Note: information on this page refers to Ceylon 1.0, not to the current release.

String literals

A literal notation for a String value.

Usage

A String literal is written between paired double quotes:

String example = "This is a trivial example";
String escaping = "\"Escaping\" with a backslash";
String multiline = "Strings may
                    span lines";// note indentation, see below

A verbatim String literal is written between paired triple-double quotes:

String verbatim = """<p>"Almost, but not quite, entirely unlike tea."</p>"""

Description

Escaping

Plain string literals may contain escape sequences. Backslash is used as an escape character. The following characters must be escaped when they're used within a plain String literal:

  • backslash, \, must be written as \\
  • double quote, ", must be written as \"
  • backtick, `, must be written as \`

In a plain String literal, the following traditional C-style escape sequences are also supported:

  • tab, \t
  • newline, \n
  • return, \r
  • form feed, \f
  • backspace, \b
  • single quote, \'

In contrast, verbatim String literals do not support any escaping, so you can use characters like ", \, and ` freely, with their literal interpretation.

Unicode characters

You can use the same unicode escapes within plain string literals as in Character literals. Like this:

String quotation = "I think, \{#2234} I am"; // Unicode therefore symbol

Or using the Unicode character name:

String quotation = "I think, \{THEREFORE} I am";

Of course, you can also directly embed a Unicode character in a String literal:

String quotation = "I think, ∴ I am";

But this is highly discouraged, since it causes problems when sharing source code across operating systems with different default character encodings.

Line spanning

String literals may span lines. A line break in a string literal always results in a (Unix-style) newline character in the resulting String, irrespective of the platform-specific character used to encode the end of line in the source file itself.

For example, a multiline string in a source file which uses \r\n as line separator (the Windows convention) will be compiled to a string which uses \n as line separator.

If a different convention is really required, use escaping instead of line spanning literals.

Every line of a string literal spanning multiple lines is understood to begin at the same column. Leading whitespace is automatically stripped from the resulting String. For example:

String greeting = "Hello
                   World";

And:

String greeting = """Hello
                     World""";

Are both exactly equivalent to:

String greeting = "Hello\nWorld";

Interpolation

Plain strings containing two backticks, ``, are not considered literal strings, but string templates.

Verbatim strings do not support interpolation.

See also