objects.
      */
    species: symbol;

    /**
      * A regular expression method that splits a string at the indices that match the regular 
      * expression. Called by the String.prototype.split method.
      */
    split: symbol;

    /** 
      * A method that converts an object to a corresponding primitive value.
      * Called by the ToPrimitive abstract operation.
      */
    toPrimitive: symbol;

    /** 
      * A String value that is used in the creation of the default string description of an object.
      * Called by the built-in method Object.prototype.toString.
      */
    toStringTag: symbol;

    /**
      * An Object whose own property names are property names that are excluded from the 'with'
      * environment bindings of the associated objects.
      */
    unscopables: symbol;
}
declare var Symbol: SymbolConstructor;

interface Object {
    /**
      * Determines whether an object has a property with the specified name. 
      * @param v A property name.
      */
    hasOwnProperty(v: PropertyKey): boolean;

    /** 
      * Determines whether a specified property is enumerable.
      * @param v A property name.
      */
    propertyIsEnumerable(v: PropertyKey): boolean;
}

interface ObjectConstructor {
    /**
      * Copy the values of all of the enumerable own properties from one or more source objects to a 
      * target object. Returns the target object.
      * @param target The target object to copy to.
      * @param source The source object from which to copy properties.
      */
    assign<T, U>(target: T, source: U): T & U;

    /**
      * Copy the values of all of the enumerable own properties from one or more source objects to a 
      * target object. Returns the target object.
      * @param target The target object to copy to.
      * @param source1 The first source object from which to copy properties.
      * @param source2 The second source object from which to copy properties.
      */
    assign<T, U, V>(target: T, source1: U, source2: V): T & U & V;

    /**
      * Copy the values of all of the enumerable own properties from one or more source objects to a 
      * target object. Returns the target object.
      * @param target The target object to copy to.
      * @param source1 The first source object from which to copy properties.
      * @param source2 The second source object from which to copy properties.
      * @param source3 The third source object from which to copy properties.
      */
    assign<T, U, V, W>(target: T, source1: U, source2: V, source3: W): T & U & V & W;

    /**
      * Copy the values of all of the enumerable own properties from one or more source objects to a 
      * target object. Returns the target object.
      * @param target The target object to copy to.
      * @param sources One or more source objects from which to copy properties
      */
    assign(target: any, ...sources: any[]): any;

    /**
      * Returns an array of all symbol properties found directly on object o.
      * @param o Object to retrieve the symbols from.
      */
    getOwnPropertySymbols(o: any): symbol[];

    /**
      * Returns true if the values are the same value, false otherwise.
      * @param value1 The first value.
      * @param value2 The second value.
      */
    is(value1: any, value2: any): boolean;

    /**
      * Sets the prototype of a specified object o to  object proto or null. Returns the object o.
      * @param o The object to change its prototype.
      * @param proto The value of the new prototype or null.
      */
    setPrototypeOf(o: any, proto: any): any;

    /**
      * Gets the own property descriptor of the specified object. 
      * An own property descriptor is one that is defined directly on the object and is not 
      * inherited from the object's prototype. 
      * @param o Object that contains the property.
      * @param p Name of the property.
    */
    getOwnPropertyDescriptor(o: any, propertyKey: PropertyKey): PropertyDescriptor;

    /**
      * Adds a property to an object, or modifies attributes of an existing property. 
      * @param o Object on which to add or modify the property. This can be a native JavaScript 
      * object (that is, a user-defined object or a built in object) or a DOM object.
      * @param p The property name.
      * @param attributes Descriptor for the property. It can be for a data property or an accessor
      *  property.
      */
    defineProperty(o: any, propertyKey: PropertyKey, attributes: PropertyDescriptor): any;
}

interface Function {
    /**
      * Returns the name of the function. Function names are read-only and can not be changed.
      */
    name: string;

    /**
     * Determines whether the given value inherits from this function if this function was used
     * as a constructor function.
     *
     * A constructor function can control which objects are recognized as its instances by
     * 'instanceof' by overriding this method.
     */
    [Symbol.hasInstance](value: any): boolean;
}

interface NumberConstructor {
    /**
      * The value of Number.EPSILON is the difference between 1 and the smallest value greater than 1
      * that is representable as a Number value, which is approximately: 
      * 2.2204460492503130808472633361816 x 10‍−‍16.
      */
    EPSILON: number;

    /**
      * Returns true if passed value is finite.
      * Unlike the global isFininte, Number.isFinite doesn't forcibly convert the parameter to a 
      * number. Only finite values of the type number, result in true.
      * @param number A numeric value.
      */
    isFinite(number: number): boolean;

    /**
      * Returns true if the value passed is an integer, false otherwise.
      * @param number A numeric value.
      */
    isInteger(number: number): boolean;

    /**
      * Returns a Boolean value that indicates whether a value is the reserved value NaN (not a 
      * number). Unlike the global isNaN(), Number.isNaN() doesn't forcefully convert the parameter
      * to a number. Only values of the type number, that are also NaN, result in true.
      * @param number A numeric value.
      */
    isNaN(number: number): boolean;

