1# http://www.gnu.org/software/make/manual/make.html#Syntax-of-Functions
2,:= ,
3empty:=
4space:= $(empty) $(empty)
5foo:= a b c
6bar:= $(subst $(space),$,,$(foo))
7# bar is now `,abc'
8# space in `,$(foo)' replaced with `$', which will be empty
9
10test:
11	echo $(bar)
12