;;; GNU Guix --- Functional package management for GNU
;;; Copyright Â© 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)))
