Most likely, the content of @list_words is not what you think it is. Maybe it contains terminal control codes, or one single large line.

Note that you output @list_words twice, with no delimiter in between, which will make debugging this much harder.

My first attempt at debugging this would be to add some non-whitespace characters around the elements of @list_words while printing them, and cut down @list_words to say 10 elements that you can also share here:

splice @list_words, 10; # inspect only the first 10 elements

use Data::Dumper;
local $Data::Dumper::Useqq = 1; # output strings with whitespace chara
+cters escaped

while (scalar @list_words) {
  test_if_letters_are_included();

  foreach(@list_words) {
    print "list_words:<$_>\n";
    print Dumper $_; # also show the string with whitespace escaped
  }
  my @array = qw(this that the other thing);
  print "@array";
  #say "@list_words";
  say scalar @list_words;
}

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In reply to Re: Bizarre Perl behavior? by Corion
in thread Bizarre Perl behavior? by Polymathic

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