Event and Notification System

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Runtime.Notify Semantics

The System.Runtime.Notify syscall emits a notification event consisting of:

• Event name: A string identifying the event type
• State array: An array of stack items containing the event data

In Solidity, emit statements are compiled to Runtime.Notify calls. The event name corresponds to the Solidity event name, and the indexed/non-indexed parameters are packed into the state array.

// Solidity
emit Transfer(from, to, amount);

// Compiles to NeoVM:
// PUSH3 args onto stack, PACK into array
// PUSHDATA "Transfer"
// SYSCALL System.Runtime.Notify

Runtime.Log

System.Runtime.Log emits a simple string log message. This is used for debugging and does not appear in on-chain event logs.