这个Ruby语法是什么？

Question

我刚看了下面的代码:

class Dir
   def self.create_uniq &b  ### Here, & should mean b is a block
      u = 0
      loop do
      begin
         fn = b[u]   ### But, what does b[u] mean? And b is not called.
         FileUtils.mkdir fn
         return fn
      rescue Errno::EEXIST
         u += 1
      end
    end
    io
  end
end

我把我的困惑作为评论在代码中.

Answer 1

最后定义方法&b允许您使用传递给方法的块作为Proc对象.

现在,如果你有Proc实例,[]语法是简写call:

p = Proc.new { |u| puts u }
p['some string']
# some string
# => nil

记录在这里 - > Proc#[]