    /**
      * Returns true if the value passed is a safe integer.
      * @param number A numeric value.
      */
    isSafeInteger(number: number): boolean;

    /** 
      * The value of the largest integer n such that n and n + 1 are both exactly representable as 
      * a Number value. 
      * The value of Number.MIN_SAFE_INTEGER is 9007199254740991 2^53 − 1.
      */
    MAX_SAFE_INTEGER: number;

    /** 
      * The value of the smallest integer n such that n and n − 1 are both exactly representable as 
      * a Number value. 
      * The value of Number.MIN_SAFE_INTEGER is −9007199254740991 (−(2^53 − 1)).
      */
    MIN_SAFE_INTEGER: number;

    /**
      * Converts a string to a floating-point number. 
      * @param string A string that contains a floating-point number. 
      */
    parseFloat(string: string): number;

    /**
      * Converts A string to an integer.
      * @param s A string to convert into a number.
      * @param radix A value between 2 and 36 that specifies the base of the number in numString. 
      * If this argument is not supplied, strings with a prefix of '0x' are considered hexadecimal.
      * All other strings are considered decimal.
      */
    parseInt(string: string, radix?: number): number;
}

interface Array<T> {
    /** Iterator */
    [Symbol.iterator](): IterableIterator<T>;

    /**
     * Returns an object whose properties have the value 'true'
     * when they will be absent when used in a 'with' statement.
     */
    [Symbol.unscopables](): {
        copyWithin: boolean;
        entries: boolean;
        fill: boolean;
        find: boolean;
        findIndex: boolean;
        keys: boolean;
        values: boolean;
    };

    /** 
      * Returns an array of key, value pairs for every entry in the array
      */
    entries(): IterableIterator<[number, T]>;

    /** 
      * Returns an list of keys in the array
      */
    keys(): IterableIterator<number>;

    /** 
      * Returns an list of values in the array
      */
    values(): IterableIterator<T>;

    /** 
      * Returns the value of the first element in the array where predicate is true, and undefined 
      * otherwise.
      * @param predicate find calls predicate once for each element of the array, in ascending 
      * order, until it finds one where predicate returns true. If such an element is found, find 
      * immediately returns that element value. Otherwise, find returns undefined.
      * @param thisArg If provided, it will be used as the this value for each invocation of 
      * predicate. If it is not provided, undefined is used instead.
      */
    find(predicate: (value: T, index: number, obj: Array<T>) => boolean, thisArg?: any): T;

    /** 
      * Returns the index of the first element in the array where predicate is true, and undefined 
      * otherwise.
      * @param predicate find calls predicate once for each element of the array, in ascending 
      * order, until it finds one where predicate returns true. If such an element is found, find 
      * immediately returns that element value. Otherwise, find returns undefined.
      * @param thisArg If provided, it will be used as the this value for each invocation of 
      * predicate. If it is not provided, undefined is used instead.
      */
    findIndex(predicate: (value: T) => boolean, thisArg?: any): number;

    /**
      * Returns the this object after filling the section identified by start and end with value
      * @param value value to fill array section with
      * @param start index to start filling the array at. If start is negative, it is treated as 
      * length+start where length is the length of the array. 
      * @param end index to stop filling the array at. If end is negative, it is treated as 
      * length+end.
      */
    fill(value: T, start?: number, end?: number): T[];

    /** 
      * Returns the this object after copying a section of the array identified by start and end
      * to the same array starting at position target
      * @param target If target is negative, it is treated as length+target where length is the 
      * length of the array. 
      * @param start If start is negative, it is treated as length+start. If end is negative, it 
      * is treated as length+end.
      * @param end If not specified, length of the this object is used as its default value. 
      */
    copyWithin(target: number, start: number, end?: number): T[];
}

interface IArguments {
    /** Iterator */
    [Symbol.iterator](): IterableIterator<any>;
}

interface ArrayConstructor {
    /**
      * Creates an array from an array-like object.
      * @param arrayLike An array-like object to convert to an array.
      * @param mapfn A mapping function to call on every element of the array.
      * @param thisArg Value of 'this' used to invoke the mapfn.
      */
    from<T, U>(arrayLike: ArrayLike<T>, mapfn: (v: T, k: number) => U, thisArg?: any): Array<U>;

    /**
      * Creates an array from an iterable object.
      * @param iterable An iterable object to convert to an array.
      * @param mapfn A mapping function to call on every element of the array.
      * @param thisArg Value of 'this' used to invoke the mapfn.
      */
    from<T, U>(iterable: Iterable<T>, mapfn: (v: T, k: number) => U, thisArg?: any): Array<U>;

    /**
      * Creates an array from an array-like object.
      * @param arrayLike An array-like object to convert to an array.
      */
    from<T>(arrayLike: ArrayLike<T>): Array<T>;

