Source: https://stackoverflow.com/questions/27019696/regex-to-match-specific-functions-and-their-arguments-in-files

lookahead

Wyciąga treść z nagłówków h2.

this should cover all USA cities with special characters as per https://en.wikipedia.org/wiki/List_of_U.S._cities_with_diacritics

This regex takes a function declaration and transforms it to an arrow function. Replace: const $1 = $2 => $3;

this will exclude particular phrase from a line. means it will match only those line which dont have those word

Extracting temperature measurements from txt file

Same temperature measurement extraction example but this time using grouping such that we can choose only the positive measurements before September 10