[Haskell-cafe] Re: Wikipedia on first-class object
barsoap at web.de
Mon Dec 31 05:34:34 EST 2007
"Cristian Baboi" <cristi at ot.onrc.ro> wrote:
> Well, it depends on what you think is nicer.
> For me it looks shorter than undefined and it don't rely on the
Well, for me undefined doesn't throw undeterministic behaviour at me
(throwing a stack overflow sooner or later or not, depending on
patience and stack size settings), it just fails in every case.
> > And then
> > let a = a
> > is more defined than the other two... only the equation is _|_, not
> > the value that is "assigned". Value that is equated? Term?
> > Jonathan, please beat me.
> This is over my head.
> If let a = a is more defined, then why (print a) won't stop ?
Because it's still _|_. It's just not defined to be undefined,
it's undefined by itself. Which, from my sometimes seriously twisted
point of view, makes it more defined, as it's not defined to be
undefined, by itself, seen from within it. From the outside, it's less
defined. Your terms may differ, the thing to distinguish is where _|_
comes into play to avoid having your thoughts looping forever.
To answer your question: because, in order to print a, print has to
force the chunk that's representing a, and that chunks needs to force
the chunk that's representing a, and that chunk needs to force the
chunk that's representing a, and that chunk needs to force the chunk
that's representing a, and that chunk...
(c) this sig last receiving data processing entity. Inspect headers for
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