Regex – get everything between two characters based on input

let assume I have string like:
"Today is ((day|12pm))"

what I would like to do now is to get everything between (()) for substring "day" but without the brackets. So the result would be: day|12pm but for another substring like time ((time|moon)) would return time|moon.

I could only came up with something like this:
\(\(\W*day – it gets me ((day which is only part of the string. How to get the other part till )) but without the brackets itself?

Thanks.

>Solution :

The regex in JavaScript would look like this

const regex = /\(\(([^)]*)\)\)/

The actual code would be like this

const inputString = "Today is ((day|12pm))";
const regex = /\(\(([^)]*)\)\)/;
const matches = inputString.match(regex);
console.log(matches)

if (matches && matches.length > 1) {
  const result = matches[1];
  console.log(result); // Output: day|12pm
} else {
  console.log("No match found");
}

As matches is containing the array of values. If there is a match then matches[1] extracts the content captured