> From: Andy Wingo <wi...@pobox.com> > Cc: l...@gnu.org, 10...@debbugs.gnu.org > Date: Tue, 19 Feb 2013 22:44:39 +0100 > > >> (define (canonical->suffix canon) > >> (cond > >> - ((string-prefix? "/" canon) canon) > >> - ((and (> (string-length canon) 2) > >> - (eqv? (string-ref canon 1) #\:)) > >> - ;; Paths like C:... transform to /C... > >> - (string-append "/" (substring canon 0 1) (substring canon 2))) > >> + ((and (not (string-null? canon)) > >> + (path-separator? (string-ref canon 0))) > >> + canon) > >> + ((and (eq? (system-path-convention) 'windows) > >> + (absolute-path? canon)) > >> + ;; An absolute path that doesn't start with a path separator starts > >> with a > >> + ;; drive component. Transform the drive component to a path > >> element: > >> + ;; c:\foo -> \c\foo. > > > > Why is this transformation needed? Native Windows system calls will > > not understand "/c/foo" syntax. What is this about? (I know it was > > in the original code, but I didn't understand it then, either.) > > Auto-compiling /foo/bar/baz.scm produces > $HOME/.cache/guile/2.0/ccache/foo/bar/baz.go. This turns the drive > component into a path element on Windows so compiling C:/foo.scm caches > $HOME/.cache/guile/2.0/ccache/c/foo.go.
Thanks, I see the light now. Perhaps consider adding a comment there pointing to this use of the transformation.
