single-io.js

const makeSingleIO = () => {                        
  let put, err;                                     
  const promise = new Promise((resolve, reject) => {
    put = resolve;                                  
    err = reject;                                   
  });                                               
  return { put, err, get: () => promise };           
};                                                  
                                                    
const testSingleIO = async () => {                  
  const testIO = makeSingleIO();                   
  testIO.put("flub");                               
  const result = await testIO.get();                
  console.log(result);                              
};                                                  
                                                    
testSingleIO();