perl - 删除数组的 Perl 散列中的空字符串

Question

我有一个具有这种结构的散列

{
  a => ['1', '2', '', '5', '6', '7', '8'],
  b => ['1', '2', '3', '6', '7', '8', '9'],
  c => ['2', '', '4', '', '', '8', ''],
}

我需要这样的

{
  c => ['2', '4', '8'], 
  a => ['1', '2', '5', '6', '7', '8'], 
  b => ['1', '2', '3', '6', '7', '8', '9']
}

如何删除 '' 值？

Answer 1

您可以直接更改 values 返回的数组引用列表，如 perldoc 中所述.

use warnings;
my %h = (
  'c' => ['2','','4','','','8',''],
  'a' => ['1','2','','5','6','7','8'],
  'b' => ['1','2','3','6','7','8','9']
);

@$_ = grep defined && length, @$_ for values %h;

并且在不应过滤掉 undef 值的情况下，

@$_ = grep !defined || length, @$_ for values %h;