
{{alias}}( x, indicator[, thisArg] )
    Groups element values according to an indicator function.

    When invoked, the indicator function is provided the following arguments:

    - value: current array element.
    - index: current array element index.
    - arr: input array.

    The value returned by an indicator function should be a value which can be
    serialized as an object key.

    If provided an empty array, the function returns an empty object.

    Parameters
    ----------
    x: ArrayLike
        Input array.

    indicator: Function
        Indicator function specifying which group an element in the input array
        belongs to.

    thisArg: any (optional)
        Indicator function execution context.

    Returns
    -------
    out: Object
        Group results.

    Examples
    --------
    > function fcn( v ) { return v[ 0 ]; };
    > var x = [ 'beep', 'boop', 'foo', 'bar' ];
    > var out = {{alias}}( x, fcn )
    { 'b': [ 'beep', 'boop', 'bar' ], 'f': [ 'foo' ] }

    See Also
    --------

