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For Cadence 0.42 go to Legacy Docs

The FungibleToken contract implements the Fungible Token Standard. It is the second contract ever deployed on Flow.

• Basic Fungible Token Tutorial
• Fungible Token Guide
• Fungible Token Standard Repo

The FungibleTokenMetadataViews and FungibleTokenSwitchboard contracts are also deployed to the same account as FungibleToken.

Source: FungibleToken.cdc

Network	Contract Address
Emulator	0xee82856bf20e2aa6
Cadence Testing Framework	0x0000000000000002
PreviewNet	0xa0225e7000ac82a9
Testnet	0x9a0766d93b6608b7
Mainnet	0xf233dcee88fe0abe

Transactions

All FungibleToken projects are encouraged to use the generic token transactions and scripts in the flow-ft repo. They can be used for any token that implements the fungible token standard properly without changing any code besides import addresses on different networks.

Events

Events emitted from all contracts follow a standard format:

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A.{contract address}.{contract name}.{event name}

The components of the format are:

• contract address - the address of the account the contract has been deployed to
• contract name - the name of the contract in the source code
• event name - the name of the event as declared in the source code

FungibleToken Events

Contracts that implement the Fungible Token standard get access to standard events that are emitted every time a relevant action occurs, like depositing and withdrawing tokens.

This means that projects do not have to implement their own custom events unless the standard events do not satisfy requirements they have for events.

The FungibleToken events will have the following format:

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A.{contract address}.FungibleToken.Deposited

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A.{contract address}.FungibleToken.Withdrawn

Where the contract address is the FungibleToken address on the network being queried. The addresses on the various networks are shown above.

FungibleToken.Deposited

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access(all) event Deposited (

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type: String,

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amount: UFix64,

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to: Address?,

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toUUID: UInt64,

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depositedUUID: UInt64,

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balanceAfter: UFix64

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)

Whenever deposit() is called on a resource type that implements FungibleToken.Vault, the FungibleToken.Deposited event is emitted with the following arguments:

• type: String: The type identifier of the token being deposited.
  • Example: A.4445e7ad11568276.FlowToken.Vault
• amount: UFix64: The amount of tokens that were deposited.
  • Example: 0.00017485
• to: Address?: The address of the account that owns the Vault that received the tokens. If the vault is not stored in an account, to will be nil.
  • Example: 0x4445e7ad11568276
• toUUID: UInt64: The UUID of the Vault that received the tokens.
  • Example: 177021372071991
• depositedUUID: The UUID of the Vault that was deposited (and therefore destroyed).
  • Example: 177021372071991
• balanceAfter: UFix64: The balance of the Vault that received the tokens after the deposit happened.
  • Example: 1.00047545

FungibleToken.Withdrawn

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access(all) event Withdrawn (

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type: String,

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amount: UFix64,

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from: Address?,

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fromUUID: UInt64,

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withdrawnUUID: UInt64,

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balanceAfter: UFix64

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)

Whenever withdraw() is called on a resource type that implements FungibleToken.Vault, the FungibleToken.Withdrawn event is emitted with the following arguments:

• type: String: The type identifier of the token being withdrawn.
  • Example: A.4445e7ad11568276.FlowToken.Vault
• amount: UFix64: The amount of tokens that were withdrawn.
  • Example: 0.00017485
• from: Address?: The address of the account that owns the Vault that the tokens were withdrawn from. If the vault is not stored in an account, to will be nil.
  • Example: 0x4445e7ad11568276
• fromUUID: UInt64: The UUID of the Vault that the tokens were withdrawn from.
  • Example: 177021372071991
• withdrawnUUID: The UUID of the Vault that was withdrawn.
  • Example: 177021372071991
• balanceAfter: UFix64: The balance of the Vault that the tokens were withdrawn from after the withdrawal.
  • Example: 1.00047545

FungibleToken.Burned

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access(all) event Burned (

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type: String,

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amount: UFix64,

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fromUUID: UInt64

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)

Whenever a fungible token that implements FungibleToken.Vault is burned via the Burner.burn() method, this event is emitted with the following arguments:

• type: String: The type identifier of the token that was burnt.
  • Example: A.4445e7ad11568276.FlowToken.Vault
• amount: UFix64: The amount of tokens that were burnt.
  • Example: 0.00017485
• fromUUID: UInt64: The UUID of the Vault that was burnt.
  • Example: 177021372071991