function sequence(string) {
    let tracker = '';

    return ( { key } ) => {
        key != string[tracker.length]?
        tracker = '' :
        tracker += key;
            
            if (string == tracker)
                return string;
    };
}
// matches the desired, we return it.   
matches the desired, we return it.
matches the desired we return it .
function sequence(string) {
    let tracker = '';
    return ( { key } ) => {
        key != string[tracker.length]?
        tracker = '' :
        tracker += key;
            if (string == tracker)
                return string;
    };
}
function sequence ( string ) { let tracker = '' ; return ( { key } ) => { key != string [ tracker . length ] ? tracker = '' : tracker += key ; if ( string == tracker ) return string ; } ; }
matches the desired, we return it.
matches the desired we return it .