A safe token standard for SIP009 and SIP010 is required for marketplaces to be able to safely (ie without having to use as-contract) call the transfer method of FT/NFT token contracts.
Clarity Lab are proposing a new SIP that complements the existing standards and adds a new function to each.
Details can be found here
Hey @mikecohen.id, thank you for writing this up!
One minor comment that might be helpful:
However safe transfer is still needed as the assets under threat do not belong to the end user and so cannot be guarded by post conditions
Actually, they can! Your post-conditions can apply to any principal (standard or contract), even if it isn’t materialized yet. So, if an exchange had an intermediate contract that called a SIP-009 or SIP-010 transfer on behalf of another user, the exchange’s wallet can set post-conditions on both the user and the intermediate contract as well as itself.
Thanks for this info Jude. I’ll consider the implications and update the document before submitting a Pull Request.