[plt-scheme] Re: to define, or to let (last try)

From: Shriram Krishnamurthi (sk at cs.brown.edu)
Date: Wed Apr 28 23:09:56 EDT 2004

Bill Richter wrote:

>    It's long, long, long since lost any relevance to PLT Scheme.
> 
> IMO definite-semantics & good-programming-style are relevant to PLT
> Scheme.  

I'm going to entirely step around your response, which is very
cleverly worded to draw an N+1'th person into the fray -- so cleverly
worded that I nearly made the mistake of replying to its body.  (In
fact I began to, but then slapped myself upside the head and deleted
the prose I'd written.)

I will instead simply say this: PLT Scheme does left-to-right.  It
doesn't matter whether R5RS supports that or not, and it doesn't
matter whether Joe can argue that it's harmful.  That's just what it
does.  It has a very "definite semantics" in that respect.  Joe's
example simply means that the observational equivalence relation is a
bit tricky.  Whoever writes the optimizing compiler for PLT Scheme
will be grateful for that insight.

Now, until Matthew posts a survey on the topic here, l->r is what it's
going to do.  (Shades of Nelson Goodman here.)  Now that you know its
semantics, program with it or (if you're an acolyte of Joe and view
the world differently) around it.

Since it isn't going to change in the near future, this discussion has
nothing to do with PLT Scheme.

Go forth and write useful and beautiful code.

Shriram


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