Event signature · Stablecoins and issued tokens

SupplyDecreased (Paxos) event signature and topic0

The topic0 of the SupplyDecreased (Paxos) event is 0x1b7e18241beced0d7f41fbab1ea8ed468732edbcb74ec4420151654ca71c8a63, the keccak-256 hash of SupplyDecreased(address,uint256); 1 of its 2 arguments is indexed. Tokens burned by the issuer (Paxos).

Anatomy of a SupplyDecreased (Paxos) log

Topics

  • topic00x1b7e18241beced0d7f41fbab1ea8ed468732edbcb74ec4420151654ca71c8a63keccak256("SupplyDecreased(address,uint256)")
  • topic1from (address)indexed: filterable

Data

  • datavalue (uint256)ABI-encoded, decoded with the ABI
Parameters

Arguments and where they sit in the log

Indexed arguments travel as topics and can be filtered cheaply; the others are ABI-encoded together in the data.

NameTypeIn the log
fromaddresstopic1
valueuint256data

Solidity declaration

event SupplyDecreased(address indexed from, uint256 value);

Canonical signature

SupplyDecreased(address,uint256)

topic0

0x1b7e18241beced0d7f41fbab1ea8ed468732edbcb74ec4420151654ca71c8a63

Ready-made alerts

Get an alert on SupplyDecreased

Each rule opens with the contract and the conditions filled in. Sign in, pick your chat and click Create.

Who emits it

Contracts we list that emit SupplyDecreased

Any other contract with the same signature emits a log with the same topic0.

Code

Read SupplyDecreased logs in code

The same filter in viem, ethers and plain JSON-RPC, and the Solidity that emits it. The address is Paxos Gold (PAXG), a contract we list that emits it.

viem
import { createPublicClient, http, parseAbiItem } from "viem"
import { mainnet } from "viem/chains"

const client = createPublicClient({ chain: mainnet, transport: http() })

const logs = await client.getLogs({
  address: "0x45804880de22913dafe09f4980848ece6ecbaf78",
  event: parseAbiItem("event SupplyDecreased(address indexed from, uint256 value)"),
  fromBlock: "latest",
})

for (const log of logs) console.log(log.args) // { from, value }
ethers v6
import { Interface, JsonRpcProvider } from "ethers"

const provider = new JsonRpcProvider(process.env.RPC_URL)
const iface = new Interface(["event SupplyDecreased(address indexed from, uint256 value)"])

const logs = await provider.getLogs({
  address: "0x45804880de22913dafe09f4980848ece6ecbaf78",
  topics: [iface.getEvent("SupplyDecreased")!.topicHash],
})

for (const log of logs) console.log(iface.parseLog(log)?.args)
JSON-RPC (eth_getLogs)
{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "eth_getLogs",
  "params": [
    {
      "address": "0x45804880de22913dafe09f4980848ece6ecbaf78",
      "topics": [
        "0x1b7e18241beced0d7f41fbab1ea8ed468732edbcb74ec4420151654ca71c8a63"
      ],
      "fromBlock": "latest"
    }
  ]
}
Solidity
event SupplyDecreased(address indexed from, uint256 value);

// inside a function:
emit SupplyDecreased(from, value);
Example

An example SupplyDecreased log, encoded and decoded

Placeholder values, not a real transaction: how each argument is stored in the topics and the data, and what decoding gives back.

Encoded (as the node returns it)
  • topic0keccak256("SupplyDecreased(address,uint256)")0x1b7e18241beced0d7f41fbab1ea8ed468732edbcb74ec4420151654ca71c8a63
  • topic1from0x0000000000000000000000001111111111111111111111111111111111111111
  • data0x00000000000000000000000000000000000000000000000000000000000007d0
Decoded with the ABI
  • fromaddress · indexed0x1111111111111111111111111111111111111111
  • valueuint2562000
FAQ

Frequently asked questions

What is the topic0 of the SupplyDecreased (Paxos) event?

0x1b7e18241beced0d7f41fbab1ea8ed468732edbcb74ec4420151654ca71c8a63: the keccak-256 hash of SupplyDecreased(address,uint256).

Which SupplyDecreased (Paxos) arguments are indexed?

from is indexed and sit in the log's topics; value is in the data.

How do I get an alert when a contract emits SupplyDecreased (Paxos)?

Open one of the ready-made rules on this page, or add any contract and pick SupplyDecreased (Paxos) from the event list. Conditions can be set on indexed and non-indexed arguments, and each alert names the contract and links to the transaction.

Keep exploring

More event signatures and tools

Know the moment a contract emits it

The Beta plan is free: one wallet and one contract, no credit card.