    /**
      * Creates an array from an iterable object.
      * @param iterable An iterable object to convert to an array.
      */
    from<T>(iterable: Iterable<T>): Array<T>;

    /**
      * Returns a new array from a set of elements.
      * @param items A set of elements to include in the new array object.
      */
    of<T>(...items: T[]): Array<T>;
}

interface String {
    /** Iterator */
    [Symbol.iterator](): IterableIterator<string>;

    /**
      * Returns a nonnegative integer Number less than 1114112 (0x110000) that is the code point 
      * value of the UTF-16 encoded code point starting at the string element at position pos in 
      * the String resulting from converting this object to a String. 
      * If there is no element at that position, the result is undefined. 
      * If a valid UTF-16 surrogate pair does not begin at pos, the result is the code unit at pos.
      */
    codePointAt(pos: number): number;

    /**
      * Returns true if searchString appears as a substring of the result of converting this 
      * object to a String, at one or more positions that are 
      * greater than or equal to position; otherwise, returns false.
      * @param searchString search string 
      * @param position If position is undefined, 0 is assumed, so as to search all of the String.
      */
    includes(searchString: string, position?: number): boolean;

    /**
      * Returns true if the sequence of elements of searchString converted to a String is the 
      * same as the corresponding elements of this object (converted to a String) starting at 
      * endPosition – length(this). Otherwise returns false.
      */
    endsWith(searchString: string, endPosition?: number): boolean;

    /**
      * Returns the String value result of normalizing the string into the normalization form 
      * named by form as specified in Unicode Standard Annex #15, Unicode Normalization Forms.
      * @param form Applicable values: "NFC", "NFD", "NFKC", or "NFKD", If not specified default
      * is "NFC"
      */
    normalize(form?: string): string;

    /**
      * Returns a String value that is made from count copies appended together. If count is 0, 
      * T is the empty String is returned.
      * @param count number of copies to append
      */
    repeat(count: number): string;

    /**
      * Returns true if the sequence of elements of searchString converted to a String is the 
      * same as the corresponding elements of this object (converted to a String) starting at 
      * position. Otherwise returns false.
      */
    startsWith(searchString: string, position?: number): boolean;

    // Overloads for objects with methods of well-known symbols.

    /**
      * Matches a string an object that supports being matched against, and returns an array containing the results of that search.
      * @param matcher An object that supports being matched against.
      */
    match(matcher: { [Symbol.match](string: string): RegExpMatchArray; }): RegExpMatchArray;

    /**
      * Replaces text in a string, using an object that supports replacement within a string.
      * @param searchValue A object can search for and replace matches within a string.
      * @param replaceValue A string containing the text to replace for every successful match of searchValue in this string.
      */
    replace(searchValue: { [Symbol.replace](string: string, replaceValue: string): string; }, replaceValue: string): string;

    /**
      * Replaces text in a string, using an object that supports replacement within a string.
      * @param searchValue A object can search for and replace matches within a string.
      * @param replacer A function that returns the replacement text.
      */
    replace(searchValue: { [Symbol.replace](string: string, replacer: (substring: string, ...args: any[]) => string): string; }, replacer: (substring: string, ...args: any[]) => string): string;

    /**
      * Finds the first substring match in a regular expression search.
      * @param searcher An object which supports searching within a string.
      */
    search(searcher: { [Symbol.search](string: string): number; }): number;

    /**
      * Split a string into substrings using the specified separator and return them as an array.
      * @param splitter An object that can split a string.
      * @param limit A value used to limit the number of elements returned in the array.
      */
    split(splitter: { [Symbol.split](string: string, limit?: number): string[]; }, limit?: number): string[];

    /**
      * Returns an <a> HTML anchor element and sets the name attribute to the text value
      * @param name
      */
    anchor(name: string): string;

    /** Returns a <big> HTML element */
    big(): string;

    /** Returns a <blink> HTML element */
    blink(): string;

    /** Returns a <b> HTML element */
    bold(): string;

    /** Returns a <tt> HTML element */
    fixed(): string

    /** Returns a <font> HTML element and sets the color attribute value */
    fontcolor(color: string): string

    /** Returns a <font> HTML element and sets the size attribute value */
    fontsize(size: number): string;

    /** Returns a <font> HTML element and sets the size attribute value */
    fontsize(size: string): string;

    /** Returns an <i> HTML element */
    italics(): string;

    /** Returns an <a> HTML element and sets the href attribute value */
    link(url: string): string;

    /** Returns a <small> HTML element */
    small(): string;

    /** Returns a <strike> HTML element */
    strike(): string;

    /** Returns a <sub> HTML element */
    sub(): string;

    /** Returns a <sup> HTML element */
    sup(): string;
}

interface StringConstructor {
    /**
      * Return the String value whose elements are, in order, the elements in the List elements.
      * If length is 0, the empty string is returned.
      */
    fromCodePoint(...codePoints: number[]): string;

