46638582

php -a
Interactive shell

php > $str="[@Homer Jay Simpson](id:homer) is a good guy.";
php > preg_match('#(\[@([^\]])())#', $str, $matches);print_r($matches);
Array
(
    [0] => [@H
    [1] => [@H
    [2] => H
    [3] =>
)
php > preg_match('#(\[@([^\]+])())#', $str, $matches);print_r($matches);
Array
(
    [0] => [@H
    [1] => [@H
    [2] => H
    [3] =>
)
php > preg_match('#(\[@([^\]+]\])())#', $str, $matches);print_r($matches);
Array
(
)
php > preg_match('#(\[@([^\]]+)())#', $str, $matches);print_r($matches);
Array
(
    [0] => [@Homer Jay Simpson
    [1] => [@Homer Jay Simpson
    [2] => Homer Jay Simpson
    [3] =>
)
php > preg_match('#(\[@([^\]]+\])())#', $str, $matches);print_r($matches);
Array
(
    [0] => [@Homer Jay Simpson]
    [1] => [@Homer Jay Simpson]
    [2] => Homer Jay Simpson]
    [3] =>
)
php > preg_match('#(\[@[^\]]+())#', $str, $matches);print_r($matches);
Array
(
    [0] => [@Homer Jay Simpson
    [1] => [@Homer Jay Simpson
    [2] =>
)
php > preg_match('#(\([@[^\]]+)\]())#', $str, $matches);print_r($matches);
PHP Warning:  preg_match(): Compilation failed: unmatched parentheses at offset 16 in php shell code on line 1

Warning: preg_match(): Compilation failed: unmatched parentheses at offset 16 in php shell code on line 1
Array
(
    [0] => [@Homer Jay Simpson
    [1] => [@Homer Jay Simpson
    [2] =>
)
php > preg_match('#(\([@[^\]]+)())#', $str, $matches);print_r($matches);
PHP Warning:  preg_match(): Compilation failed: unmatched parentheses at offset 14 in php shell code on line 1

Warning: preg_match(): Compilation failed: unmatched parentheses at offset 14 in php shell code on line 1
Array
(
    [0] => [@Homer Jay Simpson
    [1] => [@Homer Jay Simpson
    [2] =>
)
php > preg_match('#(\[@[^\]]+())#', $str, $matches);print_r($matches);
Array
(
    [0] => [@Homer Jay Simpson
    [1] => [@Homer Jay Simpson
    [2] =>
)
php > preg_match('#(\[@([^\]]+)())#', $str, $matches);print_r($matches);
Array
(
    [0] => [@Homer Jay Simpson
    [1] => [@Homer Jay Simpson
    [2] => Homer Jay Simpson
    [3] =>
)
php > preg_match('#(\[@([^\]]+)\]())#', $str, $matches);print_r($matches);
Array
(
    [0] => [@Homer Jay Simpson]
    [1] => [@Homer Jay Simpson]
    [2] => Homer Jay Simpson
    [3] =>
)
php > echo $str;
[@Homer Jay Simpson](id:homer) is a good guy.
php > preg_match('#(\[@([^\]]+)\]\((id:([^)]+))\))#', $str, $matches);print_r($matches);
Array
(
    [0] => [@Homer Jay Simpson](id:homer)
    [1] => [@Homer Jay Simpson](id:homer)
    [2] => Homer Jay Simpson
    [3] => id:homer
    [4] => homer
)
php > preg_match('#(\[@([^\]]+)\]\((?:id:([^)]+))\))#', $str, $matches);print_r($matches);
Array
(
    [0] => [@Homer Jay Simpson](id:homer)
    [1] => [@Homer Jay Simpson](id:homer)
    [2] => Homer Jay Simpson
    [3] => homer
)
php > preg_match('#(?:\[@([^\]]+)\]\((?:id:([^)]+))\))#', $str, $matches);print_r($matches);
Array
(
    [0] => [@Homer Jay Simpson](id:homer)
    [1] => Homer Jay Simpson
    [2] => homer
)
php > preg_match('#(?:\[@([^\]]+)\]\(id:([^)]+)\))#', $str, $matches);print_r($matches);
Array
(
    [0] => [@Homer Jay Simpson](id:homer)
    [1] => Homer Jay Simpson
    [2] => homer
)
php > preg_match('#\[@([^\]]+)\]\(id:([^)]+)\)#', $str, $matches);print_r($matches);
Array
(
    [0] => [@Homer Jay Simpson](id:homer)
    [1] => Homer Jay Simpson
    [2] => homer
)
php > preg_match('#\[@([^\]]+)\]\(id:([^)]+)\)#', $str, $matches);print_r($matches);