JavaScript Regular Expressions 2

Question 1

What does the `*` quantifier mean in a regular expression?

Accepted Answer

Zero or more occurrences of the preceding token

Answer

One or more occurrences of the preceding token

Answer

Zero or one occurrence of the preceding token

Answer

Exactly one occurrence of the preceding token

Question 2

When `String.prototype.match()` is called with a regex that has the `g` flag, what does it return?

Accepted Answer

An array containing all matched substrings

Answer

A single match object with index and groups

Answer

A boolean indicating whether a match was found

Answer

The index of the first match

Question 3

What does the syntax `(?:...)` create in a regular expression?

Accepted Answer

A non-capturing group that groups tokens without saving the match

Answer

A named capturing group

Answer

A positive lookahead assertion

Answer

A positive lookbehind assertion

Question 4

What does `\b` represent in a regular expression?

Accepted Answer

A word boundary between a word character and a non-word character

Answer

A literal backspace character

Answer

The beginning of the string

Answer

Any blank (whitespace) character

Question 5

What does `RegExp.prototype.exec(str)` return when the pattern matches?

Accepted Answer

An array containing the full match and any captured groups, with index and input properties

Answer

Only the matched substring as a plain string

Answer

A boolean true value

Answer

An array of all matches in the string

Question 6

What does the quantifier `{2,5}` mean in a regular expression?

Accepted Answer

Matches between 2 and 5 occurrences of the preceding token

Answer

Matches exactly 2 or exactly 5 occurrences

Answer

Matches at least 2 but no maximum

Answer

Matches 2 through 5 different characters

Question 7

What does the character class `[^abc]` match?

Accepted Answer

Any single character that is NOT a, b, or c

Answer

The literal characters a, b, and c in sequence

Answer

Any character at the start of the string

Answer

The literal string '^abc'