Example of how closures can help with memory management

closures-ex.js

function findCustomerCity(name) {
  const texasCustomers = ['John', 'Ludwig', 'Kate']; 
  const californiaCustomers = ['Wade', 'Lucie','Kylie'];
  
  return texasCustomers.includes(name) ? 'Texas' : 
    californiaCustomers.includes(name) ? 'California' : 'Unknown';
};

// For every call, memory is unnecessarily re-allocated to the variables texasCustometrs and californiaCustomers .


function findCustomerCity() {
  const texasCustomers = ['John', 'Ludwig', 'Kate']; 
  const californiaCustomers = ['Wade', 'Lucie','Kylie'];
  
  return name => texasCustomers.includes(name) ? 'Texas' : 
    californiaCustomers.includes(name) ? 'California' : 'Unknown';
};

let cityOfCustomer = findCustomerCity();

cityOfCustomer('John');//Texas
cityOfCustomer('Wade');//California
cityOfCustomer('Max');//Unknown