On 1/12/13, David A. Wheeler <dwhee...@dwheeler.com> wrote: > R7RS includes "datum labels" (see section 2.4), e.g., #0=(a b c . #0#). > > Sweet-expressions don't currently say anything specific about them. What, > if anything, should we do about datum labels? In particular, should we > provided a syntax to describe them for indentation processing, and if so, > what would it be?!? > > The "easy" way to deal with them is to not provide any particular syntax for > them at sweet-expression level, and presume that if they're supported, > they're supported at the n-expression level. None of our implementations > support datum labels either, though obviously that could be added. > > If we're to support them directly in sweet-expressions, I guess we support > something like this: > #0= > ! a b c . #0# > > It's not clear at all that these are common enough to need the complexity - > and it would be complexity! - in sweet-expression processing. However, > generality is valuable. > > --- David A. Wheeler
If ever, I propose that: foo ! #0= bar(x) nitz ! #0# ==> (foo #0=((bar x) nitz) #0#) while: foo ! #0=bar(x) nitz ! #0# ==> (foo (#0=(bar x) nitz) #0#) In addition, I propose that: foo ! bar(x) #0= quux(y) ! #0# ==> (foo ((bar x) . #0= ((quux y))) #0#) while: foo ! bar(x) #0=quux(y) ! #0# ==> (foo ((bar x) #0=(quux y)) #0#) ----- That said, I think datum labels are gonna be hard to implement in a BNF. Sincerely, AmkG ------------------------------------------------------------------------------ Master Visual Studio, SharePoint, SQL, ASP.NET, C# 2012, HTML5, CSS, MVC, Windows 8 Apps, JavaScript and much more. Keep your skills current with LearnDevNow - 3,200 step-by-step video tutorials by Microsoft MVPs and experts. SALE $99.99 this month only -- learn more at: http://p.sf.net/sfu/learnmore_122412 _______________________________________________ Readable-discuss mailing list Readable-discuss@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/readable-discuss
