Question

Having trouble with a regular expression (they are not my strong suit). I’m trying to match all strings between {{ and }}, but if a set of brackets occurs on the same line, it counts that as a single match… Example:

$string = "
  Hello, kind sir
  {{SHOULD_MATCH1}} {{SHOULD_MATCH2}}
  welcome to
  {{SHOULD_MATCH3}}
  ";

preg_match_all("/{{(.*)}}/", $string, $matches);

var_dump($matches); // returns arrays with 2 results instead of 3

returns:

array(2) {
  [0]=>
  array(2) {
    [0]=>
    string(35) "{{SHOULD_MATCH1}} {{SHOULD_MATCH2}}"
    [1]=>
    string(17) "{{SHOULD_MATCH3}}"
  }
  [1]=>
  array(2) {
    [0]=>
    string(31) "SHOULD_MATCH1}} {{SHOULD_MATCH2"
    [1]=>
    string(13) "SHOULD_MATCH3"
  }
}

Any help? Thanks!

Answer 1

Replace the * quantifier with its non-greedy form *?.

This will make it match as little as possible while still allowing the expression to match as a whole, which is different from its current behavior of matching as much as possible.