Perl用一组键来哈希 [英] Perl hashes with an array of keys

问题描述

给定一个包含n个元素（n大于1）的数组，是否有一种优雅的方式来引用散列结构中的元素，其中每个元素都是关键字？

例如：

  my @foo =（'a'，'b'，'z'）; 
  

考虑到这个或类似的东西，我想访问以下内容：

  $ hash-> {'a'}  - > {'b'}  - > {'z'} 
  

如果这是一个固定数量的元素，它会很简单，但我不知道在运行时它会有多少肯定不会超过6或7，但否则无法推测）。

我能想到的唯一模式都涉及循环和引用，看起来很笨拙。是否有东西不占用半页或需要Data :: Dumper，如果你有一个打字错误只是为了调试？

解决方案

这就是为什么 Data :: Diver 存在的原因：

 ＃！/ usr / bin / perl 
使用警告; 
使用strict; 
 
使用Data :: Diver qw {Dive}; 
 
 my $ hash = {a => {b => {z => '这里' } } }; 
 
我的@foo = qw（a b z）; 
 
 print Dive（$ hash，@foo）; 
  

Given an array which contains n elements (n more than 1), is there an elegant way to refer to the element in a hash structure where each element is the key in sequence?

For example:

my @foo = ('a','b','z');

Given this or something similar, I'd like to access the following:

$hash->{'a'}->{'b'}->{'z'}

If this was a fixed number of elements it would be simple, but I won't know how many it will be at runtime (certainly never more than 6 or 7, but otherwise unguessable).

The only patterns I can think of all involve loops and references and look clumsy. Is there something that doesn't take up a half a page or require Data::Dumper if you have a typo in it just to debug?

解决方案

That's why Data::Diver exists:

#!/usr/bin/perl
use warnings;
use strict;

use Data::Diver qw{ Dive };

my $hash = { a => { b => { z => 'HERE' } } };

my @foo = qw( a b z );

print Dive($hash, @foo);

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