如何防止位置参数扩展为关键字参数？

I'd like to have a method that accepts a hash and an optional keyword argument. I tried defining a method like this:

我想要一个接受哈希和可选关键字参数的方法。我尝试定义这样的方法：

def foo_of_thing_plus_amount(thing, amount: 10)
  thing[:foo] + amount
end

When I invoke this method with the keyword argument, it works as I expect:

当我使用关键字参数调用此方法时，它按预期工作：

my_thing = {foo: 1, bar: 2}
foo_of_thing_plus_amount(my_thing, amount: 20) # => 21

When I leave out the keyword argument, however, the hash gets eaten:

但是，当我省略关键字参数时，哈希会被吃掉：

foo_of_thing_plus_amount(my_thing) # => ArgumentError: unknown keywords: foo, bar

How can I prevent this from happening? Is there such a thing as an anti-splat?

我怎样才能防止这种情况发生？有没有像防啪啪一样的东西？

2 个解决方案

#1

This is a bug that was fixed in Ruby 2.0.0-p247, see this issue.

这是在Ruby 2.0.0-p247中修复的错误，请参阅此问题。

#2

What about

关于什么

def foo_of_thing_plus_amount(thing, opt={amount: 10})
  thing[:foo] + opt[:amount]
end

my_thing = {foo: 1, bar: 2}   # {:foo=>1, :bar=>2}
foo_of_thing_plus_amount(my_thing, amount: 20)   # 21
foo_of_thing_plus_amount(my_thing)   # 11

？

#1