【发布时间】:2014-05-27 21:28:45
【问题描述】:
my_hash = Hash.new{|h,k| h[k] = []}
name = 'John'
my_hash[name] << '7'
my_hash[name] << '9'
name = 'Jane'
my_hash[name] << '7'
my_hash[name] << 'J'
array_info = my_hash.values_at('John')
puts array_info.class => array
array_info.each do |ele|
puts ele => 7, 9
end
removed = array_info.include?('7')
puts removed => false ??!?!?????
array_info 刚刚打印了 7 作为数组中的一个元素,所以我们知道它存在。那么为什么 array_info.include?('7') 不会返回 true 呢?
【问题讨论】: