In newer versions of typescript you can use:
type Customers = Record<string, Customer>
In older versions you can use:
var map: { [email: string]: Customer; } = { };
map['[email protected]'] = new Customer(); // OK
map[14] = new Customer(); // Not OK, 14 is not a string
map['[email protected]'] = 'x'; // Not OK, 'x' is not a customer
You can also make an interface if you don’t want to type that whole type annotation out every time:
interface StringToCustomerMap {
[email: string]: Customer;
}
var map: StringToCustomerMap = { };
// Equivalent to first line of above