const client = new ApolloClient({ //...
//you forgot to put (new in front of ApolloClent)
//=====================> here is my provide
import ApolloClient from 'apollo-client';
import { InMemoryCache } from 'apollo-cache-inmemory';
import { createHttpLink } from 'apollo-link-http';
const httpLink = createHttpLink({
url: 'http://localhost:4000'
});
export const client = new ApolloClient({
link: httpLink,
cache: new InMemoryCache()
});