gnu: Add python2-langkit.

* gnu/packages/ada.scm: New file.

gnu/packages/ada.scm

@@ -0,0 +1,61 @@
+;;; GNU Guix --- Functional package management for GNU
+;;; Copyright © 2018 Danny Milosavljevic <dannym@scratchpost.org>
+;;;
+;;; 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 ada)
+  #:use-module ((guix licenses) #:prefix license:)
+  #:use-module (guix build-system gnu)
+  #:use-module (guix build-system python)
+  #:use-module (guix packages)
+  #:use-module (guix download)
+  #:use-module (guix git-download)
+  #:use-module (gnu packages)
+  #:use-module (gnu packages check)
+  #:use-module (gnu packages compression)
+  #:use-module (gnu packages python))
+
+(define-public python2-langkit
+  (let ((commit "fe0bc8bf60dbd2937759810df76ac420d99fc15f")
+        (revision "0"))
+    (package
+      (name "python2-langkit")
+      (version (git-version "0.0.0" revision commit))
+      (source (origin
+                (method git-fetch)
+                (uri (git-reference
+                      (url "https://github.com/AdaCore/langkit.git")
+                      (commit commit)))
+                (sha256
+                 (base32
+                  "1abqgw2p8pb1pm54my5kkbbixfhc6l0bwajdv1xlzyrh31xki3wx"))
+                (file-name (string-append name "-" version "-checkout"))))
+      (build-system python-build-system)
+      (propagated-inputs
+       `(("python2-docutils" ,python2-docutils)
+         ("python2-enum34" ,python2-enum34)
+         ("python2-funcy" ,python2-funcy)
+         ("python2-mako" ,python2-mako)))
+      (arguments
+       `(#:python ,python-2
+         #:tests? #f))           ; Tests would requite gprbuild (Ada).
+      (synopsis "Semantic analysis tool generator in Python")
+      (description "@code{Langkit} is a tool whose purpose is to make it easy
+to create syntactic and semantic analysis engines.  Write a language
+specification in our Python DSL and Langkit will generate for you an
+Ada library with bindings for the C and Python programming languages.")
+      (home-page "https://github.com/AdaCore/langkit/")
+      (license license:gpl3+))))   ; and gcc runtime library exception