import inspect,dis
def expecting():
"""Return how many values the caller is expecting"""
f = inspect.currentframe()
f = f.f_back.f_back
c = f.f_code
i = f.f_lasti
bytecode = c.co_code
instruction = ord(bytecode[i+3])
if instruction == dis.opmap['UNPACK_SEQUENCE']:
howmany = ord(bytecode[i+4])
return howmany
elif instruction == dis.opmap['POP_TOP']:
return 0
return 1
def cleverfunc():
howmany = expecting()
if howmany == 0:
print "return value discarded"
if howmany == 2:
return 1,2
elif howmany == 3:
return 1,2,3
return 1
def test():
cleverfunc()
x = cleverfunc()
print x
x,y = cleverfunc()
print x,y
x,y,z = cleverfunc()
print x,y,z
test()
