Hey all,

I'm working on the UTXO database for my Python implementation of bitcoind and have found a situation I did not realize was valid, but since it seems to be, had a quick question.

If you look at block #546 the 4th transaction's first input uses its own block's 3rd transaction as an input.
https://blockchain.info/block/000000005a4ded781e667e06ceefafb71410b511fe0d5adc3e5a27ecbec34ae6

My question is, would the other way be valid, that is, could the 3rd transaction of a block, use the 4th transaction from the same block as an input? Or are transactions processed strictly top to bottom?

Thanks,
RicMoo

P.S. If it is valid, another question; what would happen if a transaction was self-referencing? I realize it would be very difficult to find one, but if I could find a transaction X whose input was X and had an output Y, would Y be a new valid utxo, without being a generation transaction input?

.·´¯`·.¸¸.·´¯`·.¸¸.·´¯`·.¸¸.·´¯`·.¸¸.·´¯`·.¸><(((º>

Richard Moore ~ Founder
Genetic Mistakes Software inc.
phone: (778) 882-6125
email: ricmoo@geneticmistakes.com
www: http://GeneticMistakes.com