Skip to main content
Version: 3.x


Applied on fields of ink! event types to indicate that they are topics.

Tells the ink! codegen to provide a topic hash for the given field. Every ink! event can only have a limited number of such topic field. The semantics are similar to indexed event arguments in Solidity.


pub struct Transferred {
from: Option<AccountId>,

to: Option<AccountId>,

amount: Balance