    /**
      * String.raw is intended for use as a tag function of a Tagged Template String. When called
      * as such the first argument will be a well formed template call site object and the rest 
      * parameter will contain the substitution values.
      * @param template A well-formed template string call site representation.
      * @param substitutions A set of substitution values.
      */
    raw(template: TemplateStringsArray, ...substitutions: any[]): string;
}

interface IteratorResult<T> {
    done: boolean;
    value?: T;
}

interface Iterator<T> {
    next(value?: any): IteratorResult<T>;
    return?(value?: any): IteratorResult<T>;
    throw?(e?: any): IteratorResult<T>;
}

interface Iterable<T> {
    [Symbol.iterator](): Iterator<T>;
}

interface IterableIterator<T> extends Iterator<T> {
    [Symbol.iterator](): IterableIterator<T>;
}

interface GeneratorFunction extends Function {

}

interface GeneratorFunctionConstructor {
    /**
      * Creates a new Generator function.
      * @param args A list of arguments the function accepts.
      */
    new (...args: string[]): GeneratorFunction;
    (...args: string[]): GeneratorFunction;
    prototype: GeneratorFunction;
}
declare var GeneratorFunction: GeneratorFunctionConstructor;

interface Math {
    /**
      * Returns the number of leading zero bits in the 32-bit binary representation of a number.
      * @param x A numeric expression.
      */
    clz32(x: number): number;

    /**
      * Returns the result of 32-bit multiplication of two numbers.
      * @param x First number
      * @param y Second number
      */
    imul(x: number, y: number): number;

    /**
      * Returns the sign of the x, indicating whether x is positive, negative or zero.
      * @param x The numeric expression to test
      */
    sign(x: number): number;

    /**
      * Returns the base 10 logarithm of a number.
      * @param x A numeric expression.
      */
    log10(x: number): number;

    /**
      * Returns the base 2 logarithm of a number.
      * @param x A numeric expression.
      */
    log2(x: number): number;

    /**
      * Returns the natural logarithm of 1 + x.
      * @param x A numeric expression.
      */
    log1p(x: number): number;

    /**
      * Returns the result of (e^x - 1) of x (e raised to the power of x, where e is the base of 
      * the natural logarithms).
      * @param x A numeric expression.
      */
    expm1(x: number): number;

    /**
      * Returns the hyperbolic cosine of a number.
      * @param x A numeric expression that contains an angle measured in radians.
      */
    cosh(x: number): number;

    /**
      * Returns the hyperbolic sine of a number.
      * @param x A numeric expression that contains an angle measured in radians.
      */
    sinh(x: number): number;

    /**
      * Returns the hyperbolic tangent of a number.
      * @param x A numeric expression that contains an angle measured in radians.
      */
    tanh(x: number): number;

    /**
      * Returns the inverse hyperbolic cosine of a number.
      * @param x A numeric expression that contains an angle measured in radians.
      */
    acosh(x: number): number;

    /**
      * Returns the inverse hyperbolic sine of a number.
      * @param x A numeric expression that contains an angle measured in radians.
      */
    asinh(x: number): number;

    /**
      * Returns the inverse hyperbolic tangent of a number.
      * @param x A numeric expression that contains an angle measured in radians.
      */
    atanh(x: number): number;

    /**
      * Returns the square root of the sum of squares of its arguments.
      * @param values Values to compute the square root for.
      *     If no arguments are passed, the result is +0.
      *     If there is only one argument, the result is the absolute value.
      *     If any argument is +Infinity or -Infinity, the result is +Infinity.
      *     If any argument is NaN, the result is NaN.
      *     If all arguments are either +0 or −0, the result is +0.
      */
    hypot(...values: number[] ): number;

    /**
      * Returns the integral part of the a numeric expression, x, removing any fractional digits.
      * If x is already an integer, the result is x.
      * @param x A numeric expression.
      */
    trunc(x: number): number;

    /**
      * Returns the nearest single precision float representation of a number.
      * @param x A numeric expression.
      */
    fround(x: number): number;

    /**
      * Returns an implementation-dependent approximation to the cube root of number.
      * @param x A numeric expression.
      */
    cbrt(x: number): number;

    [Symbol.toStringTag]: string;
}

interface Date {
    /**
     * Converts a Date object to a string.
     */
    [Symbol.toPrimitive](hint: "default"): string;
    /**
     * Converts a Date object to a string.
     */
    [Symbol.toPrimitive](hint: "string"): string;
    /**
     * Converts a Date object to a number.
     */
    [Symbol.toPrimitive](hint: "number"): number;
    /**
     * Converts a Date object to a string or number.
     *
     * @param hint The strings "number", "string", or "default" to specify what primitive to return.
     *
     * @throws {TypeError} If 'hint' was given something other than "number", "string", or "default".
     * @returns A number if 'hint' was "number", a string if 'hint' was "string" or "default".
     */
    [Symbol.toPrimitive](hint: string): string | number;
}

interface RegExp {
    /**
      * Matches a string with this regular expression, and returns an array containing the results of
      * that search.
      * @param string A string to search within.
      */
    [Symbol.match](string: string): RegExpMatchArray;

