Tips for how to retrieve an instance of a class or an error in Typescript

Currently, I am experimenting with TypeScript and a library called TypeORM while constructing custom repositories for my models.

Within my models, specifically the Buyer model, there is a corresponding BuyerRepository featuring a method named createAndSave.

If the goal is for this method to either return a successful Buyer or an Error('some reason') if an issue arises, would it be appropriate to utilize 

throw new Error('buyer already exists')
?

I am aiming for functionality akin to Go's approach: 

res, err := buyerRepo.createAndSave(buyer)

typescript

Answer №1

A common method is to handle errors by throwing and catching them:

try {
   const res = await byuerRepo.createAndSave(...);
   console.log('buyer:' res)
} catch(e) {
  console.log(e)
}

You also have the option of using plain Promises:

byuerRepo.createAndSave(...)
.then(res => { 
   console.log('buyer:' res)
})
.catch(e) {
  console.log(e)
}

If you want a different approach similar to Go:

For those who prefer functional programming, this library might be helpful:

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