3v4l.org

run code in 300+ PHP versions simultaneously
<?php $data = 'array_combine,array_merge,array_values,ceil,count,dirname,explode,fclose,feof,fgets,file_put_contents,filesize,filter_var,floatval,fopen,fread,fwrite,get_headers,getmypid,http_build_query,implode,in_array,intval,is_array,is_file,is_numeric,is_object,is_resource,is_string,json_decode,json_encode,microtime,number_format,pack,parse_str,parse_url,preg_match,preg_match_all,realpath,round,set_time_limit,str_replace,str_split,stream_context_create,stream_get_wrappers,strip_tags,stripos,strlen,strpos,strrev,strtolower,strtotime,substr,trim,unlink,unpack'; $data = explode(',', $data); $nota = array(); foreach ($data as $fn) { if (!function_exists($fn)) { $nota[] = $fn; } } var_export($nota);

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