Re: Request for potential addition Andre van Tonder 27 Mar 2004 02:23 UTC
On Fri, 26 Mar 2004 email@example.com wrote: > I have occasionally found myself wanting to expand a macro in another. > Now, it wouldn't work to just write the macro I wish to expand in CPS > or as a syntax computation, because it needs to be an arbitrary macro. > I'm not _entirely_ sure if this is a good idea yet, but I think it may > be: I request that a SYNTAX-EXPAND (or whatever it be named) be added > to the current specification: > > (SYNTAX-EXPAND <form>) ;syntactic computation > Expand FORM completely and syntactically return the expanded form. > > ('Syntactically return' is probably not the right term, but whatever.) > > It of course cannot be implemented as a regular syntactic computation, > so it needs lower-level macro system support. > > Again, I haven't thought much about how good an idea this is, but it > has proven to be useful to me in the past. In a way, this is the problem that syntax-computations was designed to solve, although of course you can only expand a syntactic computation and not an arbitrary macro using SYNTAX-RUN, or in intermediate steps of SYNTAX-BIND. Of course it would be useful to be able to do this for arbitrary macros, but I do not feel qualified to specify this and dealing with the potential subtleties of hygiene, phase separation (?), etc, that may be involved.