'excluded', MY_CONSTANT => 'excluded', PHP_INT_MAX => 'excluded', str_replace('.', '', '1.1') => 'excluded', self::CONSTANT => 'excluded', $obj->get_key() => 'excluded', $obj->prop => 'excluded', "my $var text" => 'excluded', << 'excluded', $var['key']{1} => 'excluded', ]; /* * Let's find some duplicates. */ $emptyStringKey = array( '' => 'empty', // All below will error. null => 'null', (string) false => 'false', ); $everythingZero = [ '0', // All below will error. 0 => 'a', 0.0 => 'b', '0' => 'c', 0b0 => 'd', 0x0 => 'e', 00 => 'f', false => 'g', 0.4 => 'h', -0.8 => 'i', 0e0 => 'j', 0_0 => 'k', -1 + 1 => 'l', 3 * 0 => 'm', 00.00 => 'n', (int) 'nothing' => 'o', 15 > 200 => 'p', "0" => 'q', 0. => 'r', .0 => 's', (true) ? 0 : 1 => 't', ! true => 'u', ]; $everythingOne = [ '0', '1', // All below will error. 1 => 'a', 1.1 => 'b', '1' => 'c', 0b1 => 'd', 0x1 => 'e', 01 => 'f', true => 'g', 1.2 => 'h', 1e0 => 'i', 0_1 => 'j', -1 + 2 => 'k', 3 * 0.5 => 'l', 01.00 => 'm', (int) '1 penny' => 'n', 15 < 200 => 'o', "1" => 'p', 1. => 'q', 001. => 'r', (true) ? 1 : 0 => 's', ! false => 't', (string) true => 'u', ]; $everythingEleven = [ 11 => 'a', // All below will error. 11.0 => 'b', '11' => 'c', 0b1011 => 'd', 0Xb => 'e', 013 => 'f', 11.8 => 'g', 1.1e1 => 'h', 1_1 => 'i', 0_13 => 'j', -1 + 12 => 'k', 22 / 2 => 'l', 0011.0011 => 'm', (int) '11 lane' => 'n', "11" => 'o', 11. => 'p', 35 % 12 => 'q', ]; $textualStringKeyVariations = [ 'abc' => 1, 'def' => 2, 'ghi' => 3, // All below will error. 'ab' . 'c' => 4, // Error. << 5, // Error. <<< 'NOW' ghi NOW => 6, // Error. "abc" => 7, // Error. ]; $testKeepingTrackOfHighestIntKey = array( '' => 'empty', 'a', // Int 0 'b', // Int 1 1 => 'c', // Int 1 - Error. 5 => 'd', // Int 5 'e', // Int 6 6 => 'f', // Int 6 - Error. false => 'g', // Int 0 - Error. true => 'h', // Int 1 - Error. 1.1 => 'i', // Int 1 - Error. 6.5 => 'j', // Int 6 - Error. 05 => 'k', // Int 5 - Error. 0_6 => 'l', // Int 6 - Error. PHP 7.4 octal numeric literal. 0x1 => 'm', // Int 1 - Error. 0b0 => 'n', // Int 0 - Error. null => 'o', // Empty string - Error. 02.6e7 => 'p', // Int 26000000 '96' => 'q', // Int 96 'r', // Int 26000001 '26000001' => 's', // Int 26000001 - Error. '96.3' => 't', // String '96.3' 1 + 0 => 'u', // Int 1 - Error. 1.1 - 0.5 => 'v', // Int 0 - Error. -1 => 'w', // Int -1 'x', // Int 26000002 '9' . '6' => 'y', // Int 96 - Error. '1.' => 'z', // String '1.' ); $testPHPLt8VsPHP8 = array( -10 => 'a', 'b', // PHP < 8: int 0; PHP 8+: -9. 'c', // PHP < 8: int 1; PHP 8+: -8. -4 => 'd', 'e', // PHP < 8: int 2; PHP 8+: -3. -9 => 'f', // Duplicate in PHP 8, not in PHP < 8. -8 => 'g', // Duplicate in PHP 8, not in PHP < 8. -3 => 'h', // Duplicate in PHP 8, not in PHP < 8. 0 => 'i', // Duplicate in PHP < 8, not in PHP 8. 1 => 'j', // Duplicate in PHP < 8, not in PHP 8. 2 => 'k', // Duplicate in PHP < 8, not in PHP 8. );