= vs ->

D. Tweed tweed@compsci.bristol.ac.uk
Fri, 12 Oct 2001 09:24:40 +0100 (BST)

On Fri, 12 Oct 2001, Fergus Henderson wrote:

[Dave Tweed wrote]
> > sense. I'm not sure why anymore but Haskell changed the `if clause after
> > the value' to `pattern guard | before =', so I agree it now looks as if
> > it's stating that the pattern guard is equal to the rhs. 
> I've heard that the company which trademarked "Miranda" also obtained
> a design patent on using syntax like that in a programming language.
> The enforcibility of such a design patent is IMHO legally dubious,
> and the application of design patents to programming languages has
> never been tested in court as far as I am aware.  But nevertheless
> the mere existence of such a design patent was probably a significant
> disincentive to using that syntax.

Drifting very quickly offtopic, but this amused me... I think it was
probably me that you heard that from (if it was on a post to the main
haskell mailing list a couple of years ago.) I was `sure' then that that
was the case, having been told independently by two people that was the
reason. However, given that no-one from the Haskell comittee corroborated
this, and I'd imagine that it isn't something that people would be afraid
to admit on the Haskell list (unlike a more fanatical place like /.]), I'm
no longer `sure' that the people infrorming me were correct :-)

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