Hello Danny, Thank you for your elaborate response. This makes it quite easy for me to write the module file. I added "write" and "rm" to the module, which should make it complete.
What is the preferred way to include the module file to the package? Should I create another package with this file alone, and use it as a propagated input for graphviz? Kind regards, Roel Janssen Danny Milosavljevic writes: > Hi, > > On Mon, 09 May 2016 22:54:00 +0200 > Roel Janssen <r...@gnu.org> wrote: > >> it is automatically generated using SWIG. I had to experiment a bit to >> find out that the functions exposed in Guile did not have a namespace (gv.). > > You can add a prefix when importing, so the symbols of the module shouldn't > have a prefix - the user would end up with two prefixes (or would have to cut > the other prefix out and replace it or something). > > (use-modules ((gdb) #:renamer (symbol-prefix-proc 'gdb:))) > > See also <http://www.swig.org/Doc2.0/Guile.html>. > >> There are functions called "rm" and "write" which are obviously already >> used for other purposes in Scheme. These functions will have to be >> renamed or just left out of the Scheme module. > > The user can specify which symbols to import (and also rename stuff there if > needed) so I'd do nothing of the sort. > > (use-modules ((ice-9 popen) > #:select ((open-pipe . pipe-open) close-pipe) > #:renamer (symbol-prefix-proc 'unixy:))) > > It's true that people still use the form > > (use-modules (xxx)) > > without specifying what the final imported symbols are, but that's something > I consider bad practise in most cases (in any language - hey let's import > random stuff into my namespace and have which module it gets each function > from change on each package update. How about no?). > > For example, let's say you have two modules "a" and "b". > Let module "a" contain "select". > Let module "b" contain "write". > > Let's say you use it as > > (use-modules (a) (b)) > > ; main program > (write ...) > (select ...) > > Then it will use b's write, a's select in your program, repectively. Say you > release it and people use it. > > Now let's say someone devious (not really, it can make sense to him) adds > "select" to module "b". Suddenly your program will use b's select *even > though you didn't change anything in it*. > > Bad. > > A complete set to try this: > > $ export GUILE_LOAD_PATH=. > > ;;; a.scm > (define-module (a) #:export (select)) > (define (select) (display "a.select") (newline)) > > ;;; b.scm > (define-module (b) #:export (write select)) > (define (write) (display "b.write") (newline)) > (define (select) (display "b.select") (newline)) > > ;;; main.scm > (use-modules (a) (b)) > (write) > (select) > > Note that you do get warnings by guile > > WARNING: (guile-user): imported module (a) overrides core binding `select' > WARNING: (guile-user): `select' imported from both (a) and (b) > b.select > WARNING: (guile-user): imported module (b) overrides core binding `write' > b.write > > ... which is nice.
