Podcast
Questions and Answers
What is the purpose of the \b anchor in regular expressions?
What is the purpose of the \b anchor in regular expressions?
What does the [a-g] pattern match in regular expressions?
What does the [a-g] pattern match in regular expressions?
What is the purpose of a non-capturing group in regular expressions?
What is the purpose of a non-capturing group in regular expressions?
What does the \W pattern match in regular expressions?
What does the \W pattern match in regular expressions?
Signup and view all the answers
What is the purpose of the a{1,3} quantifier in regular expressions?
What is the purpose of the a{1,3} quantifier in regular expressions?
Signup and view all the answers
Study Notes
Character Classes
- Any character except newline:
\w,\d,\smatch word, digit, whitespace respectively - Not word, digit, whitespace:
\W,\D,\Srespectively - Match any of a, b, or c:
[abc] - Not a, b, or c:
[^abc] - Character between a & g:
[a-g]
Anchors
- Start of the string:
^ - End of the string:
$ - Word boundary:
\b - Not-word boundary:
\B
Escaped Characters
- Escaped special characters:
\.,\\ - Tab, linefeed, carriage return:
\t,\n,\r
Groups & Lookaround
- Capture group:
(abc) - Backreference to group #1:
\1 - Non-capturing group:
(?:abc) - Positive lookahead:
(?=abc) - Negative lookahead:
(?!abc)
Quantifiers & Alternation
- 0 or more, 1 or more, 0 or 1:
a*,a+,a? - Exactly five, two or more:
a{5},a{2,} - Between one & three:
a{1,3} - Match as few as possible:
a+?,a{2,}? - Match ab or cd:
ab|cd
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Description
Understanding character classes, anchors, escaped characters, groups, and lookaround in regular expressions. Learn about pattern matching techniques in programming.
