PHP regex，preg_replace_callback，在1个字符串中失败，有2个可能的匹配

I was playing around with this very basic class to learn more about regexes. What I wanted to achieve is to grab the content from a testview file, grab the string exactly between {{EACH slides}} and {{#EACH}}. The regex now present in the class did just that, plus the variable name in the opening tag. I then wanted to use that string to loop it with the right variable and put it back in place.I was playing around with this very basic class