Re: [Haskell-cafe] Re: Re[2]: Tuple-like constructors

Robert Dockins wrote:

[Moved to cafe; time to stop bothering the Haskell' committee...]

On Feb 8, 2006, at 1:19 PM, Malcolm Wallace wrote:

...

Robert Dockins writes:

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instance (Bin a,Bin b,Bin c,Bin d) => Bin (a,b,c,d)

See the problem? Sooner or later (probably sooner) I'll get tired of typing. I have to write down an 'instance' declaration for each value of n. Clearly this can't generalize to all n.

Wouldn't it be nice to have dependent types? (I'm also thinking of all the numerical algorithms that could benefit from such an extension, but I don't know what syntax one could use) Regards, Brian.