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- Create a new SField metadata enum, sMD_NeedsAsset, which indicates the field should be associated with an Asset so it can be rounded. - Add a new STTakesAsset intermediate class to handle the Asset association to a derived ST class. Currently only used in STNumber, but could be used by other types in the future. - Add "associateAsset" which takes an SLE and an Asset, finds the sMD_NeedsAsset fields, and associates the Asset to them. In the case of STNumber, that both stores the Asset, and rounds the value immediately. - Transactors only need to add a call to associateAsset _after_ all of the STNumbers have been set. Unfortunately, the inner workings of STObject do not do the association correctly with uninitialized fields. - When serializing an STNumber that has an Asset, round it before serializing. - Add an override of roundToAsset, which rounds a Number value in place to an Asset, but without any additional scale. - Update and fix a bunch of Loan-related tests to accommodate the expanded Number class. - (Not all tests are fixed yet.)
protocol
Classes and functions for handling data and values associated with the XRP Ledger protocol.
Serialized Objects
Objects transmitted over the network must be serialized into a canonical format. The prefix "ST" refers to classes that deal with the serialized format.
The term "Tx" or "tx" is an abbreviation for "Transaction", a commonly occurring object type.
Optional Fields
Our serialized fields have some "type magic" to make optional fields easier to read:
- The operation
x[sfFoo]means "return the value of 'Foo' if it exists, or the default value if it doesn't." - The operation
x[~sfFoo]means "return the value of 'Foo' if it exists, or nothing if it doesn't." This usage of the tilde/bitwise NOT operator is not standard outside of therippledcodebase.- As a consequence of this,
x[~sfFoo] = y[~sfFoo]assigns the value of Foo from y to x, including omitting Foo from x if it doesn't exist in y.
- As a consequence of this,
Typically, for things that are guaranteed to exist, you use
x[sfFoo] and avoid having to deal with a container that may
or may not hold a value. For things not guaranteed to exist,
you use x[~sfFoo] because you want such a container. It
avoids having to look something up twice, once just to see if
it exists and a second time to get/set its value.
(Real example)
The source of this "type magic" is in SField.h.