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run code in 150+ php & hhvm versions
Bugs & Features
<?php $option = 'max_file_size'; preg_match_all( '#((?:^|[A-Z])[a-z]+)#', $option, $matches ); if ( isset( $matches[1] ) && strlen( strtolower( implode( '_', $matches[1] ) ) ) >= strlen( $option ) ) { $option = strtolower( implode( '_', $matches[1] ) ); } var_dump( $option );
Output for 4.3.0 - 7.1.0
string(13) "max_file_size"