ruby - Ruby 中的双管道是什么(不是 ||= )？

Question

任何人都可以向我解释一下双管道 |i| 在这个例子中代表什么或被称为什么？

(1..10).detect {|i| (1..10).include?(i * 3)}

Answer 1

这是在 Ruby 中声明 block 参数的语法。

阅读Cycling and Looping—a.k.a. Iteration

Let’s look at that iterator in more depth:

@names.each do |name|
  puts "Hello #{name}!"
end

#each is a method that accepts a block of code then runs that block of code for every element in a list, and the bit between do and end is just such a block. A block is like an anonymous function or lambda. The variable between pipe characters is the parameter for this block.