stx-transfer-memo?
Transferring STX with a memo field in Clarity smart contracts.
Function Signature
(stx-transfer-memo? amount sender recipient memo)
- Input: 
uint, principal, principal, buff - Output: 
(response bool uint) 
Why it matters
The stx-transfer-memo? function is crucial for:
- 1Transferring STX between principals with an additional memo field.
 - 2Implementing logic that requires recording a memo with each transfer.
 - 3Ensuring data integrity by validating the transfer operation.
 - 4Simplifying the process of handling STX transfers with memos in smart contracts.
 
When to use it
Use stx-transfer-memo? when you need to:
- Transfer STX between principals with an additional memo field.
 - Implement logic that requires recording a memo with each transfer.
 - Validate the transfer operation to ensure data integrity.
 - Handle STX transfers with memos in your smart contract.
 
Best Practices
- Ensure the 
amountis positive and thesenderhas sufficient balance. - Use meaningful variable names for better readability.
 - Combine with other STX functions for comprehensive account management.
 - Handle the possible error cases to ensure robust contract behavior.
 
Practical Example: Transferring STX with a Memo
Let's implement a function that transfers STX with a memo from the tx-sender to a recipient:
(define-public (transfer-stx-with-memo (amount uint) (recipient principal) (memo (buff 34)))(stx-transfer-memo? amount tx-sender recipient memo));; Usage(transfer-stx-with-memo u60 'SZ2J6ZY48GV1EZ5V2V5RB9MP66SW86PYKKQ9H6DPR 0x010203);; Returns (ok true) if successful(transfer-stx-with-memo u50 'SZ2J6ZY48GV1EZ5V2V5RB9MP66SW86PYKKQ9H6DPR 0x040506);; Returns (err u1) if the sender does not have enough balance
This example demonstrates:
- 1Using 
stx-transfer-memo?to transfer STX with a memo. - 2Implementing a public function to handle the STX transfer with a memo.
 - 3Handling both successful and error cases.
 
Common Pitfalls
- 1Using 
stx-transfer-memo?with a non-positive amount, causing the operation to fail. - 2Assuming the transfer operation will always succeed, leading to unhandled error cases.
 - 3Not handling all possible conditions, resulting in incomplete account management.
 - 4Overlooking the need for proper error handling and validation.
 
Related Functions
stx-get-balance: Queries the STX balance of a principal.stx-transfer?: Transfers STX from one principal to another without a memo.stx-burn?: Burns STX from a principal's account.
Conclusion
The stx-transfer-memo? function is a fundamental tool for transferring STX with a memo in Clarity smart contracts. It allows developers to implement logic that requires recording a memo with each transfer, ensuring data integrity and simplifying STX transfer operations. When used effectively, stx-transfer-memo? enhances the reliability and maintainability of your smart contract code by providing a clear and concise way to handle STX transfers with memos.