The String.raw tag function can be used with template literals to access a version of their contents without interpreting any backslash escape sequences.
String.raw`\n` will contain a backslash and the lowercase letter n, while `\n` or '\n' would contain a single newline character instead.
const patternString = String.raw`Welcome, (\w+)!`;
const pattern = new RegExp(patternString);
const message = "Welcome, John!";
pattern.exec(message);
["Welcome, John!", "John"]