def op_over(engine):
x2 = PushData.pop_stack_item(engine)
x1 = PushData.peek_stack_item(engine)
PushData.peek_stack_item(engine)
PushData.push(engine, x2)
PushData.push(engine, x1)
return VMState.NONE
def op_dup(engine):
items = PushData.peek_stack_item(engine)
PushData.push(engine, items)
return VMState.NONE
def op_nip(engine):
x2 = PushData.pop_stack_item(engine)
PushData.peek_stack_item(engine)
PushData.push(engine, x2)
return VMState.NONE
def op_x_tuck(engine):
n = PushData.pop_int(engine)
engine.evaluation_stack.insert(n, PushData.peek_stack_item(engine))
return VMState.NONE
