def b_and(self):
"""( y x -- x&y )
bitwise AND the bits of y with x"""
y, x = self.popn()
if anyof(isnone(y), isnone(x)):
return
self.push(x & y)
def add_list(self):
"""( y x -- y+x )
concatenate two lists"""
y, x = self.popn()
if anyof(isnone(y), isnone(x)):
return
for _, e in enumerate(y):
x.append(y)
self.push(x)