    /**
      * Replaces text in a string, using this regular expression.
      * @param string A String object or string literal whose contents matching against
      *               this regular expression will be replaced
      * @param replaceValue A String object or string literal containing the text to replace for every 
      *                     successful match of this regular expression.
      */
    [Symbol.replace](string: string, replaceValue: string): string;

    /**
      * Replaces text in a string, using this regular expression.
      * @param string A String object or string literal whose contents matching against
      *               this regular expression will be replaced
      * @param replacer A function that returns the replacement text.
      */
    [Symbol.replace](string: string, replacer: (substring: string, ...args: any[]) => string): string;

    /**
      * Finds the position beginning first substring match in a regular expression search
      * using this regular expression.
      *
      * @param string The string to search within.
      */
    [Symbol.search](string: string): number;

    /**
      * Returns an array of substrings that were delimited by strings in the original input that
      * match against this regular expression.
      *
      * If the regular expression contains capturing parentheses, then each time this
      * regular expression matches, the results (including any undefined results) of the
      * capturing parentheses are spliced.
      *
      * @param string string value to split
      * @param limit if not undefined, the output array is truncated so that it contains no more
      * than 'limit' elements.
      */
    [Symbol.split](string: string, limit?: number): string[];

    /**
      * Returns a string indicating the flags of the regular expression in question. This field is read-only.
      * The characters in this string are sequenced and concatenated in the following order:
      *
      *    - "g" for global
      *    - "i" for ignoreCase
      *    - "m" for multiline
      *    - "u" for unicode
      *    - "y" for sticky
      *
      * If no flags are set, the value is the empty string.
      */
    flags: string;

    /** 
      * Returns a Boolean value indicating the state of the sticky flag (y) used with a regular 
      * expression. Default is false. Read-only. 
      */
    sticky: boolean;

    /** 
      * Returns a Boolean value indicating the state of the Unicode flag (u) used with a regular 
      * expression. Default is false. Read-only. 
      */
    unicode: boolean;
}

interface RegExpConstructor {
    [Symbol.species](): RegExpConstructor;
}

interface Map<K, V> {
    clear(): void;
    delete(key: K): boolean;
    entries(): IterableIterator<[K, V]>;
    forEach(callbackfn: (value: V, index: K, map: Map<K, V>) => void, thisArg?: any): void;
    get(key: K): V;
    has(key: K): boolean;
    keys(): IterableIterator<K>;
    set(key: K, value?: V): Map<K, V>;
    size: number;
    values(): IterableIterator<V>;
    [Symbol.iterator]():IterableIterator<[K,V]>;
    [Symbol.toStringTag]: string;
}

interface MapConstructor {
    new (): Map<any, any>;
    new <K, V>(): Map<K, V>;
    new <K, V>(iterable: Iterable<[K, V]>): Map<K, V>;
    prototype: Map<any, any>;
}
declare var Map: MapConstructor;

interface WeakMap<K, V> {
    clear(): void;
    delete(key: K): boolean;
    get(key: K): V;
    has(key: K): boolean;
    set(key: K, value?: V): WeakMap<K, V>;
    [Symbol.toStringTag]: string;
}

interface WeakMapConstructor {
    new (): WeakMap<any, any>;
    new <K, V>(): WeakMap<K, V>;
    new <K, V>(iterable: Iterable<[K, V]>): WeakMap<K, V>;
    prototype: WeakMap<any, any>;
}
declare var WeakMap: WeakMapConstructor;

interface Set<T> {
    add(value: T): Set<T>;
    clear(): void;
    delete(value: T): boolean;
    entries(): IterableIterator<[T, T]>;
    forEach(callbackfn: (value: T, index: T, set: Set<T>) => void, thisArg?: any): void;
    has(value: T): boolean;
    keys(): IterableIterator<T>;
    size: number;
    values(): IterableIterator<T>;
    [Symbol.iterator]():IterableIterator<T>;
    [Symbol.toStringTag]: string;
}

interface SetConstructor {
    new (): Set<any>;
    new <T>(): Set<T>;
    new <T>(iterable: Iterable<T>): Set<T>;
    prototype: Set<any>;
}
declare var Set: SetConstructor;

interface WeakSet<T> {
    add(value: T): WeakSet<T>;
    clear(): void;
    delete(value: T): boolean;
    has(value: T): boolean;
    [Symbol.toStringTag]: string;
}

interface WeakSetConstructor {
    new (): WeakSet<any>;
    new <T>(): WeakSet<T>;
    new <T>(iterable: Iterable<T>): WeakSet<T>;
    prototype: WeakSet<any>;
}
declare var WeakSet: WeakSetConstructor;

interface JSON {
    [Symbol.toStringTag]: string;
}

/**
  * Represents a raw buffer of binary data, which is used to store data for the 
  * different typed arrays. ArrayBuffers cannot be read from or written to directly, 
  * but can be passed to a typed array or DataView Object to interpret the raw 
  * buffer as needed. 
  */
interface ArrayBuffer {
    [Symbol.toStringTag]: string;
}

