What I've done today is Strip Comments in JavaScript.

Regex is awesome!

CodeWars

Problem

Strip Comments

Complete the solution so that it strips all text that follows any of a set of comment markers passed in. Any whitespace at the end of the line should also be stripped out.

Example:

Given an input string of:

apples, pears # and bananas
grapes
bananas !apples

The output expected would be:

apples, pears
grapes
bananas

The code would be called like so:

var result = solution("apples, pears # and bananas\ngrapes\nbananas !apples", ["#", "!"])
// result should == "apples, pears\ngrapes\nbananas"

Solution

const escape = (string) => string.replace(/[-\/\\^$*+?.()|[\]{}]/g, '\\$&');

function solution(input, markers) {
  if (input[input.length-1] !== "\n") input += "\n";
  markers.map(m => escape(m)).forEach(m => input = input.replace(RegExp(`\ *${m}.*?\n`), "\n"));
  return input.slice(0,-1);
};

////

function solution(input, markers){
  return input.replace(RegExp("\\s?[" + markers.join("") + "].*(\\n)?", "gi"), "$1");
}

////

function solution(input, markers) {
  return input.split('\n').map(
    line => markers.reduce(
      (line, marker) => line.split(marker)[0].trim(), line
    )
  ).join('\n')
}