Supported Metacharacters
Ruby supports the metacharacters and metasequences listed in Table 32 through Table 37. For expanded definitions of each metacharacter, see "Regex Metacharacters, Modes, and Constructs.â
Table 1-32. Ruby character representations
Sequence | Meaning |
---|---|
| Alert (bell), |
| Backspace, |
| ESC character, |
| Newline, |
| Carriage return, |
| Form feed, |
| Horizontal tab, |
| Vertical tab, |
| Character specified by a two-digit octal code. |
| Character specified by a two-digit hexadecimal code. |
| Named control character. |
Table 1-33. Ruby character classes and class-like constructs
Class | Meaning |
---|---|
| A single character listed, or contained within a listed range. |
| A single character not listed, and not contained within a listed range. |
| Any character, except a line terminator (unless single-line mode, |
| Word character. |
| Nonword character. |
| Digit. |
| Nondigit. |
| Whitespace character, |
| Nonwhitespace character, |
Table 1-34. Ruby anchors and other zero-width tests
Sequence | Meaning |
---|---|
| Start of string, or the point after any newline. |
| Beginning of string, in all match modes. |
| End of string, or the point before any newline. |
| End of string, but before any final line terminator, in all match modes. |
| End of string, in all match modes. |
| Boundary between a |
| Not-word-boundary. |
| End of the previous match. |
| Positive lookahead. |
| Negative lookahead. ... |
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