Re: destructuring

[George J. Carrette <GJC at MIT-MC>]

    Date: 3 February 1981 03:21-EST
    From: Daniel L. Weinreb <dlw at MIT-AI>

    The Lisp Machine does not implement PROG and DO by expanding them into
    lambdas, and it would be unresonably inefficient for it to do so.  So
    several things have to be changed.  This is only a minor subpoint anyway.


That is a nice & fine blanket statement there, widely used to justify
just about anything. Exactly what would inefficient?
Code produced by the compiler? The compiler itself? The interpreter?
System programmer effort? Maybe you can shed some light on this,
and tell why the obvious way is not good in this case.