-clean:
- $(RM) $(foreach DOC,$(DOCS),$(addprefix $(DOC).,\
- acn acr alg aux bbl blg fmt glg glo gls log nav out pdf run.xml snm\
- tdo toc vrb xdy))
+img/%.png: fig/%.dot
+ dot -Tpng $< > $@
+
+clean: $(addprefix clean-,$(DOCS))
+ $(RM) -v $(FIGURES)
+
+clean-%:
+ $(RM) -v $(addprefix $(@:clean-=).,acn acr alg aux bbl blg fmt glg glo\
+ gls ist lof log lol lot out pdf tdo toc)