stx-transfer-memo?

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:

1. Transferring STX between principals with an additional memo field.
2. Implementing logic that requires recording a memo with each transfer.
3. Ensuring data integrity by validating the transfer operation.
4. Simplifying 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 amount is positive and the sender has 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:

1. Using stx-transfer-memo? to transfer STX with a memo.
2. Implementing a public function to handle the STX transfer with a memo.
3. Handling both successful and error cases.

Common Pitfalls

1. Using stx-transfer-memo? with a non-positive amount, causing the operation to fail.
2. Assuming the transfer operation will always succeed, leading to unhandled error cases.
3. Not handling all possible conditions, resulting in incomplete account management.
4. Overlooking 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.