Being able to differentiate behavior of coin A to another coin B ("coin" being a unit of any so-called programmable currency such as bitcoin, but this proposition is not bitcoin-specific), in a persistent way, means coins A and B have different utility, are no longer functionally interchangeable, and therefore are worth different things to different users. This breaks fungibility.
Alternatively, if programming is not persistent across transactions, it has no memory (apart from the most rudimentary unique identity, such as a serial number) and thus is not "programmable" but "able to be tracked by something else". This makes the coin no different than any current electronic payment system where external, programmable scaffolding (in the form of off-ledger memory and logic) is used to track, route, and generally superimpose conditional behavior onto the currency.
Are fungible currency and programmable currency mutually exclusive concepts?
Alternatively, if programming is not persistent across transactions, it has no memory (apart from the most rudimentary unique identity, such as a serial number) and thus is not "programmable" but "able to be tracked by something else". This makes the coin no different than any current electronic payment system where external, programmable scaffolding (in the form of off-ledger memory and logic) is used to track, route, and generally superimpose conditional behavior onto the currency.
Are fungible currency and programmable currency mutually exclusive concepts?
Indeed, it is annoying, but necessary for the blockchain to be transparent. The best we can do is mixing coins. It's a really annoying process tho. Why don't they add an official mixing feature on the wallet?
