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Date: Sun, 13 Jul 2014 19:25:51 -0700
Message-ID: <CACq0ZD6Mo0uVMM8HU3VrYORQgme7z084B45Cap8GYVwi-xs6vA@mail.gmail.com>
From: Aaron Voisine <voisine@gmail.com>
To: Richard Moore <me@ricmoo.com>
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Cc: Bitcoin Dev <bitcoin-development@lists.sourceforge.net>
Subject: Re: [Bitcoin-development] Self-dependency transaction question...
Precedence: list

I believe tx have to be ordered sequentially within a block. Also
since a tx is referenced by it's hash, it's practically impossible to
make a self referential tx.

Aaron Voisine
breadwallet.com


On Sun, Jul 13, 2014 at 4:32 PM, Richard Moore <me@ricmoo.com> wrote:
> 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 seem=
s
> 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/000000005a4ded781e667e06ceefafb71410b511fe0=
d5adc3e5a27ecbec34ae6
>
> 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, b=
ut
> if I could find a transaction X whose input was X and had an output Y, wo=
uld
> Y be a new valid utxo, without being a generation transaction input?
>
> .=C2=B7=C2=B4=C2=AF`=C2=B7.=C2=B8=C2=B8.=C2=B7=C2=B4=C2=AF`=C2=B7.=C2=B8=
=C2=B8.=C2=B7=C2=B4=C2=AF`=C2=B7.=C2=B8=C2=B8.=C2=B7=C2=B4=C2=AF`=C2=B7.=C2=
=B8=C2=B8.=C2=B7=C2=B4=C2=AF`=C2=B7.=C2=B8><(((=C2=BA>
>
> Richard Moore ~ Founder
> Genetic Mistakes Software inc.
> phone: (778) 882-6125
> email: ricmoo@geneticmistakes.com
> www: http://GeneticMistakes.com
>
>
> -------------------------------------------------------------------------=
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