I recall that the reader can be hash-extended to read these forms in a hacky way. Extend on '-'. I don't recall exactly anymore. I long ago patched the reader to read these natively. Perhaps there is some enthusiasm for making these readable in the main line?
Cheers, Dan On Aug 24, 2010, at 12:38 PM, l...@gnu.org (Ludovic Courtès) wrote: > Hi, > > Richard Shann <richard.sh...@virgin.net> writes: > >> I am displaying a structure that seems to be circular, and it shows >> >> (x_LIST . #-3#) >> >> x_LIST is my own symbol but what is the meaning of the other member of the >> pair? > > Indeed, it means it’s a circular list: > > --8<---------------cut here---------------start------------->8--- > scheme@(guile-user)> (use-modules (srfi srfi-1)) > scheme@(guile-user)> (circular-list 1 2 3) > $1 = (1 2 3 . #-2#) > scheme@(guile-user)> (circular-list 1) > $2 = (1 . #0#) > --8<---------------cut here---------------end--------------->8--- > >> And how does one track it down this notation in the guile manual? I am >> sure I came across this before, but cannot locate it in the manual >> (again?) > > It doesn’t seem to be documented but you get the idea. ;-) > > Note that ‘read’ doesn’t understand it. > > Thanks, > Ludo’. > >
