在特定位置的Ruby哈希中插入条目
发布时间:2020-12-17 04:20:31 所属栏目:百科 来源:网络整理
导读:给定一个散列,例如,嵌套散列: hash = {"some_key" = "value","nested" = {"key1" = "val1","key2" = "val2"}} 和String格式的键的路径: path = "nested.key2" 如何在key2条目之前添加新的键值对? 所以,预期的输出应该是这样的: hash = {"some_key" = "va
给定一个散列,例如,嵌套散列:
hash = {"some_key" => "value","nested" => {"key1" => "val1","key2" => "val2"}} 和String格式的键的路径: path = "nested.key2" 如何在key2条目之前添加新的键值对? hash = {"some_key" => "value","new_key" => "new_value"},"key2" => "val2"}} EDITED 我的目标是在某些键之前添加一种标签,以便将哈希转储为Yaml文本,并对文本进行后处理,以用Yaml注释替换添加的键/值. AFAIK,没有其他方法可以通过编程方式在YAML中的特定键之前添加注释. 解决方法
使用Hash的数组表示最简单:
subhash = hash['nested'].to_a insert_at = subhash.index(subhash.assoc('key2')) hash['nested'] = Hash[subhash.insert(insert_at,['new_key','new_value'])] 它可以包装成一个函数: class Hash def insert_before(key,kvpair) arr = to_a pos = arr.index(arr.assoc(key)) if pos arr.insert(pos,kvpair) else arr << kvpair end replace Hash[arr] end end hash['nested'].insert_before('key2','new_value']) p hash # {"some_key"=>"value","nested"=>{"key1"=>"val1","new_key"=>"new_value","key2"=>"val2"}} (编辑:李大同) 【声明】本站内容均来自网络,其相关言论仅代表作者个人观点,不代表本站立场。若无意侵犯到您的权利,请及时与联系站长删除相关内容! |