interface DataView {
    [Symbol.toStringTag]: string;
}

/**
  * A typed array of 8-bit integer values. The contents are initialized to 0. If the requested 
  * number of bytes could not be allocated an exception is raised.
  */
interface Int8Array {
    /** 
      * Returns an array of key, value pairs for every entry in the array
      */
    entries(): IterableIterator<[number, number]>;
    /** 
      * Returns an list of keys in the array
      */
    keys(): IterableIterator<number>;
    /** 
      * Returns an list of values in the array
      */
    values(): IterableIterator<number>;
    [Symbol.iterator](): IterableIterator<number>;
}

interface Int8ArrayConstructor {
    new (elements: Iterable<number>): Int8Array;

    /**
      * Creates an array from an array-like or iterable object.
      * @param arrayLike An array-like or iterable object to convert to an array.
      * @param mapfn A mapping function to call on every element of the array.
      * @param thisArg Value of 'this' used to invoke the mapfn.
      */
    from(arrayLike: Iterable<number>, mapfn?: (v: number, k: number) => number, thisArg?: any): Int8Array;
}

/**
  * A typed array of 8-bit unsigned integer values. The contents are initialized to 0. If the 
  * requested number of bytes could not be allocated an exception is raised.
  */
interface Uint8Array {
    /** 
      * Returns an array of key, value pairs for every entry in the array
      */
    entries(): IterableIterator<[number, number]>;
    /** 
      * Returns an list of keys in the array
      */
    keys(): IterableIterator<number>;
    /** 
      * Returns an list of values in the array
      */
    values(): IterableIterator<number>;
    [Symbol.iterator](): IterableIterator<number>;
}

interface Uint8ArrayConstructor {
    new (elements: Iterable<number>): Uint8Array;

    /**
      * Creates an array from an array-like or iterable object.
      * @param arrayLike An array-like or iterable object to convert to an array.
      * @param mapfn A mapping function to call on every element of the array.
      * @param thisArg Value of 'this' used to invoke the mapfn.
      */
    from(arrayLike: Iterable<number>, mapfn?: (v: number, k: number) => number, thisArg?: any): Uint8Array;
}

/**
  * A typed array of 8-bit unsigned integer (clamped) values. The contents are initialized to 0. 
  * If the requested number of bytes could not be allocated an exception is raised.
  */
interface Uint8ClampedArray {
    /** 
      * Returns an array of key, value pairs for every entry in the array
      */
    entries(): IterableIterator<[number, number]>;

    /** 
      * Returns an list of keys in the array
      */
    keys(): IterableIterator<number>;

    /** 
      * Returns an list of values in the array
      */
    values(): IterableIterator<number>;

    [Symbol.iterator](): IterableIterator<number>;
}

interface Uint8ClampedArrayConstructor {
    new (elements: Iterable<number>): Uint8ClampedArray;


    /**
      * Creates an array from an array-like or iterable object.
      * @param arrayLike An array-like or iterable object to convert to an array.
      * @param mapfn A mapping function to call on every element of the array.
      * @param thisArg Value of 'this' used to invoke the mapfn.
      */
    from(arrayLike: Iterable<number>, mapfn?: (v: number, k: number) => number, thisArg?: any): Uint8ClampedArray;
}

/**
  * A typed array of 16-bit signed integer values. The contents are initialized to 0. If the 
  * requested number of bytes could not be allocated an exception is raised.
  */
interface Int16Array {
    /** 
      * Returns an array of key, value pairs for every entry in the array
      */
    entries(): IterableIterator<[number, number]>;

    /** 
      * Returns an list of keys in the array
      */
    keys(): IterableIterator<number>;

    /** 
      * Returns an list of values in the array
      */
    values(): IterableIterator<number>;


    [Symbol.iterator](): IterableIterator<number>;
}

interface Int16ArrayConstructor {
    new (elements: Iterable<number>): Int16Array;

    /**
      * Creates an array from an array-like or iterable object.
      * @param arrayLike An array-like or iterable object to convert to an array.
      * @param mapfn A mapping function to call on every element of the array.
      * @param thisArg Value of 'this' used to invoke the mapfn.
      */
    from(arrayLike: Iterable<number>, mapfn?: (v: number, k: number) => number, thisArg?: any): Int16Array;
}

/**
  * A typed array of 16-bit unsigned integer values. The contents are initialized to 0. If the 
  * requested number of bytes could not be allocated an exception is raised.
  */
interface Uint16Array {
    /** 
      * Returns an array of key, value pairs for every entry in the array
      */
    entries(): IterableIterator<[number, number]>;
    /** 
      * Returns an list of keys in the array
      */
    keys(): IterableIterator<number>;
    /** 
      * Returns an list of values in the array
      */
    values(): IterableIterator<number>;
    [Symbol.iterator](): IterableIterator<number>;
}

interface Uint16ArrayConstructor {
    new (elements: Iterable<number>): Uint16Array;

