function thunk( iter ) {
		var args;
		var i;
		if ( !isIteratorLike( iter ) ) {
			throw new TypeError( format( 'invalid argument. Must provide an iterator. Value: `%s`.', iter ) );
		}
		args = [ iter ];
		for ( i = 0; i < nargs; i++ ) {
			args.push( pargs[ i ] );
		}
		return iterFcn.apply( null, args );
	}
Invokes an iterator function with a provided iterator and previously provided iterator function arguments.

@private
@param {Iterator} iter - input iterator
@throws {TypeError} must provide an iterator
@returns {*} iterator function result