This page is part of the web mail archives of SRFI 1 from before July 7th, 2015. The new archives for SRFI 1 contain all messages, not just those from before July 7th, 2015.
I have made what I hope are final changes to the SRFI-1 list library. There are three sets of changes: - I've added CONCATENATE and CONCATENATE!. (concatenate lists) = (apply append lists) The problem with the APPLY/APPEND idiom is that you can blow out many Scheme implementations if you apply an n-ary function to too many arguments. This has been a problem in Scheme 48, for example. CONCATENATE doesn't have this problem. - I've made UNFOLD be the name of the function that generates list elements left-to-right, and UNFOLD-RIGHT be the name of the function that generates list elements right-to-left. This is in keeping with the general use of the FOO and FOO-RIGHT convention. I originally had these backwards. Note that left fold & right unfold are inverses, as are right fold and left unfold (which is what led me astray). It's important to get this straight now, to establish a convention for other unfolders on other composite data structures (e.g., strings & vectors). - I've added some functions from the Haskell list library: split-at lis i -> [list, list] split-at! lis i -> [list, list] take-while pred lis -> list take-while! pred lis -> list drop-while pred lis -> list span pred lis -> [list list] span! pred lis -> [list list] break pred lis -> [list list] break! pred lis -> [list list] I apologise for making more additions and changes to the library; it is way past time to put this thing to bed. These changes have been incorporated into the draft spec & source found at ftp://ftp.ai.mit.edu/people/shivers/srfi/srfi-1/srfi-1.html ftp://ftp.ai.mit.edu/people/shivers/srfi/srfi-1/srfi-1.txt ftp://ftp.ai.mit.edu/people/shivers/srfi/srfi-1/srfi-1-reference.scm I have polished these documents to a ready-to-go-final state. Note that the html spec has an "active" procedure index, with internal links to all the procedure definitions, so you can easily jump to the definitions of the new procedures if you wish to check them out. Today is Sunday. If I hear no complaints by Friday, SRFI-1 will be moved to "final." -Olin