[plt-scheme] [redex] language keywords

From: Robby Findler (robby at eecs.northwestern.edu)
Date: Thu Jun 3 18:27:33 EDT 2010

On Thu, Jun 3, 2010 at 9:09 AM, Eric Tanter <etanter at dcc.uchile.cl> wrote:
> Is this 'where' clause something that was introduced somewhat recently?
> I remember from my first redex examples that the way to introduce a new identifier for instance was with ,(term-let ...).

Somewhat. As we gain experience (and your experience has been quite
helpful in this regard), Redex evolves to become better. I think you
already agreed this was better, no?

> The same question goes for the definition of metafunctions. For instance, the definition of lambda-v on the web:
> http://redex.plt-scheme.org/lam-v.html
> for the subst metafunction, uses ,(term-let ...) to introduce (x_new ...)
>
> It seems the preferred way to do that now would be with a where clause, right?

Right.

> (I was surprised actually when seeing in the doc that term-let was low-level and not meant to use, while it was--and still is in some cases-- used in the simple introductory examples of plt redex)
>

This was me not updating the website. Thank you for pointing it out. I
looked into updating it, but I found a bug in redex, so I'll leave it
alone until that gets fixed.

Robby


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