emacs: Add interface for licenses.

* emacs/guix-main.scm (%license-param-alist): New variable.
  (license->sexp, find-licenses, license-entries): New procedures.
* emacs/guix-license.el (guix-license-get-entries)
  (guix-license-get-display, guix-license-insert-packages-button)
  (guix-license-insert-comment, guix-license-list-describe)
  (guix-license-list-show-packages): New procedures.
  (guix-licenses): New command.
* doc/emacs.texi (Emacs Licenses): New node.
  (Emacs Interface): Add it.
* doc/guix.texi (Top): Add it.
* NEWS: Mention new interface.

1 files changed, 22 insertions, 0 deletions

diff --git a/emacs/guix-main.scm b/emacs/guix-main.scm
index bec26c7c40..335686ed25 100644
--- a/emacs/guix-main.scm
+++ b/emacs/guix-main.scm
@@ -1083,3 +1083,25 @@ Return #t if the shell command was executed successfully."
   "Return a license URI by its name."
   (and=> (lookup-license name)
          license-uri))
+
+(define %license-param-alist
+  `((id      . ,license-name)
+    (name    . ,license-name)
+    (url     . ,license-uri)
+    (comment . ,license-comment)))
+
+(define license->sexp
+  (object-transformer %license-param-alist))
+
+(define (find-licenses search-type . search-values)
+  "Return a list of licenses depending on SEARCH-TYPE and SEARCH-VALUES."
+  (case search-type
+    ((id name)
+     (let ((names search-values))
+       (filter-map lookup-license names)))
+    ((all)
+     (licenses))))
+
+(define (license-entries search-type . search-values)
+  (map license->sexp
+       (apply find-licenses search-type search-values)))