Regular Expression: Difference between revisions

Revision as of 17:33, 23 January 2026

Symbol	Name	Meaning	Example	Matches
Literals
(text)	Literal	Matches exact text	`cat`	"cat"
Wildcards & Classes
`.`	Dot	Matches any single character	`h.t`	"hat", "hot"
`[ ]`	Brackets	List of allowed characters	`b[ai]t`	"bat", "bit"
`[^ ]`	Negation	Matches anything NOT in the list	`[^a]`	Any char except 'a'
Quantifiers
`*`	Star	0 or more times	`go*d`	"gd", "god", "good"
`+`	Plus	1 or more times	`go+d`	"god", "good"
`?`	Question	0 or 1 time (Optional)	`colou?r`	"color", "colour"
Anchors
`^`	Caret	Start of string	`^The`	"The end"
`$`	Dollar	End of string	`end$`	"The end"
Special Characters
`\`	Escape	Treats special characters as text	`\.`	"." (actual dot)
`\`	Escape	Treats special characters as text	`\$`	"$" (actual dollar)
`\d`	Digit	Any number 0-9	`\d\d`	"42", "99"
`\w`	Word	Letter, number, or underscore	`\w+`	"Hello_1"
`\s`	Space	Whitespace (space, tab, enter)	`A\sB`	"A B"

@@ Line 33: / Line 33: @@
 |-
 | <code>\</code> || Escape || Treats special characters as text || <code>\.</code> || "." (actual dot)
+|-
+| <code>\</code> || Escape || Treats special characters as text || <code>\$</code> || "$" (actual dollar)
 |-
 | <code>\d</code> || Digit || Any number 0-9 || <code>\d\d</code> || "42", "99"