Wow...really pleased I asked. Those are great examples and I'm sure I'll learn a lot from them. I've needed to process lists/trees most of programming "life" and the languages I've used haven't exactly regarded them as first class citizens and this has slowed me down quite a lot. I don't have that problem now and despite my lack of familiarity and needing to look a lot of stuff up....the results are extremely rewarding. Thank you all for your help and advice.
Best Regards Dean On 7 February 2017 at 08:50, Jon Kleiser <jon.klei...@ceres.no> wrote: > Hi, > > I wasn’t aware of nor, nand, nond. Maybe there should have been a few more > “See also” in the docs. > > /Jon > > > On 7. Feb, 2017, at 08:31, Alexander Burger <a...@software-lab.de> wrote: > > > > On Tue, Feb 07, 2017 at 08:13:06AM +0100, Alexander Burger wrote: > >> Better to use (not Lst). > > > > One more note: I even try to avoid 'not' whenever possible, as it is an > > additional function call overhead. > > > > It is often possible to use the complementary flow function, > > like (ifn Lst ..) instead of (if (not Lst) ..). > > > > if <-> ifn > > and <-> nor > > or <-> nand > > when <-> unless > > cond <-> nond > > while <-> until > > > > ♪♫ Alex > > -- > >