[climacs-devel] Re: regex

[Nicolas Sceaux]

Lawrence Mitchell <wencel at gmail.com> writes:

> After discussing alternatives here and with Edi, it seems like
> the way forward is to modify cl-ppcre to change all occurances of
> (SCHAR *STRING* ...) and the like in the sources to some function
> that returns a character in a Climacs buffer.
>
> That is, rather than doing (scan regex string) and then matching
> in string, do (scan regex buffer) and somehow match in buffer.

OK, I think I managed to have SCAN do its job on a buffer instead of a
string. On a fresh image:

---- test.lisp ----
(in-package :common-lisp-user)
(defpackage :climacs-buffer
  (:use #:cl)
  (:export #:buffer #:size #:buffer-object #:buffer-substring))

(in-package :climacs-buffer)
;;; fake buffer implementation, for testing
(defclass buffer ()
  ((contents :initarg :contents)))

(defmethod size ((buffer buffer))
  (length (slot-value buffer 'contents)))

(defmethod buffer-object ((buffer buffer) offset)
  (aref (slot-value buffer 'contents) offset))

(defmethod buffer-substring ((buffer buffer) start &optional (end (size buffer)))
  (subseq (slot-value buffer 'contents) start end))

(in-package :common-lisp-user)

(defvar *buffer* (make-instance 'climacs-buffer:buffer :contents "
salut les amis. Comment allez-vous tous les 4 ?"))

(pushnew :climacs-ppcre *features*)

(asdf:oos 'asdf:compile-op :cl-ppcre)
(asdf:oos 'asdf:load-op :cl-ppcre)
---- test.lisp ----

;;;; Compile file /home/nicolas/lisp/climacs-ppcre/test.lisp ...
...
CL-USER> (cl-ppcre:scan "\\w+\\s+(\\d+)" *buffer*)
41
46
#(45)
#(46)
CL-USER> (climacs-buffer:buffer-substring *buffer* 41 46)
"les 4"

which seems not bad.

I'll clean a bit my hacks on CL-PPCRE and then send them here.

Nicolas