Payment Object

A Payment holds digital assets that are in transit or expected to soon be in transit. It can be deposited in Purses, split into or combined with multiple Payments, or claimed (i.e., getting an exclusive Payment and revoking access from anyone else).

Digital assets in Payments can be any of:

• Currency-like, such as our imaginary Quatloos currency.
• Goods-like digital assets, such as theater tickets or magic weapons used in a game.
• Other kinds of rights, such as the right to participate in a particular contract.

A Payment is linear, meaning either a Payment has its full original balance, or it is used up entirely. You cannot partially use a Payment. In other words, if a Payment is 10 Quatloos, you can't take out, say, only 3 Quatloos from it.

However, you can split a Payment into multiple Payments. For example, you could split a 10 Quatloos Payment into two new Payments of 3 Quatloos and 7 Quatloos by calling the anIssuer.split() method which consumes the original 10 Quatloos Payment and creates two new smaller Payments.

Payments are often received from other actors. Since they are not self-verifying, you cannot trust Payments. To get the verified balance of a Payment, call the anIssuer.getAmountOf() method.

To convert a Payment into a new Purse:

1. Get the Payment's trusted Issuer.
2. Use the Issuer to create an empty Purse.
3. Deposit the Payment into the new Purse.

aPurse.deposit() consumes the Payment, making it unavailable for later use.

aPayment.getAllegedBrand()

• Returns: Brand

Returns the Brand indicating the kind of digital asset this Payment purports to be. Because Payments are not trusted, any method calls on them should be treated with suspicion and verified elsewhere. Any successful operation by an Issuer on a Payment verifies it.

const payment = quatloosMint.mintPayment(AmountMath.make(quatloosBrand, 10n));
// Should return 'quatloos'
const allegedBrand = payment.getAllegedBrand();

Related Methods

The following methods on other ERTP components either operate on or return a Payment.

• anIssuer.burn()
  • Destroys all of the digital assets in the Payment.
• anIssuer.getAmountOf()
  • Describes the Payment's balance as an Amount.
• anIssuer.isLive()
  • Returns true if the Payment was created by the Issuer and is available for use (i.e., has not been consumed or burned).
• aMint.mintPayment()
  • Create new digital assets of the Mint's associated Brand.
• aPurse.deposit()
  • Deposits all the contents of payment into the Purse.
• aPurse.getDepositFacet()
  • Creates and returns a new deposit-only facet of the Purse that allows arbitrary other parties to deposit Payments into the Purse.
• aPurse.withdraw()
  • Withdraws the amount of specified digital assets from Purse into a new Payment.

DEPRECATED

• anIssuer.split()
  • Splits a single Payment into two new Payments.
• anIssuer.splitMany()
  • Split a single Payment into multiple Payments.
• anIssuer.claim()
  • Transfers all digital assets from payment to a new Payment.
• anIssuer.combine()
  • Combines multiple Payments into one new Payment.