Add support for Guile 2.0.9.

* gash/compat.scm: New file.
* gash/compat/hash-table.scm: New file.
* Makefile.am: Add them.
* .dir-locals.scm: Add indentation for 'if-guile-version-below'.
* guix.scm (guile-2.0.9): New variable.
* gash/built-ins/echo.scm (escape->control): Use '#\esc'.
* gash/environment.scm: Use '(gash compat hash-table)'.
* gash/built-ins/break.scm,
gash/built-ins/cd.scm,
gash/built-ins/command.scm,
gash/built-ins/continue.scm,
gash/built-ins/dot.scm,
gash/built-ins/exec.scm,
gash/built-ins/exit.scm,
gash/built-ins/pwd.scm,
gash/built-ins/return.scm,
gash/built-ins/set.scm,
gash/built-ins/shift.scm,
gash/built-ins/trap.scm,
gash/built-ins/type.scm,
gash/built-ins/umask.scm,
gash/eval.scm,
tests/unit/automake.scm: Use '(gash compat)'.

squash! Add support for Guile 2.0.9.

.dir-locals.el

@@ -6,6 +6,7 @@
                (let ((top (locate-dominating-file default-directory
                                                   ".dir-locals.el")))
                  (add-to-list 'geiser-guile-load-path top))))
+     (eval . (put 'if-guile-version-below 'scheme-indent-function 1))
      (eval . (put '<sh-case> 'scheme-indent-function 1))
      (eval . (put '<sh-defun> 'scheme-indent-function 1))
      (eval . (put '<sh-exec-let> 'scheme-indent-function 1))

Makefile.am

@@ -37,6 +37,8 @@ GUILE_MODULES =                                 \
   gash/built-ins/unset.scm                      \
   gash/built-ins/utils.scm                      \
   gash/built-ins.scm                            \
+  gash/compat/hash-table.scm                    \
+  gash/compat.scm                               \
   gash/config.scm                               \
   gash/environment.scm                          \
   gash/eval.scm                                 \

gash/built-ins/break.scm

@@ -17,6 +17,7 @@
 ;;; along with Gash.  If not, see <http://www.gnu.org/licenses/>.
 
 (define-module (gash built-ins break)
+  #:use-module (gash compat)
   #:use-module (gash environment))
 
 ;;; Commentary:

gash/built-ins/cd.scm

@@ -17,6 +17,7 @@
 ;;; along with Gash.  If not, see <http://www.gnu.org/licenses/>.
 
 (define-module (gash built-ins cd)
+  #:use-module (gash compat)
   #:use-module (gash environment)
   #:use-module (ice-9 match))
 

gash/built-ins/command.scm

@@ -20,6 +20,7 @@
 (define-module (gash built-ins command)
   #:use-module (ice-9 getopt-long)
   #:use-module (gash built-ins utils)
+  #:use-module (gash compat)
   #:use-module (gash config))
 
 ;;; Commentary:

gash/built-ins/continue.scm

@@ -17,6 +17,7 @@
 ;;; along with Gash.  If not, see <http://www.gnu.org/licenses/>.
 
 (define-module (gash built-ins continue)
+  #:use-module (gash compat)
   #:use-module (gash environment))
 
 ;;; Commentary:

gash/built-ins/dot.scm

@@ -18,6 +18,7 @@
 
 (define-module (gash built-ins dot)
   #:use-module (gash built-ins utils)
+  #:use-module (gash compat)
   #:use-module (gash environment)
   #:use-module (gash parser)
   #:use-module (ice-9 match))

gash/built-ins/echo.scm

@@ -42,7 +42,9 @@
                        ((#\a) (cons #\alarm (loop (cdr lst))))
                        ((#\b) (cons #\backspace (loop (cdr lst))))
                        ((#\c) '())
-                       ((#\e) (cons #\escape (loop (cdr lst))))
+                       ;; Guile 2.0.9 does not understand '#\escape',
+                       ;; so we use the older '#\esc'.
+                       ((#\e) (cons #\esc (loop (cdr lst))))
                        ((#\f) (cons #\page (loop (cdr lst))))
                        ((#\n) (cons #\newline (loop (cdr lst))))
                        ((#\r) (cons #\return (loop (cdr lst))))

gash/built-ins/exec.scm

@@ -17,6 +17,7 @@
 ;;; along with Gash.  If not, see <http://www.gnu.org/licenses/>.
 
