GNU make is lacking the feature to find out how many arguments a macro/user-defined function was called with. The code presented below helps in finding that out and pushes that value in the make variable $#.
The max number of arguments that are computable is 16^4 = 65,536. (limited by the MAX_INT variable) # *-*-* vim settings *-*-* # :set list ts=3 SHELL := /bin/sh X16 := X X X X X16 += $(X16) X16 += $(X16) NULL := SPC := $(NULL) $(NULL) hash := \# [0-9] := 0 1 2 3 4 5 6 7 8 9 define MAX_INT $(strip \ $(foreach i,$(X16), \ $(foreach j,$(X16), \ $(foreach k,$(X16),$(X16))))) endef # # Iterator function # # $(call iterator,$1,$2,$3) # $1 => list to iterate upon # $2 => target text # $3 => function name define iterator $(strip \ $(if $(word 2,$1), \ $(call iterator,$(strip \ $(wordlist 2,$(words $1),$1)),$(strip \ $(call $3,$(word 1,$1),$2)),$(strip \ $3)), \ $(call $3,$(word 1,$1),$2))) endef # $(call split,$1) $1 is number which will be split into digits define split $(strip \ $(eval _op = $$(subst $$1,$$1$(SPC),$$2))\ $(call iterator,$([0-9]),$1,_op)\ $(eval undefine _op)) endef # $(call _halving_algo,$1,$2) $1 and $2 are digits define _halving_algo $(strip \ $(subst $(SPC),,\ $(if $(filter 0 2 4 6 8,$1),\ $(if $(filter 0 1,$2),0,\ $(if $(filter 2 3,$2),1,\ $(if $(filter 4 5,$2),2,\ $(if $(filter 6 7,$2),3,\ $(if $(filter 8 9,$2),4))))),\ $(if $(filter 0 1,$2),5,\ $(if $(filter 2 3,$2),6,\ $(if $(filter 4 5,$2),7,\ $(if $(filter 6 7,$2),8,\ $(if $(filter 8 9,$2),9)))))))) endef # $(call _halve,$1) $1 is number split into individuval digits define _halve $(strip \ $(if $(word 3,$1),\ $(call _halving_algo,$(word 1,$1),$(word 2,$1))$(call _halve,$(wordlist 2,$(words $1),$1)),\ $(call _halving_algo,$(word 1,$1),$(word 2,$1)))) endef # $(call halve,$1) $1 is a number define halve $(if $(filter 0 1,$1),0,$(patsubst 0%,%,$(call _halve,$(call split,0$1)))) endef # $(call powers_of_2,$1) $1 define powers_of_2 $(if $(filter 0,$1),,$(call powers_of_2,$(call halve,$1)) $1) endef POWERS_OF_2 := $(strip $(call powers_of_2,$(words $(MAX_INT)))) # GNU make code that determines the number of arguments passed to a macro/function define NbArgs $$(eval $$$$(hash) := 0)$$(eval keepgoing := 1)\ $$(foreach i,$$(POWERS_OF_2),\ $$(if $$(keepgoing),\ $$(if $$(filter undefined,$$(origin $$i)),\ $$(foreach j,$$(words $$(wordlist 1,$$#,$$(MAX_INT))),\ $$(if $$(keepgoing),\ $$(if $$(filter undefined,$$(origin $$(words $$(wordlist 1,$$#,$$(MAX_INT)) X))),\ $$(eval keepgoing :=),\ $$(eval $$$$(hash) = $$(words $$(wordlist 1,$$#,$$(MAX_INT)) X))))),\ $$(eval $$$$(hash) := $$i)))) endef # demo macro/function called with different number of arguments define fx $(strip \ $(eval $(NbArgs))\ $(subst a,XX,abcd)) endef #x := $(call fx) #x := $(call fx,a) #x := $(call fx,a,b) #x := $(call fx,a,b,c) x := $(call fx,a,b,c,d) #x := $(call fx,a,b,c,d,e,1,2,3,4,5,6,7,8,9,10) $(info $$#=[$#]) $(info $x) .PHONY: all modif_4_uplod modif_dnlod all:; @: modif_4_uplod: $(CODE) sed -e 'G' $^ > $^.uplod; \ vi $^.uplod modif_dnlod: $(CODE) sed -e 'N;s/\n$$//;P;D' $^ > $^.dnlod _______________________________________________ Help-make mailing list Help-make@gnu.org https://lists.gnu.org/mailman/listinfo/help-make
