[plt-scheme] to define, or to let

From: Richard Cleis (rcleis at mac.com)
Date: Sat Mar 20 22:10:17 EST 2004

Syntax: <Bindings> should have the form ((<variable1> <init1>) ...),

One restriction on letrec is very important: it must be possible to 
evaluate each <init> without assigning or referring to the value of any 
<variable>. If this restriction is violated, then it is an error.

Welcome to DrScheme, version 206p1.
Language: Standard (R5RS).
 > (letrec ((any-variable 'value-of-any-variable)
            (referring-to-the-value any-variable))


On Mar 20, 2004, at 1:39 PM, Robby Findler wrote:

> At Sat, 20 Mar 2004 11:08:11 -0700, Richard Cleis wrote:
>>   For list-related administrative tasks:
>>   http://list.cs.brown.edu/mailman/listinfo/plt-scheme
>> PLT allows E2 to depend on a's value even with the language set to
>> R5RS, so letrec appears to be let*rec.
> I'm pretty sure you're mis-reading the spec, but if you post a (small)
> program and a (short) precise reason why what you see doesn't match the
> spec, we may be able to find out for sure.
> If you like, search for letrec in Help Desk to read what r5rs really
> says.
> Robby

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