+tasks/download_%:
+ if [ -z "$(url_$*)" ]; then echo "No url for $*" >&2; false; fi
+ mkdir -p download
+ cd download && wget --passive-ftp -N $(url_$*)
+ touch $@
+
+tasks/extract_%: tasks/download_%
+ mkdir -p build
+ cd build && \
+ gzip -dc ../download/$*-$(version_$*).tar.gz | $(TAR) -xf - && \
+ rm -f $* && \
+ ln -s $*-$(version_$*) $*
+ touch $@
+
+tasks/extract_darcs_%:
+ mkdir -p build
+ if [ -z "$(darcs_$*)" ]; then echo "No darcs url for $*" >&2; false; fi
+ cd build && darcs get --verbose "$(darcs_$*)"
+ touch $@
+
+update_darcs_%: tasks/extract_darcs_%
+ cd "build/$*" && darcs pull
+ rm "tasks/build_darcs_$*" # to force a rebuild
+
+tasks/build_darcs_%: tasks/extract_darcs_%
+ cd "build/$*" && make
+ touch $@
+