In article <ae74261c-e7e8-4a56-b708-b5b135a3f...@p-cos.net>, Pascal Costanza <p...@p-cos.net> wrote:
> Hi, > > I'm thinking about writing up a CDR on #;-style comments. Currently, if you > want to comment out a form from CL code, there is no standard way of doing > this. Many people use something like #+nil, or similar tricks, but this is > not 100% reliable. R6RS Scheme introduced #; as a solution, and this seems to > become somewhat popular in CL as well. > > Here is a suggested wording. > > ------------- snip ----------------- > > #; is used to comment out single expressions; the syntax is /#; expression/. > This textual notation is treated as whitespace; that is, it is as if the ``#; > expression'' did not appear and only a space appeared in its place. > > #; operates by skipping over the form. Skipping over the form is accomplished > by binding *read-suppress* to true and then calling read. > > ------------- snip ----------------- > > The text is based on 2.4.8.17 of the HyperSpec. Yes, this would be a fairly > short CDR document. > > Any comments or ideas about this? I don't see the need for it. #+nil will work just fine de facto. And for the paranoid, there's the trick that Robert Smith mentioned (#+#:foo). The only thing that could make it interesting because it'd add something to the table, is to allow e.g. #2; to comment out the next two forms. It sounds a bit insane, though. T PS. According to Figure 2-19 in CLHS 2.4.8, #, is not explicitly reserved for the user (most likely as #, was something akin to LOAD-TIME-VALUE in CLtL1.) I just wanted to point that out in case you do write a CDR where you might want to mention it. > > > Best, > Pascal > > -- > Pascal Costanza _______________________________________________ pro mailing list pro@common-lisp.net http://lists.common-lisp.net/cgi-bin/mailman/listinfo/pro