define a variable containing a single space

blank := space := $(blank) $(blank)

split string $3 with $1 as separator and return the token in position $2

define token $(word $2, $(subst $1, ,$3)) endef

split string $3 with $1 as separator and reassemble it using the indexes in $2

define reorder $(subst $(space),$1,$(foreach i,$2,$(call token,$1,$i,$3))) endef