Re: [Haskell-cafe] Re: US Homeland Security program language security risks

On Sun, 06 Jan 2008 17:19:31 +0200, Daniel Fischer wrote:

Am Sonntag, 6. Januar 2008 15:54 schrieb Achim Schneider:

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Daniel Fischer wrote:

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Am Sonntag, 6. Januar 2008 15:18 schrieb Andrew Coppin:

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Daniel Fischer wrote:

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Just because I don't know: what bugs would be possible in a language having only the instruction return ()

Bug #1: You cannot write any nontrivial programs. ;-)

That's not a bug, that's a feature.

That's an interesting task: Design a non-touring complete, restricted language in which every expression is decidable, without making the language unusable for usual programming problems.

I'm not a logician, but didn't Gödel prove that you couldn't express the (full) arithmetic of natural numbers in such a language? Of course it might be possible to express a sufficiently interesting part of it, but I should be surprised.

Neither do I, but if you have non turing algorithms, maybe you could do it.