Re: [Scheme-reports] Some comments after reading the r7rs public draft

[John Cowan <cowan@x>]

Per Bothner scripsit:

> (Though a future version of Kawa might optimize (delay 4) to 4,
> that's OK, since I can't think of a use case for you needing
> the delay to evaluate specifically to a promise.)

As I keep saying, the use case is to be able to write procedures that
are guaranteed to return a promise that the caller may safely force.
The only way to accomplish this in the presence of insta-forcing is
to require `force` to return its argument if it is not a promise.

I'm going to put together a proposal to cover all this, I think.

-- 
John Cowan  <cowan@x>  http://ccil.org/~cowan
Micropayment advocates mistakenly believe that efficient allocation of
resources is the purpose of markets.  Efficiency is a byproduct of market
systems, not their goal.  The reasons markets work are not because users
have embraced efficiency but because markets are the best place to allow
users to maximize their preferences, and very often their preferences are
not for conservation of cheap resources.  --Clay Shirky

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