ruby hash value array append new element

ruby 中的hash 初始化value 为array

mh = Hash.new(Array.new)
mh[3]  << 4
irb(main):034:0> mh[3]
=> [4]
irb(main):035:0> mh
=> {}

无法直接采用上述方式追加元素；

可采用如下形式，

ht1 = Hash.new {|h,k| h[k]=[]}

原文地址：https://www.cnblogs.com/lavin/p/11022943.html

时间： 2024-11-08 23:04:43

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