Anyway something like "yield" would be very nice to have. Would it be hard to implement? It could be in a similar way to scala where you can define for-comprehensions. I really miss them in R. best wishes ferdinand
On Tue, Apr 1, 2008 at 12:32 PM, Luke Tierney <[EMAIL PROTECTED]> wrote: > No. First class continuations of the kind provided in scheme can be > used as a means to implement generators, but downward-only > continuations as currently provided in R are not sufficient for that. > This version is intended only as a non-local exit mechanism. > > Best, > > luke > > On Mon, 31 Mar 2008, f.jamitzky wrote: > > > > > callcc is similar to the "yield" keyword in python and c# > > it lets you define e.g. a generator of lists of numbers. > > > > > > > > > > Gabor Grothendieck wrote: > >> > >> Would anyone like to explain if callCC in R 2.7.0 gives > >> anything that on.exit does not already provide? > >> > >> It seems that the exit condition once defined cannot > >> be added to overridden whereas with on.exit multiple > >> on.exit's add additional on.exits rather than being ignored. > >> > >> Is this important? > >> > >> ______________________________________________ > >> R-devel@r-project.org mailing list > >> https://stat.ethz.ch/mailman/listinfo/r-devel > >> > >> > > > > > > -- > Luke Tierney > Chair, Statistics and Actuarial Science > Ralph E. Wareham Professor of Mathematical Sciences > University of Iowa Phone: 319-335-3386 > Department of Statistics and Fax: 319-335-3017 > Actuarial Science > 241 Schaeffer Hall email: [EMAIL PROTECTED] > Iowa City, IA 52242 WWW: http://www.stat.uiowa.edu > -- ################################################################################# Dr. Ferdinand Jamitzky Leibniz Supercomputing Centre of the Bavarian Academy of Sciences and Humanities Boltzmannstraße 1 85748 Garching bei München Phone: ++49-89-35831-8727 Fax: ++49-89-35831-9700 Mobile: 0177 - 829 3 649 e-mail: [EMAIL PROTECTED] ################################################################################# ______________________________________________ R-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel
