ARMASM MACRO

How to define amount of arguments in macro and to touch them in a cycle?
pseudocode
MACRO
funcname %arg1,$arg2...$argN
LCLA count
count SETA ??? ;num args
WHILE count>0
arg[count]
count SETA count-1
WEND
MEND
pseudocode
MACRO
funcname %arg1,$arg2...$argN
LCLA count
count SETA ??? ;num args
WHILE count>0
arg[count]
count SETA count-1
WEND
MEND