gnu: Move sparsehash to datastructures module.

* gnu/packages/crypto.scm (sparsehash): Move variable to...
* gnu/packages/datastructures.scm: ...new file.
* gnu-system.am (GNU_SYSTEM_MODULES): Add it.

gnu-system.am

@@ -80,6 +80,7 @@ GNU_SYSTEM_MODULES =				\
   gnu/packages/cyrus-sasl.scm			\
   gnu/packages/databases.scm			\
   gnu/packages/datamash.scm			\
+  gnu/packages/datastructures.scm		\
   gnu/packages/dc.scm				\
   gnu/packages/debug.scm			\
   gnu/packages/dejagnu.scm			\

gnu/packages/crypto.scm

@@ -43,28 +43,3 @@ (define-public libsodium
 communication, encryption, decryption, signatures, etc.")
     (license isc)
     (home-page "http://libsodium.org")))
-
-(define-public sparsehash
-  (package
-    (name "sparsehash")
-    (version "2.0.3")
-    (source (origin
-              (method url-fetch)
-              (uri (string-append "https://github.com/sparsehash/sparsehash/"
-                                  "archive/sparsehash-" version ".tar.gz"))
-              (sha256
-               (base32
-                "133szz0ldwch0kd91l0sa57qsnl020njn622szd9cxrjqyjqds85"))))
-    (build-system gnu-build-system)
-    (synopsis "Memory-efficient hashtable implementations")
-    (description
-     "This library contains several hash-map implementations, similar in API
-to SGI's @code{hash_map} class, but with different performance
-characteristics.  @code{sparse_hash_map} uses very little space overhead, 1-2
-bits per entry.  @code{dense_hash_map} is very fast, particulary on lookup.
-@code{sparse_hash_set} and @code{dense_hash_set} are the set versions of these
-routines.  All these implementation use a hashtable with internal quadratic
-probing.  This method is space-efficient -- there is no pointer overhead --
-and time-efficient for good hash functions.")
-    (home-page "https://github.com/sparsehash/sparsehash")
-    (license bsd-3)))

gnu/packages/datastructures.scm

+;;; GNU Guix --- Functional package management for GNU
+;;; Copyright © 2015 Ricardo Wurmus <rekado@elephly.net>
+;;;
+;;; This file is part of GNU Guix.
+;;;
+;;; GNU Guix 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.
+;;;
+;;; GNU Guix 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 GNU Guix.  If not, see <http://www.gnu.org/licenses/>.
+
+(define-module (gnu packages datastructures)
+  #:use-module (gnu packages)
+  #:use-module ((guix licenses) #:prefix license:)
+  #:use-module (guix packages)
+  #:use-module (guix download)
+  #:use-module (guix build-system gnu))
+
+(define-public sparsehash
+  (package
+    (name "sparsehash")
+    (version "2.0.3")
+    (source (origin
+              (method url-fetch)
+              (uri (string-append "https://github.com/sparsehash/sparsehash/"
+                                  "archive/sparsehash-" version ".tar.gz"))
+              (sha256
+               (base32
+                "133szz0ldwch0kd91l0sa57qsnl020njn622szd9cxrjqyjqds85"))))
+    (build-system gnu-build-system)
+    (synopsis "Memory-efficient hashtable implementations")
+    (description
+     "This library contains several hash-map implementations, similar in API
+to SGI's @code{hash_map} class, but with different performance
+characteristics.  @code{sparse_hash_map} uses very little space overhead, 1-2
+bits per entry.  @code{dense_hash_map} is very fast, particulary on lookup.
+@code{sparse_hash_set} and @code{dense_hash_set} are the set versions of these
+routines.  All these implementation use a hashtable with internal quadratic
+probing.  This method is space-efficient -- there is no pointer overhead --
+and time-efficient for good hash functions.")
+    (home-page "https://github.com/sparsehash/sparsehash")
+    (license license:bsd-3)))