Quotes and Interpolation
Perl uses customary quotes to construct strings and such, but also implements a generic quoting mechanism. For example, the string 'Hello!' can be written as q/Hello!/, q;Hello!;, q{Hello!}, and so on.
Customary | Generic | Meaning | Inter. | Page |
|---|---|---|---|---|
|
| Literal string | No | |
|
| Literal string | Yes | |
|
| Command execution | Yes | |
|
| Word list | No | |
|
| Regular expression | Yes | |
|
| Pattern match | Yes | |
|
| Pattern substitution | Yes | |
|
| Character translation | No |
When the quoting mechanism involves delimiters, you can use pairs of grouping characters, e.g., m< . . . > and s{ ... }[ ... ].
The “Inter.” column of the table on the preceding page indicates whether string escape sequences are interpolated. If single quotes are used as delimiters for pattern matching or substitution, no interpolation takes place.
String escape sequences:
| Alarm (bell). |
| Backspace. |
| Escape. |
| Formfeed. |
| Newline. |
| Return. |
| Tab. |
Combining prefixes construct characters, for example:
\53Interpreted as octal, the character
+. Octal escapes take up to three octal digits, including leading zeros. The resulting value must not exceed 377 octal. In patterns, which are like qq// strings, leading zeros are mandatory in octal escapes to avoid interpretation as a back-reference unless the value exceeds the number of captures or 9, whichever is lower. Note that if it’s a back-reference, the value is interpreted as decimal, not as octal.\cCInterpreted as a control character: Control-C.
\N{BLACK SPADE SUIT}A named character: ...