Please install perl. \
))
+$(eval $(call RequireCommand,python, \
+ Please install python. \
+))
+
$(eval $(call RequireCommand,wget, \
Please install wget. \
))
$(eval $(call Require,gnu-find, \
Please install GNU find \
))
+
+define Require/getopt-extended
+ getopt --long - - >/dev/null
+endef
+
+$(eval $(call Require,getopt-extended, \
+ Please install an extended getopt version that supports --long \
+))