Anchors allow a match to succeed or fail depending on the current position in the string. The following table lists the anchors:
| Assertion | Description | Pattern | Matches |
|---|---|---|---|
| ^ | The match must start at the beginning of the string or line. | ^\d{3} | "567" in "567-777-" |
| $ | The match must occur at the end of the string or before \n at the end of the line or string. | -\d{4}$ | "-2012" in "8-12-2012" |
| \A | The match must occur at the start of the string. | \A\w{3} | "Code" in "Code-007-" |
| \Z | The match must occur at the end of the string or before \n at the end of the string. | -\d{3}\Z | "-007" in "Bond-901-007" |
| \z | The match must occur at the end of the string. | -\d{3}\z | "-333" in "-901-333" |
| \G | The match must occur at the point where the previous match ended. | \\G\(\d\) | "(1)", "(3)", "(5)" in "(1)(3)(5)[7](9)" |
| \b | The match must occur on a boundary between a \w (alphanumeric) and a\W(nonalphanumeric) character. | \w | "R", "o", "m" and "1" in "Room#1" |
| \B | The match must not occur on a \bboundary. | \Bend\w*\b | "ends", "ender" in "end sends endure lender" |
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