 (define-module (gash built-ins exec)
+  #:use-module (gash compat)
   #:use-module (gash environment)
   #:use-module (ice-9 match)
   #:use-module (srfi srfi-1))

gash/built-ins/exit.scm

@@ -17,6 +17,7 @@
 ;;; along with Gash.  If not, see <http://www.gnu.org/licenses/>.
 
 (define-module (gash built-ins exit)
+  #:use-module (gash compat)
   #:use-module (gash environment))
 
 ;;; Commentary:

gash/built-ins/pwd.scm

@@ -17,6 +17,7 @@
 ;;; along with Gash.  If not, see <http://www.gnu.org/licenses/>.
 
 (define-module (gash built-ins pwd)
+  #:use-module (gash compat)
   #:use-module (gash environment)
   #:use-module (ice-9 match))
 

gash/built-ins/return.scm

@@ -17,6 +17,7 @@
 ;;; along with Gash.  If not, see <http://www.gnu.org/licenses/>.
 
 (define-module (gash built-ins return)
+  #:use-module (gash compat)
   #:use-module (gash environment))
 
 ;;; Commentary:

gash/built-ins/set.scm

@@ -18,6 +18,7 @@
 ;;; along with Gash.  If not, see <http://www.gnu.org/licenses/>.
 
 (define-module (gash built-ins set)
+  #:use-module (gash compat)
   #:use-module (gash environment)
   #:use-module (srfi srfi-26)
   #:use-module (ice-9 match))

gash/built-ins/shift.scm

@@ -17,6 +17,7 @@
 ;;; along with Gash.  If not, see <http://www.gnu.org/licenses/>.
 
 (define-module (gash built-ins shift)
+  #:use-module (gash compat)
   #:use-module (gash environment)
   #:use-module (ice-9 match)
   #:use-module (srfi srfi-1))

gash/built-ins/trap.scm

@@ -17,6 +17,7 @@
 ;;; along with Gash.  If not, see <http://www.gnu.org/licenses/>.
 
 (define-module (gash built-ins trap)
+  #:use-module (gash compat)
   #:use-module (gash environment)
   #:use-module (ice-9 match))
 

gash/built-ins/type.scm

@@ -20,6 +20,7 @@
 (define-module (gash built-ins type)
   #:use-module (ice-9 getopt-long)
   #:use-module (gash built-ins utils)
+  #:use-module (gash compat)
   #:use-module (gash config))
 
 ;;; Commentary:

gash/built-ins/umask.scm

@@ -17,6 +17,7 @@
 ;;; along with Gash.  If not, see <http://www.gnu.org/licenses/>.
 
 (define-module (gash built-ins umask)
+  #:use-module (gash compat)
   #:use-module (ice-9 match))
 
 ;;; Commentary:

