+puzzles.hlp puzzles.txt: preprocessed.but
+ halibut --winhelp=puzzles.hlp --text=puzzles.txt preprocessed.but
+
+HACKING: devel.but
+ halibut --text=HACKING devel.but
+
+chm: puzzles.hhp
+puzzles.hhp: puzzles.but chm.but
+ halibut --html puzzles.but chm.but
+
+clean:
+ rm -f puzzles.hlp puzzles.txt preprocessed.but HACKING *.html *.hh[pck]