Re: [Haskell-cafe] idea for avoiding temporaries

I'm thinking you're missing the point. The point is to copy without writing, and that requires some knowledge (whether static or runtime) of whether anyone else has a reference to my data--which copy-on-write won't give me. David On Thu, Mar 08, 2007 at 11:15:25AM -0800, Dan Weston wrote:

Or possibly more generally copy-on-write, which requires one more level of indirection (handle instead of ptr). Since you are talking about using ForeignPtr, this is already within your power to prototype, I should think.

Dan

Dan Piponi wrote:

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On 3/8/07, David Roundy wrote:

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I started wondering whether there's a solution that would allow us to write pretty high-level pure functional code, while the RTS can realize at run-time that we have the only reference to the input argument and that it is therefore safe to consume it destructively.

I think you're talking about uniqueness typing which is supported by the programming language Clean.