[shepherd] 05/09: Remove example of the 'unknown' service.

[Ludovic Courtès]

civodul pushed a commit to branch wip-goopsless
in repository shepherd.

commit 814850de07a369e867d243da0705b5479e8eb081
Author: Ludovic Courtès <ludo@gnu.org>
AuthorDate: Wed Apr 5 18:22:11 2023 +0200

    Remove example of the 'unknown' service.
    
    This is a followup to 2afe1feeee4f2b23e9fa70bb8462b59d37f34f72.
    
    * doc/examples/_unknown.scm: Remove.
    * Makefile.am (EXTRA_DIST): Remove it.
---
 Makefile.am               |   1 -
 doc/examples/_unknown.scm | 153 ----------------------------------------------
 2 files changed, 154 deletions(-)

diff --git a/Makefile.am b/Makefile.am
index d3f7a82..6eba8d9 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -139,7 +139,6 @@ EXTRA_DIST +=                                       \
   ChangeLog-2003                               \
   $(templates)                                 \
   doc/examples/README                          \
-  doc/examples/_unknown.scm                    \
   doc/examples/wolfgangj.scm
 
 # Create the socket directory (aka. 'default-socket-dir'.)  Make it
diff --git a/doc/examples/_unknown.scm b/doc/examples/_unknown.scm
deleted file mode 100644
index fb639ab..0000000
--- a/doc/examples/_unknown.scm
+++ /dev/null
@@ -1,153 +0,0 @@
-;; _unknown.scm -- An example for an `unknown' service.
-;; Copyright (C) 2003 Wolfgang J�hrling <wolfgang@pro-linux.de>
-;;
-;; This file is part of the GNU Shepherd.
-;;
-;; The GNU Shepherd is free software; you can redistribute it and/or modify it
-;; under the terms of the GNU General Public License as published by
-;; the Free Software Foundation; either version 3 of the License, or (at
-;; your option) any later version.
-;;
-;; The GNU Shepherd is distributed in the hope that it will be useful, but
-;; WITHOUT ANY WARRANTY; without even the implied warranty of
-;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-;; GNU General Public License for more details.
-;;
-;; You should have received a copy of the GNU General Public License
-;; along with the GNU Shepherd.  If not, see <http://www.gnu.org/licenses/>.
-
-;; Return true if STR1 lacks a character that exists in STR2, but
-;; otherwise both are identical.
-(define (lacks-char-from? str1 str2)
-  (and (= (string-length str1)
-          (+ (string-length str2) 1))
-       (letrec ((next
-                 (lambda (pos)
-                   (and (not (= pos (string-length str1)))
-                        (or (string=? str2
-                                      (string-append
-                                       (substring str1 0 pos)
-                                       (substring str1
-                                                  (+ pos 1)
-                                                  (string-length str1))))
-                            (next (+ pos 1)))))))
-         (next 0))))
-
-;; Return true if either of STR1 and STR2 lacks a character found in
-;; the other one, but otherwise both are identical (e.g. as is the
-;; case for "blah" and "bla").
-(define (differs-by-missing-char? str1 str2)
-  (or (lacks-char-from? str1 str2)
-      (lacks-char-from? str2 str1)))
-
-;; Return true if the only difference between STR1 and STR2 is that a
-;; successive pair of characters is switched in one of them.
-(define (differs-by-switched-chars? str1 str2)
-  (and (= (string-length str1)
-          (string-length str2))
-       (> (string-length str1) 1)
-       (letrec ((next
-                 (lambda (pos)
-                   (and (not (= pos (string-length str1)))
-                        (or (string=? str2
-                                      (string-append
-                                       (substring str1 0 (- pos 1))
-                                       (string (string-ref str1 pos)
-                                               (string-ref str1 (- pos 1)))
-                                       (substring str1
-                                                  (+ pos 1)
-                                                  (string-length str1))))
-                            (next (+ pos 1)))))))
-         (next 1))))
-
-;; Return true if they differ by exactly one character (e.g. as is the
-;; case for "blah" and "bleh"), if it isn't the only one.
-(define (differs-by-one-char? str1 str2)
-  (and (= (string-length str1)
-          (string-length str2))
-       (> (string-length str1) 1)
-       (letrec ((next
-                 (lambda (pos found-difference)
-                   (if (= pos (string-length str1))
-                       found-difference
-                       (if (char=? (string-ref str1 pos)
-                                   (string-ref str2 pos))
-                           (next (+ pos 1) found-difference)
-                           (and (not found-difference)
-                                (next (+ pos 1) #t)))))))
-         (next 0 #f))))
-
-;; Return true if STR1 and STR2 are identical, except for case
-;; (e.g. this gives true for "foobar" and "FooBAR").
-(define (differs-only-in-case? str1 str2)
-  (and (not (string=? str1 str2))
-       (string-ci=? str1 str2)))
-
-;; Return true if STR1 and STR2 are `similar' strings, meaning that
-;; they only differ in a minor way.
-(define (similar? str1 str2)
-  (any (lambda (pred?)
-         (pred? str1 str2))
-       (list differs-by-missing-char?
-             differs-by-switched-chars?
-             differs-by-one-char?
-             differs-only-in-case?)))
-
-
-
-;; TODO
-;;  - We could look for non-running services first on `start' etc.
-;;  - We also should do `unknown-action' (if service is known)
-;;    - If doing this, we should enable the service to handle it
-;;  - Make this the `default unknown service'
-;;  - Messages if nothing found.
-
-;; Suggest a service that satisfies PRED?, if given, and has a name
-;; similar to SERVICE-SYMBOL.
-(define look-for-service
-  (case-lambda
-    ((service-symbol) (look-for-service service-symbol (lambda (x) #t)))
-    ((service-symbol pred?)
-     (call/ec
-      (lambda (return)
-        (for-each-service
-         (lambda (s)
-           (and (pred? s)
-                (similar? (symbol->string service-symbol)
-                          (symbol->string (canonical-name s)))
-                (begin
-                  (format #t "Did you mean ~a maybe?" (canonical-name s))
-                  (newline)
-                  (return #t)))))
-        #f)))))
-
-;; The classical compose.
-(define (compose f g)
-  (lambda (x)
-    (f (g x)))
-
-  (define unknown-service
-    (make <service>
-      #:provides '(unknown)
-      #:actions (make-actions
-                 (start
-                  "Called if user wants to start an unknown service."
-                  (lambda (running service-sym . args)
-                    (or (look-for-service service-sym (compose not running?))
-                        (look-for-service service-sym))
-                    running))
-                 (stop
-                  "Called if user wants to stop an unknown service."
-                  (lambda (running service-sym . args)
-                    (or (look-for-service service-sym running?)
-                        (look-for-service service-sym))
-                    running))
-                 (action
-                  "Called if user frobs an unknown service."
-                  (lambda (running service-sym the-action . args)
-                    (or (look-for-service service-sym running?)
-                        (look-for-service service-sym))
-                    running)))))
-
-  (register-services unknown-service)
-  (start unknown-service)