On 19-Sep-07, at 11:48 PM, Nick Alexander wrote:
> > > On 19-Sep-07, at 8:09 PM, William Stein wrote: > >> >> On 9/19/07, [EMAIL PROTECTED] <[EMAIL PROTECTED]> wrote: >>> I am rather fond of the '..' operator, though I can see why people >>> wouldn't want to add it as an official part of sage. This got me to >> >> I think the decision about whether or not to include something like >> this is definitely not decided yet. I personally also really like >> the >> [a..b] notation, since I really enjoyed using it in Magma, and I >> think perhaps the complaints about 0 or 1-based are misplaced, >> because with the [a..b] notation one is being completely explicit >> about the lower endpoint. Also, the closed brackets very very >> very strongly suggest "include the endpoint", like the do in standard >> mathematical notation. Also, I was not convinced that preparsing >> [a..b] is not possible in general (though Nick was worried about >> this).\ > > It's not that it's not possible, it's that soon you have to parse > arbitrary python code, or accept that you can break the preprocessor. > >> I am going to wait a while to see what brews up, even though >> the majority vote was against [a..b]. >> >> At a minimum I would like to implement that for the preparser (or >> have somebody else do so), and see what it feels like to use in >> practice >> in Sage. > > I think tomorrow I will do this, and perhaps refactor the preparser > slightly while I am there. It seems like we should be able to use > open and half open intervals, so not only > [1..2] and (0..3) are valid but also are [0..2) and (0..2] are. Having just read this, and thought about the ubiquity of parentheses, I think I'll try for [1..2] and ]2..3[ instead :) It looks alien, but it's more likely to parse. Although in mathematical python code, square brackets are very common too :) Nick --~--~---------~--~----~------------~-------~--~----~ To post to this group, send email to [email protected] To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/sage-devel URLs: http://sage.scipy.org/sage/ and http://modular.math.washington.edu/sage/ -~----------~----~----~----~------~----~------~--~---