    /**
      * Creates an array from an array-like or iterable object.
      * @param arrayLike An array-like or iterable object to convert to an array.
      * @param mapfn A mapping function to call on every element of the array.
      * @param thisArg Value of 'this' used to invoke the mapfn.
      */
    from(arrayLike: Iterable<number>, mapfn?: (v: number, k: number) => number, thisArg?: any): Uint16Array;
}

/**
  * A typed array of 32-bit signed integer values. The contents are initialized to 0. If the 
  * requested number of bytes could not be allocated an exception is raised.
  */
interface Int32Array {
    /** 
      * Returns an array of key, value pairs for every entry in the array
      */
    entries(): IterableIterator<[number, number]>;
    /** 
      * Returns an list of keys in the array
      */
    keys(): IterableIterator<number>;
    /** 
      * Returns an list of values in the array
      */
    values(): IterableIterator<number>;
    [Symbol.iterator](): IterableIterator<number>;
}

interface Int32ArrayConstructor {
    new (elements: Iterable<number>): Int32Array;

    /**
      * Creates an array from an array-like or iterable object.
      * @param arrayLike An array-like or iterable object to convert to an array.
      * @param mapfn A mapping function to call on every element of the array.
      * @param thisArg Value of 'this' used to invoke the mapfn.
      */
    from(arrayLike: Iterable<number>, mapfn?: (v: number, k: number) => number, thisArg?: any): Int32Array;
}

/**
  * A typed array of 32-bit unsigned integer values. The contents are initialized to 0. If the 
  * requested number of bytes could not be allocated an exception is raised.
  */
interface Uint32Array {
    /** 
      * Returns an array of key, value pairs for every entry in the array
      */
    entries(): IterableIterator<[number, number]>;
    /** 
      * Returns an list of keys in the array
      */
    keys(): IterableIterator<number>;
    /** 
      * Returns an list of values in the array
      */
    values(): IterableIterator<number>;
    [Symbol.iterator](): IterableIterator<number>;
}

interface Uint32ArrayConstructor {
    new (elements: Iterable<number>): Uint32Array;

    /**
      * Creates an array from an array-like or iterable object.
      * @param arrayLike An array-like or iterable object to convert to an array.
      * @param mapfn A mapping function to call on every element of the array.
      * @param thisArg Value of 'this' used to invoke the mapfn.
      */
    from(arrayLike: Iterable<number>, mapfn?: (v: number, k: number) => number, thisArg?: any): Uint32Array;
}

/**
  * A typed array of 32-bit float values. The contents are initialized to 0. If the requested number
  * of bytes could not be allocated an exception is raised.
  */
interface Float32Array {
    /** 
      * Returns an array of key, value pairs for every entry in the array
      */
    entries(): IterableIterator<[number, number]>;
    /** 
      * Returns an list of keys in the array
      */
    keys(): IterableIterator<number>;
    /** 
      * Returns an list of values in the array
      */
    values(): IterableIterator<number>;
    [Symbol.iterator](): IterableIterator<number>;
}

interface Float32ArrayConstructor {
    new (elements: Iterable<number>): Float32Array;

    /**
      * Creates an array from an array-like or iterable object.
      * @param arrayLike An array-like or iterable object to convert to an array.
      * @param mapfn A mapping function to call on every element of the array.
      * @param thisArg Value of 'this' used to invoke the mapfn.
      */
    from(arrayLike: Iterable<number>, mapfn?: (v: number, k: number) => number, thisArg?: any): Float32Array;
}

/**
  * A typed array of 64-bit float values. The contents are initialized to 0. If the requested 
  * number of bytes could not be allocated an exception is raised.
  */
interface Float64Array {
    /** 
      * Returns an array of key, value pairs for every entry in the array
      */
    entries(): IterableIterator<[number, number]>;
    /** 
      * Returns an list of keys in the array
      */
    keys(): IterableIterator<number>;
    /** 
      * Returns an list of values in the array
      */
    values(): IterableIterator<number>;
    [Symbol.iterator](): IterableIterator<number>;
}

interface Float64ArrayConstructor {
    new (elements: Iterable<number>): Float64Array;

