>Hello, all. >I've been on this for almost a month now. I'm working on a project for my >work, where we need a console to control automation. I wanted to use an >existing language instead of developing one, and I thought Guile would be a >good choice. Basically, I want the user to be able to open a repl shell, >but by default it should have *no* bindings except the ones I whitelisted.
>For example, (getcwd) should fail, even (if #t #t #f) should say that "if" >isn't defined. Then I can add in only the procedures I want (plus a couple >automation commands). Does anyone know how to do this? I'm at my wit's end. >I was thinking I could get a list of all the language bindings and un-bind >them in one fell swoop, but I haven't found a way to do that. Hello Ryan, Define a module in a file with the "#:pure" option so that it starts off empty. Import what you need. Look at ice-9/safe-r5rs.scm for an example. Probably in /usr/share/guile/3.0/ice-9/safe-r5rs.scm Let's say your new module was (ryan stuff) and it could only do display and eqv? (define-module (ryan stuff) #:pure #:use-module ((guile) #:select (display eqv?) #:re-export (display eqv?)) To resolve the module (define m (resolve '(ryan stuff))) To eval in module (eval <expression> m) To make primitive repl (define (main) (let ((m (resolve-module '(ryan stuff)))) (display "> ") (let loop ((expr (read))) (write (false-if-exception (eval expr m))) (newline) (display "> ") (loop (read))))) (main) But fix primitive repl with better error handling than 'false-if-exception'. And add your own meta-commands. Using the real repl is probably a no-go, since it has meta-commands like ",m" that would let the user ignore your whitelist. I didn't really test this, but it should be mostly correct. Regards, Mike Gran
