<br><div><span class="gmail_quote">On 5/31/07, <b class="gmail_sendername">Carl Eastlund</b> <<a href="mailto:cce@ccs.neu.edu">cce@ccs.neu.edu</a>> wrote:</span><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;"> > In principle, a closure is essentially a struct.  All that needs to be<br>> stored is a code pointer and references to any free variables.  How<br>> efficient this is in practice depends a lot on the particular <br>> implementation.  Are you asking in general, or about PLT Scheme<br>> specifically?</blockquote><div><br>I am specifically interested in PLT Scheme (general info is also of interest but secondary). <br> <br> Does closure hold references to the stack?  I've heard that Scheme doesn't keep variables on the stack, but want to verify.  <br> <br> If closure is as efficient as a struct that's great - I am finding myself leaning toward closure because it can be created anonymously and ad hoc, but doing so with struct is a lot harder. <br> <br> Thanks,<br> yinso <br><br></div></div>