function iterFill( iterator, value, begin, end ) {
	var iter;
	var FLG;
	var N;
	var M;
	var i;
	if ( !isIteratorLike( iterator ) ) {
		throw new TypeError( format( 'invalid argument. First argument must be an iterator protocol-compliant object. Value: `%s`.', iterator ) );
	}
	if ( arguments.length > 2 ) {
		if ( !isNonNegativeInteger( begin ) ) {
			throw new TypeError( format( 'invalid argument. Third argument must be a nonnegative integer. Value: `%s`.', begin ) );
		}
		N = begin;
		if ( arguments.length > 3 ) {
			if ( !isNonNegativeInteger( end ) ) {
				throw new TypeError( format( 'invalid argument. Fourth argument must be a nonnegative integer. Value: `%s`.', end ) );
			}
			M = end;
		} else {
			M = END;
		}
	} else if ( arguments.length < 2 ) {
		throw new Error( 'insufficient arguments. Must provide both an iterator and a static value.' );
	} else {
		N = BEGIN;
		M = END;
	}
	// Create an iterator protocol-compliant object:
	iter = {};
	setReadOnly( iter, 'next', next );
	setReadOnly( iter, 'return', finish );

	// If an environment supports `Symbol.iterator`, make the iterator iterable:
	if ( iteratorSymbol && isFunction( iterator[ iteratorSymbol ] ) ) {
		setReadOnly( iter, iteratorSymbol, factory );
	}
	i = -1;
	return iter;

	/**
	* Returns an iterator protocol-compliant object containing the next iterated value.
	*
	* @private
	* @returns {Object} iterator protocol-compliant object
	*/
	function next() {
		var v;
		if ( FLG ) {
			return {
				'done': true
			};
		}
		v = iterator.next();
		i += 1;
		if ( v.done ) {
			FLG = true;
			return v;
		}
		return {
			'value': ( i >= N && i < M ) ? value : v.value,
			'done': false
		};
	}

	/**
	* Finishes an iterator.
	*
	* @private
	* @param {*} [value] - value to return
	* @returns {Object} iterator protocol-compliant object
	*/
	function finish( 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 iterFill( iterator[ iteratorSymbol ](), value, N, M );
	}
}
Returns an iterator which replaces all values from a provided iterator from a start index to an end index with a static value.

@param {Iterator} iterator - input iterator
@param {*} value - static value
@param {NonNegativeInteger} [begin=0] - start iteration index (inclusive)
@param {NonNegativeInteger} [end=1e308] - end iteration index (non-inclusive)
@throws {Error} must provide both an iterator and a static value
@throws {TypeError} first argument must be an iterator protocol-compliant object
@throws {TypeError} third argument must be a nonnegative integer
@throws {TypeError} fourth argument must be a nonnegative integer
@returns {Iterator} iterator

@example
var randu = require( '@stdlib/random/iter/randu' );

var iter = iterFill( randu(), 3.14, 0, 2 );

var r = iter.next().value;
// returns 3.14

r = iter.next().value;
// returns 3.14

r = iter.next().value;
// returns <number>

// ...