将字符串数组转换为字符串数组

Question

我的目标是将这个

my @array=("red", "blue", "green", ["purple", "orange"]);

进入到这个

my @array = ( ["red"], ["blue"], ["green"], ["purple", "orange"]);

当前测试代码：

my @array = ("red", "blue", "green", ["purple", "orange"] );

foreach $item ( @array ) {
   #if this was Python, it would be as simple as:
   #  if is not instance(item, array):
   #     # item wasn't a list
   #     item = [item]

   if(ref($item) ne 'ARRAY'){
      #It's an array reference...
      #you can read it with $item->[1]
      #or dereference it uisng @newarray = @{$item}
      #print "We've got an array!!\n";
      print $item, "\n";
      # keep a copy of our string
      $temp = $item;
      # re-use the variable but convert to an empty list
      @item = ();
      # add the temp-copy as first list item
      @item[0] = $temp;
      # print each list item (should be just one item)
      print "$_\n" for $item;
   }else{
      #not an array in any way...
       print "ALREADY an array!!\n";

   }
}

#  EXPECTED my @array=(["red"], ["blue"], ["green"], ["purple", "orange"]);
print @array , "\n";

foreach $item (@array){
    if(ref($item) ne 'ARRAY'){
    #
    #say for $item;
    print "didn't convert properly to array\n";
   }
}

Answer 1

关于python的注释相当直接地映射到perl。

my @array = ("red", "blue", "green", ["purple", "orange"] );

foreach $item ( @array ) {
   #if this was Python, it would be as simple as:
   #  if is not instance(item, array):
   #     # item wasn't a list
   #     item = [item]
   if (ref $item ne 'ARRAY') {
       $item = [ $item ];
   }
}

不过，使用Borodin的答案中的map会更自然。

Answer 2

我想知道你为什么要这么做，但这是

@array = map { ref ? $_ : [ $_ ] } @array

请不要调用数组@array；这就是@的作用。

你的评论太荒谬了

#if this was Python, it would be as simple as:
#  if is not instance(item, array):
#     # item wasn't a list
#     item = [item]

如果您熟悉Perl，那么就不需要问这个问题了。您必须知道，没有从Python到Perl的一对一转换。Python的表现力远不如Perl或C，但我无法想象您会要求简单地转换为C。

请克服你的偏执。

Answer 3

如果将值推入新数组，只需计算$item是否为arrayref即可：

#! perl

use strict;
use warnings;

use Data::Dumper;

my @array=("red", "blue", "green", ["purple", "orange"]);

my @new_array;
foreach my $item (@array) {

    if ( ref($item) eq  'ARRAY' ) {
        push @new_array, $item;
    }
    else {
        push @new_array, [$item];
    }
}

print Dumper \@new_array;

Dumper的输出：

$VAR1 = [
          [
            'red'
          ],
          [
            'blue'
          ],
          [
            'green'
          ],
          [
            'purple',
            'orange'
          ]
        ];