Date: Tue, 24 Oct 2023 13:05:56 +0000
From: Andrew Poelstra <apoelstra@wpsoftware.net>
To: Rusty Russell <rusty@rustcorp.com.au>
Message-ID: <ZTfBNGipc2O+ojvr@camus>
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Cc: Bitcoin Protocol Discussion <bitcoin-dev@lists.linuxfoundation.org>
Subject: Re: [bitcoin-dev] Proposed BIP for OP_CAT
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On Tue, Oct 24, 2023 at 02:15:49PM +1030, Rusty Russell wrote:
> Andrew Poelstra <apoelstra@wpsoftware.net> writes:
> > I had a similar thought. But my feeling is that replacing the stack
> > interpreter data structure is still too invasive to justify the benefit.
> >
> > Also, one of my favorite things about this BIP is the tiny diff.
>=20
> To be fair, this diff is even smaller than the OP_CAT diff :)
>

Oh, look at that :). For some reason I had it in my head that looping
like this would mess up the asymptotics and meaningfully harm
performance. But no, it just involves adding (at most) 1000 numbers.
Which is unlikely to even be measurable.

> Though I had to strongly resist refactoring, that interpreter code
> needs a good shake!  Using a class for the stack is worth doing anyway
> (macros, really??).
>

Hah, agreed, but it still makes my hands sweat to think about refactoring
that file.

--=20
Andrew Poelstra
Director of Research, Blockstream
Email: apoelstra at wpsoftware.net
Web:   https://www.wpsoftware.net/andrew

The sun is always shining in space
    -Justin Lewis-Webster


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