Question

我的方法看起来像

def SomeMethod (*args)
     m = if args.length > 0 then 
            self.method(:method1) 
         else 
            self.method(:method2)
         end
     m.call ... #need to either pipe all arguments aside from the first
                #and in other cases substitute the first argument
end

实际结构更复杂，要调用的方法来自不同的实例，在某些情况下，我必须管道所有参数，以免第一个，在其他情况下，我必须用第一个参数替换第一个参数另一个值

Answer 1

您可以使用所谓的splat运算符*将数组扩展为参数列表：

# Call with all but the first element
m.call *args[1..-1]

# Replace first element
m.call *args[1..-1].unshift(newarg)

What does the (unary) * operator do in this Ruby code?
Weird multiplicator operator behavior in a two arrays to hash combination

Answer 2

您可以尝试使用哈希

def SomeMethod (hash_arg={})
    m = unless hash_arg.blank? then 
            self.method(:method1) 
        else 
            self.method(:method2)
        end
     m.call ... #need to either pipe all arguments aside from the first
            #and in other cases substitute the first argument
#Check if a certain arg has been passed=> do_something unless hash_arg[:certain_arg].nil?
end

将任意参数传递给方法

2 个答案: