1

I am learning python and this is from 

http://www.learnpython.org/page/MultipleFunctionArguments

They have an example code that does not work- I am wondering if it is just a typo or if it should not work at all.

def bar(first, second, third, **options):
    if options.get("action") == "sum":
        print "The sum is: %d" % (first + second + third)

    if options.get("return") == "first":
        return first

result = bar(1, 2, 3, action = "sum", return = "first")
print "Result: %d" % result

Learnpython thinks the output should have been-

The sum is: 6
Result: 1

The error i get is-

Traceback (most recent call last):
  File "/base/data/home/apps/s~learnpythonjail/1.354953192642593048/main.py", line 99, in post
    exec(cmd, safe_globals)
  File "<string>", line 9
     result = bar(1, 2, 3, action = "sum", return = "first")
                                                ^
 SyntaxError: invalid syntax

Is there a way to do what they are trying to do or is the example wrong? Sorry I did look at the python tutorial someone had answered but I don't understand how to fix this.

4

2 回答 2

7

return是 python 中的关键字 - 你不能将它用作变量名。如果您将其更改为其他内容（例如ret），它将正常工作。

def bar(first, second, third, **options):
    if options.get("action") == "sum":
        print "The sum is: %d" % (first + second + third)

    if options.get("ret") == "first":
        return first

result = bar(1, 2, 3, action = "sum", ret = "first")
print "Result: %d" % result
于 2012-11-21T08:43:02.800 回答
1

您可能不应该使用“ return”作为参数名称，因为它是一个 Python 命令。

于 2012-11-21T08:44:14.317 回答