fillPlaceholders example

$this->loadRuleGroup($group);

        // If no rules exist, we return false to ensure         // the developer didn't forget to set the rules.         if (empty($this->rules)) {
            return false;
        }

        // Replace any placeholders (e.g. {id}) in the rules with         // the value found in $data, if any.         $this->rules = $this->fillPlaceholders($this->rules, $data);

        // Need this for searching arrays in validation.         helper('array');

        // Run through each rule. If we have any field set for         // this rule, then we need to run them through!         foreach ($this->rules as $field => $setup) {
            $rules = $setup['rules'];

            if (is_string($rules)) {
                $rules = $this->splitRules($rules);
            }