1 files changed, 47 insertions, 49 deletions

diff --git a/emacs/guix-main.scm b/emacs/guix-main.scm
index 5358f3bfa4..e645a85e7d 100644
--- a/emacs/guix-main.scm
+++ b/emacs/guix-main.scm
@@ -32,14 +32,6 @@
 ;; still "name-version" string.  So ‘id’ package parameter in the code
 ;; below is either an object-address number or a full-name string.
 
-;; To speed-up the process of getting information, the following
-;; auxiliary variables are used:
-;;
-;; - `%packages' - VHash of "package address"/"package" pairs.
-;;
-;; - `%package-table' - Hash table of
-;;   "name+version key"/"list of packages" pairs.
-
 ;;; Code:
 
 (use-modules
@@ -52,6 +44,7 @@
  (srfi srfi-19)
  (srfi srfi-26)
  (guix)
+ (guix combinators)
  (guix git-download)
  (guix packages)
  (guix profiles)
@@ -100,38 +93,6 @@ return two values: name and version.  For example, for SPEC
         (string-append full-name ":" output)
         full-name)))
 
-(define name+version->key cons)
-(define key->name+version car+cdr)
-
-(define %package-vhash
-  (delay
-    (fold-packages (lambda (pkg res)
-                     (vhash-consq (object-address pkg) pkg res))
-                   vlist-null)))
-
-(define (package-vhash)
-  "Return vhash of 'package ID (address)'/'package' pairs."
-  (force %package-vhash))
-
-(define %package-table
-  (delay
-    (let ((table (make-hash-table (vlist-length (package-vhash)))))
-      (vlist-for-each
-       (lambda (elem)
-         (match elem
-           ((address . pkg)
-            (let* ((key (name+version->key (package-name pkg)
-                                           (package-version pkg)))
-                   (ref (hash-ref table key)))
-              (hash-set! table key
-                         (if ref (cons pkg ref) (list pkg)))))))
-       (package-vhash))
-      table)))
-
-(define (package-table)
-  "Return hash table of 'name+version key'/'list of packages' pairs."
-  (force %package-table))
-
 (define (manifest-entry->name+version+output entry)
   (values
    (manifest-entry-name    entry)
@@ -339,15 +300,39 @@ Example:
 
 ;;; Finding packages.
 
-(define (package-by-address address)
-  (match (vhash-assq address (package-vhash))
-    ((_ . package) package)
-    (_ #f)))
-
-(define (packages-by-name+version name version)
-  (or (hash-ref (package-table)
-                (name+version->key name version))
-      '()))
+(define-values (package-by-address
+                register-package)
+  (let ((table (delay (fold-packages
+                       (lambda (package table)
+                         (vhash-consq (object-address package)
+                                      package table))
+                       vlist-null))))
+    (values
+     (lambda (address)
+       "Return package by its object ADDRESS."
+       (match (vhash-assq address (force table))
+         ((_ . package) package)
+         (_ #f)))
+     (lambda (package)
+       "Register PACKAGE by its 'object-address', so that later
+'package-by-address' can be used to access it."
+       (let ((table* (force table)))
+         (set! table
+               (delay (vhash-consq (object-address package)
+                                   package table*))))))))
+
+(define packages-by-name+version
+  (let ((table (delay (fold-packages
+                       (lambda (package table)
+                         (let ((file (location-file
+                                      (package-location package))))
+                           (vhash-cons (cons (package-name package)
+                                             (package-version package))
+                                       package table)))
+                       vlist-null))))
+    (lambda (name version)
+      "Return packages matching NAME and VERSION."
+      (vhash-fold* cons '() (cons name version) (force table)))))
 
 (define (packages-by-full-name full-name)
   (call-with-values
@@ -434,6 +419,15 @@ MATCH-PARAMS is a list of parameters that REGEXP can match."
               '()
               (find-newest-available-packages)))
 
+(define (packages-from-file file)
+  "Return a list of packages from FILE."
+  (let ((package (load (canonicalize-path file))))
+    (if (package? package)
+        (begin
+          (register-package package)
+          (list package))
+        '())))
+
 
 ;;; Making package/output patterns.
 
@@ -686,6 +680,8 @@ ENTRIES is a list of installed manifest entries."
                                    (lookup-license license-name))))
          (location-proc         (lambda (_ location)
                                   (packages-by-location-file location)))
+         (file-proc             (lambda (_ file)
+                                  (packages-from-file file)))
          (all-proc              (lambda _ (all-available-packages)))
          (newest-proc           (lambda _ (newest-available-packages))))
     `((package
@@ -696,6 +692,7 @@ ENTRIES is a list of installed manifest entries."
        (regexp           . ,regexp-proc)
        (license          . ,license-proc)
        (location         . ,location-proc)
+       (from-file        . ,file-proc)
        (all-available    . ,all-proc)
        (newest-available . ,newest-proc))
       (output
@@ -706,6 +703,7 @@ ENTRIES is a list of installed manifest entries."
        (regexp           . ,regexp-proc)
        (license          . ,license-proc)
        (location         . ,location-proc)
+       (from-file        . ,file-proc)
        (all-available    . ,all-proc)
        (newest-available . ,newest-proc)))))