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run code in 300+ PHP versions simultaneously
<?php // string, null, bool, float, largest specified previous index function isIndexedArray($array) { return !(bool)count(array_filter(array_keys($array), 'is_string')); } assert(isIndexedArray(['a']));
Output for 5.5.0 - 5.5.38, 5.6.0 - 5.6.30, 7.0.0 - 7.0.20, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
preferences:
155.77 ms | 404 KiB | 284 Q