    /**
      * Creates an array from an array-like or iterable object.
      * @param arrayLike An array-like or iterable object to convert to an array.
      * @param mapfn A mapping function to call on every element of the array.
      * @param thisArg Value of 'this' used to invoke the mapfn.
      */
    from(arrayLike: Iterable<number>, mapfn?: (v: number, k: number) => number, thisArg?: any): Float64Array;
}

interface ProxyHandler<T> {
    getPrototypeOf? (target: T): any;
    setPrototypeOf? (target: T, v: any): boolean;
    isExtensible? (target: T): boolean;
    preventExtensions? (target: T): boolean;
    getOwnPropertyDescriptor? (target: T, p: PropertyKey): PropertyDescriptor;
    has? (target: T, p: PropertyKey): boolean;
    get? (target: T, p: PropertyKey, receiver: any): any;
    set? (target: T, p: PropertyKey, value: any, receiver: any): boolean;
    deleteProperty? (target: T, p: PropertyKey): boolean;
    defineProperty? (target: T, p: PropertyKey, attributes: PropertyDescriptor): boolean;
    enumerate? (target: T): PropertyKey[];
    ownKeys? (target: T): PropertyKey[];
    apply? (target: T, thisArg: any, argArray?: any): any;
    construct? (target: T, thisArg: any, argArray?: any): any;
}

interface ProxyConstructor {
    revocable<T>(target: T, handler: ProxyHandler<T>): { proxy: T; revoke: () => void; };
    new <T>(target: T, handler: ProxyHandler<T>): T
}
declare var Proxy: ProxyConstructor;

declare namespace Reflect {
    function apply(target: Function, thisArgument: any, argumentsList: ArrayLike<any>): any;
    function construct(target: Function, argumentsList: ArrayLike<any>, newTarget?: any): any;
    function defineProperty(target: any, propertyKey: PropertyKey, attributes: PropertyDescriptor): boolean;
    function deleteProperty(target: any, propertyKey: PropertyKey): boolean;
    function enumerate(target: any): IterableIterator<any>;
    function get(target: any, propertyKey: PropertyKey, receiver?: any): any;
    function getOwnPropertyDescriptor(target: any, propertyKey: PropertyKey): PropertyDescriptor;
    function getPrototypeOf(target: any): any;
    function has(target: any, propertyKey: string): boolean;
    function has(target: any, propertyKey: symbol): boolean;
    function isExtensible(target: any): boolean;
    function ownKeys(target: any): Array<PropertyKey>;
    function preventExtensions(target: any): boolean;
    function set(target: any, propertyKey: PropertyKey, value: any, receiver? :any): boolean;
    function setPrototypeOf(target: any, proto: any): boolean;
}

/**
 * Represents the completion of an asynchronous operation
 */
interface Promise<T> {
    /**
    * Attaches callbacks for the resolution and/or rejection of the Promise.
    * @param onfulfilled The callback to execute when the Promise is resolved.
    * @param onrejected The callback to execute when the Promise is rejected.
    * @returns A Promise for the completion of which ever callback is executed.
    */
    then<TResult>(onfulfilled?: (value: T) => TResult | PromiseLike<TResult>, onrejected?: (reason: any) => TResult | PromiseLike<TResult>): Promise<TResult>;
    then<TResult>(onfulfilled?: (value: T) => TResult | PromiseLike<TResult>, onrejected?: (reason: any) => void): Promise<TResult>;

    /**
     * Attaches a callback for only the rejection of the Promise.
     * @param onrejected The callback to execute when the Promise is rejected.
     * @returns A Promise for the completion of the callback.
     */
    catch(onrejected?: (reason: any) => T | PromiseLike<T>): Promise<T>;
    catch(onrejected?: (reason: any) => void): Promise<T>;

    [Symbol.toStringTag]: string;
}

interface PromiseConstructor {
    /** 
      * A reference to the prototype. 
      */
    prototype: Promise<any>;

    /**
     * Creates a new Promise.
     * @param executor A callback used to initialize the promise. This callback is passed two arguments: 
     * a resolve callback used resolve the promise with a value or the result of another promise, 
     * and a reject callback used to reject the promise with a provided reason or error.
     */
    new <T>(executor: (resolve: (value?: T | PromiseLike<T>) => void, reject: (reason?: any) => void) => void): Promise<T>;

    /**
     * Creates a Promise that is resolved with an array of results when all of the provided Promises 
     * resolve, or rejected when any Promise is rejected.
     * @param values An array of Promises.
     * @returns A new Promise.
     */
    all<T>(values: Iterable<T | PromiseLike<T>>): Promise<T[]>;

    /**
     * Creates a Promise that is resolved or rejected when any of the provided Promises are resolved 
     * or rejected.
     * @param values An array of Promises.
     * @returns A new Promise.
     */
    race<T>(values: Iterable<T | PromiseLike<T>>): Promise<T>;

    /**
     * Creates a new rejected promise for the provided reason.
     * @param reason The reason the promise was rejected.
     * @returns A new rejected Promise.
     */
    reject(reason: any): Promise<void>;

    /**
     * Creates a new rejected promise for the provided reason.
     * @param reason The reason the promise was rejected.
     * @returns A new rejected Promise.
     */
    reject<T>(reason: any): Promise<T>;

    /**
      * Creates a new resolved promise for the provided value.
      * @param value A promise.
      * @returns A promise whose internal state matches the provided promise.
      */
    resolve<T>(value: T | PromiseLike<T>): Promise<T>;

    /**
     * Creates a new resolved promise .
     * @returns A resolved promise.
     */
    resolve(): Promise<void>;

    [Symbol.species]: Function;
}

declare var Promise: PromiseConstructor;
