Regex

Question 1

Anchors — what do they do?

Answer 1

Anchors do not match any character at all. Instead, they match a position before, after, or between characters.

source: https://www.regular-expressions.info/anchors.html

Question 2

*

Answer 2

Quantifier: 0 or more

Question 3

+

Answer 3

Quantifier: 1 or more

Question 4

?

Answer 4

Quantifier: 0 or 1

Can also be added to another quantifier to make it ungreedy

Question 5

{3}

Answer 5

Quantifier: Exactly 3

Question 6

{3,}

Answer 6

Quantifier: 3 or more

Question 7

{3,5}

Answer 7

Quantifier: 3, 4, or 5

Answer 8

Anchor: Start of string, or start of line in a multi-line pattern

Question 9

\A

Answer 9

Anchor: Start of string

Question 10

$

Answer 10

Anchor: End of string, or end of line in multi-line pattern

Question 11

\Z

Answer 11

Anchor: End of string

Question 12

\b

Answer 12

Anchor: Word boundary

Question 13

\B

Answer 13

Anchor: Not word boundary

Question 14

\⋜

Answer 14

Anchor: Start of word

Question 15

>

Answer 15

Anchor: End of word

Question 16

Three positions that count as word boundaries

Answer 16

• Before the first character in the string, if the first character is a word character.
• After the last character in the string, if the last character is a word character.
• Between two characters in the string, where one is a word character and the other is not a word character.

Source: https://www.regular-expressions.info/wordboundaries.html

Question 17

\c

Answer 17

Character Class: Control character

Question 18

\s

Answer 18

Character class: white space

Question 19

\S

Answer 19

Character class: Not white space

Question 20

\d

Answer 20

Character class: digit

Question 21

\D

Answer 21

character class: Not digit

Question 22

\w

Answer 22

Character class: word

Question 22

\w

Answer 22

Character class: \w

Question 23

\W

Answer 23

Character class: Not word

Question 24

\x

Answer 24

Character class: Hexadecimal digit

Question 25

\O

Answer 25

Character class: octal digit