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character literal

character literal

Syntax

' c-char '(1)
u8 ' c-char '(2)(since C++17)
u ' c-char '(3)(since C++11)
U ' c-char '(4)(since C++11)
L ' c-char '(5)
' c-char-sequence '(6)

where.

  • c-char is either

1) narrow character literal or ordinary character literal, e.g. 'a' or '\n' or '\13'. Such literal has type char and the value equal to the representation of c-char in the execution character set. If c-char is not representable as a single byte in the execution character set, the literal has type int and implementation-defined value

2) UTF-8 character literal, e.g. u8'a'. Such literal has type char and the value equal to ISO 10646 code point value of c-char, provided that the code point value is representable with a single UTF-8 code unit. If c-char is not in Basic Latin or C0 Controls Unicode block, the program is ill-formed.

3) UCS-2 character literal, e.g. u'貓', but not u'?' (u'\U0001f34c'). Such literal has type char16_t and the value equal to the value of c-char in Unicode, if it is a part of the basic multilingual plane. If c-char is not part of the BMP, the program is ill-formed.

4) UCS-4 character literal, e.g. U'貓' or U'?'. Such literal has type char32_t and the value equal to the value of c-char in Unicode.

5) wide character literal, e.g. L'β' or L'貓'. Such literal has type wchar_t and the value equal to the value of c-char in the execution wide character set. If c-char is not representable in the execution character set (e.g. a non-BMP value on Windows where wchar_t is 16-bit), the value of the literal is implementation-defined.

6) Multicharacter literal, e.g. 'AB', has type int and implementation-defined value.

Notes

Many implementations of multicharacter literals use the values of each char in the literal to initialize successive bytes of the resulting integer, in big-endian order, e.g. the value of '\1\2\3\4' is 0x01020304.

In C, character constants such as 'a' or '\n' have type int, rather than char.

See also

| C documentation for character constant |

|:----|

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