I wish to extract an element from a list, ie (a,b,c) => (a,c). However this list is a tad complex

$a[0][0] = ['00', '01'];
$a[0][1] = ['10', '11'];
DB<69> x @a[0]
0  ARRAY(0x55bb8ce673d8)
   0  ARRAY(0x55bb8ce5b430)
      0  00
      1  01
   1  ARRAY(0x55bb8d543fb8)
      0  10
      1  11

[download]

The closest I've been able to get is:

DB<69> x @a[0]
0  ARRAY(0x55bb8ce673d8)
   0 undef
   1  ARRAY(0x55bb8d543fb8)
      0  10
      1  11

[download]

Using delete but I've been unable to get rid of the undef. Oh, List::UtilsBy::extract_by {...} was not successful.

In reply to extracting a list element by geoffleach

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