JAVASCRIPT

Expected an assignment or function call and instead saw an expression

var fn = client =>  { console.log(client) } ;
fn('cliente 1'); // asignando la referencia de la funcion para ejecutarla

(client => { console.log(client) })('cliente 3'); // auto eejecutando la funcion
 EjecutarEsconder resultados

Expected an assignment or function call and instead saw an expression

post.catogery;

expected an assignment or function call and instead saw an expression

const def = (props) => { <div></div> };
const def = (props) => { return (<div></div>); }; OR const def = (props) => <div></div>;
There are extreme differences between () and {}. Make sure you don't make any.