The AddressErrors dictionary is used by the Payment Request API
to report validation errors in a physical address (typically
billing address or a shipping address).

The BasicCardRequest dictionary is a JavaScript object-structure
can be used in the Payment Request API. The properties of BasicCardRequest
defined in the Basic Card Payment spec).

The BasicCardResponse dictionary (related to the Payment Request
although defined in the Basic Card Payment spec) defines an object
for payment response details such as the number/expiry date of
card used to make the payment, and the billing address.

web.payments interfaces.

The MerchantValidationEvent interface of the the Payment Request
enables a merchant to verify themselves as allowed to use a particular
handler.

The PayerErrors dictionary is used by the Payment Request API
indicate the presence of—and to explain how to correct—validation
in the payer details.

The PaymentAddress interface of the Payment Request API is used
store shipping or payment address information.

The PaymentCurrencyAmount dictionary describes an amount of money
terms of both a number of units and the currency (US dollars,
yen, etc.), and is part of the Payment Request API.

The PaymentDetailsBase dictionary is a mixin used by the `PaymentDetailsInit`
`web.payments.PaymentDetailsUpdate` dictionaries.

The PaymentDetailsUpdate dictionary is used to provide updated
to the payment user interface after it has been instantiated.

The `web.payments.PaymentItem` dictionary is used by the Payment
API to describe a single line item on a payment request.

The PaymentMethodChangeEvent interface of the Payment Request
describes the paymentmethodchange event which is fired by some
handlers when the user switches payment instruments (e.g., a
selects a \"store\" card to make a purchase while using Apple

The Payment Request API's PaymentRequest interface the primary
point into the API, and lets web content and apps accept payments
the end user on behalf of the operator of the site or the publisher
the app.

PaymentRequest Events.

The PaymentRequestEvent interface of the the Payment Request
is the object passed to a payment handler when a `web.payments.PaymentRequest`
made.

The PaymentRequestUpdateEvent interface is used for events sent
a `web.payments.PaymentRequest` instance when changes are made
shipping-related information for a pending `web.payments.PaymentRequest`.
events are:

The PaymentResponse interface of the Payment Request API is returned
a user selects a payment method and approves a payment request.

PaymentResponse Events.

The PaymentValidationErrors dictionary represents objects providing
about any and all errors that occurred while processing a payment
When validation of the `web.payments.PaymentResponse` returned
the `PaymentRequest.show()` or `PaymentResponse.retry()` methods
your code creates a PaymentValidationErrors object to pass into
so that the user agent knows what needs to be fixed and what
any error messages to display to the user.