# Fixed-Term Teller The Fixed Term Teller is an implementation of the Bond Base Teller contract specific to handling user bond transactions and tokenizing bond markets where purchases vest in a fixed amount of time (rounded to the day) as ERC1155 tokens.It implements the functions required by the [Fixed-Term Teller Interface](/smart-contracts/bond-system/teller/teller-interfaces.md#fixed-term-teller-interface) and the [Base Teller](/smart-contracts/bond-system/teller/base-teller.md) Abstract Contract. It also inherits the ERC1155 standard and is itself the contract which provides information on the Bond Tokens it issues. Specifically, it implements the `_handlePayout` function to mint ERC1155 tokens to the user to represent their bond position during a purchase. Additionally, it implements the `deploy` (*i.e. stores the metadata for a new ERC1155 token if one does not exist for a combination of underlying token and the maturity date*), `create` (*allows anyone to mint ERC1155 Bond Tokens for a combination of an underlying token and maturity date by paying a fee to the protocol*), and `redeem` (*redeems ERC1155 Bond Tokens that have vested for the underlying token*). By design, the tokenization of the Teller is not permissioned. This allows other market participants to use the same Bond Tokens that Bond Protocol is issuing to create a standard in the market and drive additional liquidity (*less likely for ERC1155, but it is an option*). ## Methods This section only includes methods not inherited from [Base Teller](/smart-contracts/bond-system/teller/base-teller.md) or [ERC1155](https://github.com/transmissions11/solmate/blob/bff24e835192470ed38bf15dbed6084c2d723ace/src/tokens/ERC1155.sol). ### batchRedeem ```solidity function batchRedeem(uint256[] tokenIds_, uint256[] amounts_) external nonpayable ``` Redeem multiple fixed-term bond tokens for the underlying tokens (bond tokens must have matured) #### Parameters | Name | Type | Description | | ---------- | ---------- | ----------------------------------------- | | tokenIds\_ | uint256\[] | Array of bond token ids | | amounts\_ | uint256\[] | Array of amounts of bond tokens to redeem | ### create ```solidity function create(contract ERC20 underlying_, uint48 expiry_, uint256 amount_) external nonpayable returns (uint256, uint256) ``` Deposit an ERC20 token and mint a future-dated ERC1155 bond token #### Parameters | Name | Type | Description | | ------------ | -------------- | -------------------------------------------------------------------------- | | underlying\_ | contract ERC20 | ERC20 token redeemable when the bond token vests | | expiry\_ | uint48 | Timestamp at which the bond token can be redeemed for the underlying token | | amount\_ | uint256 | Amount of underlying tokens to deposit | #### Returns | Name | Type | Description | | --------- | ------- | ----------------------------------------- | | tokenId | uint256 | ID of the ERC1155 bond token received | | amountOut | uint256 | Amount of the ERC1155 bond token received | ### createFeeDiscount ```solidity function createFeeDiscount() external view returns (uint48) ``` 'Create' function fee discount. Amount standard fee is reduced by for partners who just want to use the 'create' function to issue bond tokens. Configurable by policy. #### Returns | Name | Type | Description | | ----------- | ------ | ----------- | | feeDiscount | uint48 | undefined | ### deploy ```solidity function deploy(contract ERC20 underlying_, uint48 expiry_) external nonpayable returns (uint256) ``` "Deploy" a new ERC1155 bond token for an (underlying, expiry) pair and return its ID. #### Parameters | Name | Type | Description | | ------------ | -------------- | -------------------------------------------------------------------------- | | underlying\_ | contract ERC20 | ERC20 token redeemable when the bond token vests | | expiry\_ | uint48 | Timestamp at which the bond token can be redeemed for the underlying token | #### Returns | Name | Type | Description | | ------- | ------- | ------------------------------------------ | | tokenId | uint256 | ID of the ERC1155 bond token being created | ### getTokenId ```solidity function getTokenId(contract ERC20 underlying_, uint48 expiry_) external pure returns (uint256) ``` Get token ID from token and expiry #### Parameters | Name | Type | Description | | ------------ | -------------- | ------------------------------- | | underlying\_ | contract ERC20 | Address of the underlying token | | expiry\_ | uint48 | Expiry of the bond | #### Returns | Name | Type | Description | | ------- | ------- | -------------------- | | tokenId | uint256 | ID of the bond token | ### getTokenNameAndSymbol ```solidity function getTokenNameAndSymbol(uint256 tokenId_) external view returns (string, string) ``` Get the token name and symbol for a bond token #### Parameters | Name | Type | Description | | --------- | ------- | -------------------- | | tokenId\_ | uint256 | ID of the bond token | #### Returns | Name | Type | Description | | ------ | ------ | ----------------- | | name | string | Bond token name | | symbol | string | Bond token symbol | ### redeem ```solidity function redeem(uint256 tokenId_, uint256 amount_) external nonpayable ``` Redeem a fixed-term bond token for the underlying token (bond token must have matured) #### Parameters | Name | Type | Description | | --------- | ------- | ------------------------------ | | tokenId\_ | uint256 | ID of the bond token to redeem | | amount\_ | uint256 | Amount of bond token to redeem | ### tokenMetadata ```solidity function tokenMetadata(uint256) external view returns (bool active, contract ERC20 payoutToken, uint48 expiry, uint256 supply) ``` #### Parameters | Name | Type | Description | | --------- | ------- | -------------------- | | tokenId\_ | uint256 | ID of the bond token | #### Returns | Name | Type | Description | | ----------- | -------------- | ----------------------------------------------------------------------- | | active | bool | Whether the bond token has been created | | payoutToken | contract ERC20 | Address of the underlying token | | expiry | uint48 | Timestamp when the bond token can be exchanged for the underlying token | | supply | uint256 | Total supply of the bond token | ## Events ### ERC1155BondTokenCreated ```solidity event ERC1155BondTokenCreated(uint256 tokenId, contract ERC20 indexed payoutToken, uint48 indexed expiry) ``` #### Parameters | Name | Type | Description | | --------------------- | -------------- | ---------------------------------------------------------------------- | | tokenId | uint256 | ID of the ERC1155 bond token | | payoutToken `indexed` | contract ERC20 | Address of the underlying token | | expiry `indexed` | uint48 | Timestamp when the bond token can be redeemed for the underlying token | --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. 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