在perl中过滤散列哈希

Question

我有一个哈希哈希,我需要过滤.我确实找到了如何进行查找,但它没有回答我的问题.

假设我有一个像这样的散列哈希:

my %HoH = (
    flintstones => {
        husband   => "fred",
        pal       => "barney",
        town      => "springfield"
    },
    jetsons => {
        husband   => "george",
        wife      => "jane",
        "his boy" => "elroy",
    },
    simpsons => {
        husband   => "homer",
        wife      => "marge",
        kid       => "bart",
        town      => "springfield",
    },
);

我想说我想要所有来自斯普林菲尔德的城镇居民.我想在输出中使用相同的哈希哈希,而不需要局外人.

my %HoH = (
    flintstones => {
        husband   => "fred",
        pal       => "barney",
        town      => "springfield"
    },
    simpsons => {
        husband   => "homer",
        wife      => "marge",
        kid       => "bart",
        town      => "springfield",
    },
);

它似乎很傻但无法弄清楚如何过滤结构.目标是在过滤后迭代所有的斯普林菲尔德人.

我当然做了一些研究,我最接近的是哈希切片.但他们似乎很可怕.

Answer 1

首先需要找到要删除的元素的键:

grep { $HoH{$_}{town} eq 'springfield' } keys(%HoH)

然后你删除它们:

delete $HoH{$_} for grep { $HoH{$_}{town} eq 'springfield' } keys(%HoH);

或者使用哈希切片:

delete @HoH{ grep { $HoH{$_}{town} eq 'springfield' } keys(%HoH) };