Question

I’m struggling to find the best way to do this. Basically I am provided strings that are like this with the task of printing out the string with the math parsed.

Jack has a [0.8*100]% chance of passing the test. Katie has a [(0.25 + 0.1)*100]% chance.

The mathematical equations are always encapsulated by square brackets. Why I’m dealing with strings like this is a long story, but I’d really appreciate the help!

Answer 1

preg_match_all('/\[(.*?)\]/', $string, $out);
foreach ($out[1] as $k => $v)
{
    eval("\$result = $v;");
    $string = str_replace($out[0][$k], $result, $string);
}

This code is highly dangerous if the strings are user inputs because it allows any arbitrary code to be executed