gnu: Add docbook-xsl-ns.

* gnu/packages/docbook.scm (docbook-xsl-ns): New variable.

gnu/packages/docbook.scm

@@ -41,6 +41,7 @@ (define-module (gnu packages docbook)
   #:use-module (guix packages)
   #:use-module (guix download)
   #:use-module ((guix build utils) #:select (alist-replace))
+  #:use-module (guix build-system copy)
   #:use-module (guix build-system gnu)
   #:use-module (guix build-system trivial)
   #:use-module (guix build-system python))
@@ -229,6 +230,61 @@ (define name-version
      "This package provides XSL style sheets for DocBook.")
     (license (license:x11-style "" "See 'COPYING' file."))))
 
+(define-public docbook-xsl-ns
+  (package
+    (name "docbook-xsl-ns")
+    (version "1.79.1")
+    (source (origin
+              (method url-fetch)
+              (uri (string-append "mirror://sourceforge/docbook/"
+                                  name "/" version "/"
+                                  name "-" version ".tar.bz2"))
+              (sha256
+               (base32
+                "170ggf5dgjar65kkn5n33kvjr3pdinpj66nnxfx8b2avw0k91jin"))))
+    (build-system copy-build-system)
+    (outputs '("out" "doc"))
+    (arguments
+     `(#:phases
+       (modify-phases %standard-phases
+         ;; XXX: The copy-build-system doesn't seem to allow installing to a
+         ;; different output.
+         (replace 'install
+           (lambda* (#:key outputs #:allow-other-keys)
+             (let* ((out (assoc-ref outputs "out"))
+                    (xml (string-append out "/xml/xsl/" ,name "-" ,version))
+                    (doc (string-append (assoc-ref %outputs "doc")
+                                        "/share/doc/" ,name "-" ,version))
+                    (select-rx (make-regexp
+                                "(\\.xml$|\\.xsl$|\\.dtd$|\\.ent$)")))
+               ;; Install catalog.
+               (install-file "catalog.xml" xml)
+               (install-file "VERSION.xsl" xml)
+               (substitute* (string-append xml "/catalog.xml")
+                 (("rewritePrefix=\"./")
+                  (string-append "rewritePrefix=\"file://" xml "/")))
+               ;; Install style sheets.
+               (for-each (lambda (dir)
+                           (for-each (lambda (f)
+                                       (install-file
+                                        f (string-append xml "/" (dirname f))))
+                                     (find-files dir select-rx)))
+                         '("assembly" "common" "eclipse" "epub" "epub3" "fo"
+                           "highlighting" "html" "htmlhelp" "javahelp" "lib"
+                           "manpages" "params" "profiling" "roundtrip"
+                           "template" "website"
+                           "xhtml" "xhtml-1_1" "xhtml5"))
+               ;; Install documentation.
+               (install-file "NEWS" doc)
+               (install-file "RELEASE-NOTES.html" doc)
+               (copy-recursively "slides" doc)
+               (copy-recursively "webhelp" doc)))))))
+    (home-page "https://docbook.org")
+    (synopsis "DocBook XSL namespaced style sheets for document authoring")
+    (description "This package provides the @emph{namespaced} XSL style sheets
+for DocBook.")
+    (license (license:x11-style "" "See 'COPYING' file."))))
+
 (define-public docbook-dsssl
   (package
     (name "docbook-dsssl")