gash/compat.scm

@@ -0,0 +1,58 @@
+;;; Gash -- Guile As SHell
+;;; Copyright © 2019 Timothy Sample <samplet@ngyro.com>
+;;;
+;;; This file is part of Gash.
+;;;
+;;; Gash 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.
+;;;
+;;; Gash 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 Gash.  If not, see <http://www.gnu.org/licenses/>.
+
+(define-module (gash compat)
+  #:export (if-guile-version-below))
+
+;;; Commentary:
+;;;
+;;; This module fills in for features that are missing in older
+;;; versions of the '(guile)' module.
+;;;
+;;; Code:
+
+(define-syntax if-guile-version-below
+  (lambda (x)
+    (define (guile-version<? major minor micro)
+      (let ((g-major (string->number (major-version)))
+            (g-minor (string->number (minor-version)))
+            (g-micro (string->number (micro-version))))
+        (or (< g-major major)
+            (and (= g-major major)
+                 (< g-minor minor))
+            (and (= g-major major)
+                 (= g-minor minor)
+                 (< g-micro micro)))))
+
+    (syntax-case x ()
+      ((_ (maj min mic) consequent alternate)
+       (if (guile-version<? (syntax->datum #'maj)
+                            (syntax->datum #'min)
+                            (syntax->datum #'mic))
+           #'consequent
+           #'alternate)))))
+
+(if-guile-version-below (2 0 10)
+  (begin
+    (define-public EXIT_SUCCESS 0)
+
+    (define-public EXIT_FAILURE 1)
+
+    (define-public (exact-integer? x)
+      (and (integer? x) (exact? x))))
+  #f)

gash/compat/hash-table.scm

@@ -0,0 +1,39 @@
+;;; Gash -- Guile As SHell
+;;; Copyright © 2019 Timothy Sample <samplet@ngyro.com>
+;;;
+;;; This file is part of Gash.
+;;;
+;;; Gash 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.
+;;;
+;;; Gash 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 Gash.  If not, see <http://www.gnu.org/licenses/>.
+
+(define-module (gash compat hash-table)
+  #:use-module (gash compat))
+
+;;; Commentary:
+;;;
+;;; The '(ice-9 hash-table)' module was introduced into Guile in
+;;; version 2.0.10, so we provide a shim.
+;;;
+;;; Code:
+
+(if-guile-version-below (2 0 10)
+  (begin
+    (define-public (alist->hash-table alist)
+      (let ((table (make-hash-table)))
+        (for-each (lambda (pair)
+                    (hash-set! table (car pair) (cdr pair)))
+                  (reverse alist))
+        table)))
+  (begin
+    (use-modules (ice-9 hash-table))
+    (re-export alist->hash-table)))

gash/environment.scm

@@ -18,7 +18,7 @@
 ;;; along with Gash.  If not, see <http://www.gnu.org/licenses/>.
 
 (define-module (gash environment)
-  #:use-module (ice-9 hash-table)
+  #:use-module (gash compat hash-table)
   #:use-module (ice-9 match)
   #:use-module (srfi srfi-1)
   #:use-module (srfi srfi-26)

gash/eval.scm

@@ -18,6 +18,7 @@
 ;;; along with Gash.  If not, see <http://www.gnu.org/licenses/>.
 
 (define-module (gash eval)
+  #:use-module (gash compat)
   #:use-module (gash environment)
   #:use-module (gash shell)
   #:use-module (gash word)

guix.scm

@@ -7,6 +7,7 @@
              (gnu packages texinfo)
              (guix build utils)
              (guix build-system gnu)
+             (guix download)
              (guix gexp)
              ((guix licenses) #:prefix license:)
              (guix packages)
@@ -47,6 +48,22 @@
       (or (eq? (stat:type stat) 'directory)
           (member relative paths)))))
 
+(define guile-2.0.9
+  (package
+    (inherit guile-2.0)
+    (version "2.0.9")
+    (source
+     (origin
+       (method url-fetch)
+       (uri (string-append "mirror://gnu/guile/guile-" version ".tar.xz"))
+       (sha256
+        (base32
+         "0nw9y8vjyz4r61v06p9msks5lm58pd91irmzg4k487vmv743h2pp"))))
+    (arguments
+     (substitute-keyword-arguments (package-arguments guile-2.0)
+       ;; XXX: There are some encoding and network test failures.
+       ((#:tests? _ #f) #f)))))
+
 (package
   (name "gash")
   (version *version*)

tests/unit/automake.scm

@@ -17,6 +17,7 @@
 ;;; along with Gash.  If not, see <http://www.gnu.org/licenses/>.
 
 (define-module (tests unit automake)
+  #:use-module (gash compat)
   #:use-module (srfi srfi-64))
 
 ;;; Commentary: