function iterStridedBy( iterator, fcn, offset, eager, thisArg ) {
	var stride;
	var iter;
	var bool;
	var FLG;
	var idx;
	var ctx;
	var ret;
	var o;
	var v;
	var i;
	var s;
	if ( !isIteratorLike( iterator ) ) {
		throw new TypeError( format( 'invalid argument. First argument must be an iterator protocol-compliant object. Value: `%s`.', iterator ) );
	}
	if ( !isFunction( fcn ) ) {
		throw new TypeError( format( 'invalid argument. Second argument must be a function. Value: `%s`.', fcn ) );
	}
	if ( arguments.length === 3 ) {
		if ( isNonNegativeInteger( offset ) ) {
			idx = offset;
		} else {
			idx = DEFAULT_OFFSET;
			ctx = offset;
		}
		bool = DEFAULT_EAGER;
	} else if ( arguments.length === 4 ) {
		if ( !isNonNegativeInteger( offset ) ) {
			throw new TypeError( format( 'invalid argument. Third argument must be a nonnegative integer. Value: `%s`.', offset ) );
		}
		idx = offset;
		if ( isBoolean( eager ) ) {
			bool = eager;
		} else {
			bool = DEFAULT_EAGER;
			ctx = eager;
		}
	} else if ( arguments.length > 4 ) {
		if ( !isNonNegativeInteger( offset ) ) {
			throw new TypeError( format( 'invalid argument. Third argument must be a nonnegative integer. Value: `%s`.', offset ) );
		}
		idx = offset;
		if ( !isBoolean( eager ) ) {
			throw new TypeError( format( 'invalid argument. Fourth argument must be a boolean. Value: `%s`.', eager ) );
		}
		bool = eager;
		ctx = thisArg;
	} else {
		idx = DEFAULT_OFFSET;
		bool = DEFAULT_EAGER;
	}
	if ( bool ) {
		for ( i = 0; i < idx; i++ ) {
			v = iterator.next();
			if ( v.done ) {
				FLG = true;
				ret = v;
				break;
			}
		}
		// NOTE: if we've successfully advanced the input iterator, `i` is currently equal to `idx` (i.e., the offset)
		i -= 1;
	} else {
		i = -1;
	}
	s = -1;
	stride = 0;

	// Create an iterator protocol-compliant object:
	iter = {};
	setReadOnly( iter, 'next', next );
	setReadOnly( iter, 'return', end );

	// If an environment supports `Symbol.iterator` and the provided iterator is iterable, make the iterator iterable:
	if ( iteratorSymbol && isFunction( iterator[ iteratorSymbol ] ) ) {
		o = idx;
		setReadOnly( iter, iteratorSymbol, factory );
	}
	return iter;

	/**
	* Returns an iterator protocol-compliant object containing the next iterated value.
	*
	* @private
	* @throws {TypeError} callback function must return a positive integer
	* @returns {Object} iterator protocol-compliant object
	*/
	function next() {
		var v;
		if ( FLG ) {
			if ( ret ) {
				v = ret;
				ret = null;
				return v;
			}
			return {
				'done': true
			};
		}
		i += 1;
		while ( i < idx ) {
			v = iterator.next();
			if ( v.done ) {
				FLG = true;
				return {
					'done': true
				};
			}
			i += 1;
		}
		v = iterator.next();
		if ( v.done ) {
			FLG = true;
			return v;
		}
		s += 1;
		stride = fcn.call( ctx, v.value, i, s, stride );
		if ( !isPositiveInteger( stride ) ) {
			throw new TypeError( format( 'invalid return value. Callback function must return a positive integer. Value: `%s`.', stride ) );
		}
		idx += stride;
		return v;
	}

	/**
	* Finishes an iterator.
	*
	* @private
	* @param {*} [value] - value to return
	* @returns {Object} iterator protocol-compliant object
	*/
	function end( value ) {
		FLG = true;
		if ( arguments.length ) {
			return {
				'value': value,
				'done': true
			};
		}
		return {
			'done': true
		};
	}

	/**
	* Returns a new iterator.
	*
	* @private
	* @returns {Iterator} iterator
	*/
	function factory() {
		return iterStridedBy( iterator[ iteratorSymbol ](), fcn, o, bool, ctx );
	}
}
Returns an iterator which steps according to a provided callback function.

@param {Iterator} iterator - input iterator
@param {Function} fcn - stride function
@param {NonNegativeInteger} [offset=0] - offset
@param {boolean} [eager=false] - boolean indicating whether to eagerly advance the input iterator when provided a non-zero offset
@param {*} [thisArg] - stride function execution context
@throws {TypeError} first argument must be an iterator protocol-compliant object
@throws {TypeError} second argument must be a function
@throws {TypeError} third argument must be a nonnegative integer
@throws {TypeError} fourth argument must be a boolean
@returns {Iterator} iterator

@example
var array2iterator = require( '@stdlib/array/to-iterator' );

var arr = array2iterator( [ 0, 1, 2, 3, 4, 5, 6, 7 ] );

function stride( v, i ) {
    return (i % 10)+1;
}

var iter = iterStridedBy( arr, stride );

var r = iter.next().value;
// returns 0

r = iter.next().value;
// returns 1

r = iter.next().value;
// returns 3

// ...