Regular expression (regex)

A regular expression (regex) is a sequence of characters that defines a search pattern, often used for pattern matching within strings. It’s commonly used in text processing to find, replace, or validate strings based on certain patterns.

Examples:

• Basic Pattern Matching:some text
  • Regex: cat
  • Matches: “The cat is on the mat.” (finds the word “cat” in the text)
• Wildcard Character (.):some text
  • Regex: c.t
  • Matches: “The cat”, “cut”, or “cot” (any character between ‘c’ and ‘t’).
• Digit Matching (\d):some text
  • Regex: \d{3}
  • Matches: “There are 123 apples.” (matches any sequence of three digits)

Regular expressions allow you to create flexible patterns to handle diverse text search and validation needs. Learn more.