d: add experimental support for the D language

* configure.ac (ENABLE_D): New.
* src/getargs.c (valid_languages): Add d.

configure.ac

@@ -188,6 +188,15 @@ BISON_C_COMPILER_POSIXLY_CORRECT
 BISON_TEST_FOR_WORKING_CXX_COMPILER
 BISON_CXX_COMPILER_POSIXLY_CORRECT
 
+# D.
+AM_CONDITIONAL([ENABLE_D], [true])
+
+# Java.
+gt_JAVACOMP([1.7], [1.7])
+gt_JAVAEXEC
+AM_CONDITIONAL([ENABLE_JAVA], [test x"$CONF_JAVAC" != x && test x"$CONF_JAVA" != x])
+
+
 AC_ARG_ENABLE([yacc],
   [AC_HELP_STRING([--disable-yacc],
      [do not build a yacc command or an -ly library])],
@@ -278,10 +287,6 @@ AM_MISSING_PROG([AUTOM4TE], [autom4te])
 # Needed by tests/atlocal.in.
 AC_SUBST([GCC])
 
-gt_JAVACOMP([1.7], [1.7])
-gt_JAVAEXEC
-AM_CONDITIONAL([ENABLE_JAVA], [test x"$CONF_JAVAC" != x && test x"$CONF_JAVA" != x])
-
 AC_CONFIG_FILES([Makefile
                  po/Makefile.in
                  doc/yacc.1])

src/getargs.c

@@ -54,6 +54,7 @@ static struct bison_language const valid_languages[] = {
   /* lang,  skeleton,       ext,     hdr,     add_tab */
   { "c",    "c-skel.m4",    ".c",    ".h",    true },
   { "c++",  "c++-skel.m4",  ".cc",   ".hh",   true },
+  { "d",    "d-skel.m4",    ".d",    ".d",    false },
   { "java", "java-skel.m4", ".java", ".java", false },
   { "", "", "", "", false }
 };