Need RegExp.flags

[jmagaram]

I have a regular expression. I want to check if it starts with ^ and if not, create a new regular expression with ^ at the beginning. Like this...

  let patternMustStart = pattern => {
    let original = pattern->RegExp.source
    switch original->String.startsWith("^") {
      | true => pattern
      | false => RegExp.fromStringWithFlags("^"++original, ~flags=Js.Re.flags(pattern))
  }

The RegExp.flags function is missing. Must use Js.Re instead.