📅 Original date posted:2011-12-30
🗒️ Summary of this message: Bitcoin's scripting language has limited ability to manipulate scripts on the stack, but could gain more abilities if certain operations are restored.
📝 Original message:On Sat, 31 Dec 2011, Chris Double wrote:
> On Fri, Dec 30, 2011 at 5:42 AM, <roconnor at theorem.ca> wrote:
>> Basically OP_DUP lets you duplicate the code on the stack and that is the
>> key to looping. I'm pretty sure from here we get get Turing completeness.
>> Using the stack operations I expect you can implement the SK-calculus
>> given an OP_EVAL that allows arbitrary depth.
>>
>> OP_EVAL adds dangerously expressive power to the scripting language.
>
> If you look at the archives of the concatenative programming mailing
> list [1] you'll see lots of examples of people creating stack
> languages with minimal operations that exploit similar functionality
> to reduce the required built in operations. The discussion on the list
> is mostly about stack based languages where programs can be pushed on
> the stack and executed (eg. Joy [2]/Factor/Some Forths).
>
> I don't think the scripting engine in bitcoin has the ability to
> concatenate, append or otherwise manipulate scripts on the stack to be
> eval'd though does it?
It will limited ability manipulate scripts on the stack through the use of
arithmetic and hashing operations, and if OP_CAT, OP_SUBSTR and friends
are ever restored, it will have even more abilities.
--
Russell O'Connor <http://r6.ca/>;
``All talk about `theft,''' the general counsel of the American Graphophone
Company wrote, ``is the merest claptrap, for there exists no property in
ideas musical, literary or artistic, except as defined by statute.''
roconnor at theorem.ca [ARCHIVE] /
npub1a3…zue3f
2023-06-07 02:53:15
in reply to nevent1q…x7qc
Author Public Key
npub1a39ym06slzfdspsuxq2jqcf2u8cddq6sml6w8c28ql28gxw42grqlzue3fPublished at
2023-06-07 02:53:15Event JSON
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"created_at": 1686106395,
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"content": "📅 Original date posted:2011-12-30\n🗒️ Summary of this message: Bitcoin's scripting language has limited ability to manipulate scripts on the stack, but could gain more abilities if certain operations are restored.\n📝 Original message:On Sat, 31 Dec 2011, Chris Double wrote:\n\n\u003e On Fri, Dec 30, 2011 at 5:42 AM, \u003croconnor at theorem.ca\u003e wrote:\n\u003e\u003e Basically OP_DUP lets you duplicate the code on the stack and that is the\n\u003e\u003e key to looping. I'm pretty sure from here we get get Turing completeness.\n\u003e\u003e Using the stack operations I expect you can implement the SK-calculus\n\u003e\u003e given an OP_EVAL that allows arbitrary depth.\n\u003e\u003e\n\u003e\u003e OP_EVAL adds dangerously expressive power to the scripting language.\n\u003e\n\u003e If you look at the archives of the concatenative programming mailing\n\u003e list [1] you'll see lots of examples of people creating stack\n\u003e languages with minimal operations that exploit similar functionality\n\u003e to reduce the required built in operations. The discussion on the list\n\u003e is mostly about stack based languages where programs can be pushed on\n\u003e the stack and executed (eg. Joy [2]/Factor/Some Forths).\n\u003e\n\u003e I don't think the scripting engine in bitcoin has the ability to\n\u003e concatenate, append or otherwise manipulate scripts on the stack to be\n\u003e eval'd though does it?\n\nIt will limited ability manipulate scripts on the stack through the use of \narithmetic and hashing operations, and if OP_CAT, OP_SUBSTR and friends \nare ever restored, it will have even more abilities.\n\n-- \nRussell O'Connor \u003chttp://r6.ca/\u003e\n``All talk about `theft,''' the general counsel of the American Graphophone\nCompany wrote, ``is the merest claptrap, for there exists no property in\nideas musical, literary or artistic, except as defined by statute.''",
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