Topics

• Lookahead and Lookbehind
• Match Reset: \K
• Anchor Characters: Dollar ($)
• Character classes
• Regex modifiers (flags)

Examples

• Simulating variable-length lookbehind with \K
• Search and replace using \K operator
• Match a letter at the end of a line or string
• Non-alphanumerics matching (negated character class)
• Character class and common problems faced by beginner
• DOTALL modifier
• MULTILINE modifier
• IGNORE CASE modifier
• VERBOSE / COMMENT / IgnorePatternWhitespace modifier
• Explicit Capture modifier
• UNICODE modifier
• PCRE_DOLLAR_ENDONLY modifier
• PCRE_ANCHORED modifier
• PCRE_UNGREEDY modifier
• PCRE_INFO_JCHANGED modifier
• PCRE_EXTRA modifier