Provide a useful regress target.

--- Makefile.orig	Sat Jul 26 00:39:17 2003
+++ Makefile	Thu Aug 14 13:07:07 2003
@@ -420,3 +420,23 @@
 
 # -----------------------------------------------------------------------------
 
+EXP=alex.expected
+OUT=alex.actual
+
+check::
+	@( cd alex/tests/ ; ${MAKE} 2>&1 | tee ../../${OUT}.raw )
+	@sed '1d;$$d' ${OUT}.raw > ${OUT}
+	@(if cmp -s ${EXP} ${OUT} ; then \
+		echo ;\
+		echo "All is good!" ; \
+		echo ;\
+	  else \
+		echo ;\
+		echo "@@@@@@@@@@@@@@@@@@@@@@@@@@@@";\
+		echo "Unexpected regress results!" ;\
+		echo "@@@@@@@@@@@@@@@@@@@@@@@@@@@@";\
+		echo ;\
+		echo "here is a diff:" ;\
+		diff -u ${EXP} ${OUT} ;\
+	  fi ; exit 0 )
+
