+preprocessed.but: puzzles.but
+ sed 's/PREFIX-/$(BINPREFIX)/g' puzzles.but > preprocessed.but
+
+puzzles.chm: preprocessed.but
+ halibut --chm=puzzles.chm preprocessed.but
+puzzles.hlp: preprocessed.but
+ halibut --winhelp=puzzles.hlp preprocessed.but
+puzzles.txt: preprocessed.but
+ halibut --text=puzzles.txt preprocessed.but