[plt-scheme] about letrec and continuation : which behavior is correct ? and why ?

From: Matthias Felleisen (matthias at ccs.neu.edu)
Date: Tue Aug 19 12:45:12 EDT 2008

On Aug 19, 2008, at 12:26 PM, Chongkai Zhu wrote:

> Matthias Felleisen wrote:
>> I assume w/ "incorrect" you mean "is not a legal program".
>> It never ceases to amaze me that the Report specifies that some
>> syntactically legal expressions are NOT programs but you can only
>> find out (as far as I know) that they are NOT programs by RUNNING
>> them. (Of course all this means is that compilers and interpreters
>> accept and deal with 'things' that are not legal programs in the
>> spirit of a report, though I can't think of another language with
>> this property.)
> Being a dynamic-typed language, a lot of syntactically legal  
> expression are not programs.

Try harder :-) 

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