2.13.4-[lex.string]-"lexical. String"

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2 Lexical conventions [Lex] 2.13 Literals [lex.literal] 2.13.4 String literals [lex.string]	2 lexical contract "lexical" 2.13 literal Amount "lexical. Amount of text" 2.13.4 string literal amount "lexical. String"
string-literal:         "S-char-sequenceopt"         L "s-char-sequenceopt"     s-char-sequence:          S-char         s-char-sequence S-char     S-char:         Any member of the source character set Except             the Double-quote ", backslash/, or New-line character         escape-sequence          universal-character-name	String-text amount:         "s-character-sequence opt"          L "s-character-sequence opt"     S-character-sequence:          S-character         S-character-sequence S-character     S-character:          any member in the source character set, except              double quote ", backslash/, or newline character         escape-sequence          Unified character name
A string literal is a sequence of characters (as defined in 2.13.2) surrounded by double quotes, optionally beginning With the letter L, as in "..." or L "...". A string literal that does not begin with a ordinary string literal, also referred to as a narrow string literal. An ordinary string literal have type "array of n const char" and static storage duration (3.7), where n is the size of the string as defined below, and is initialized with the given characters. A string literal that begins with L, such as L "ASDF", is a wide string literal. A wide string literal has type "array of n const wchar_t" and have static storage duration, where n is the size of the Stri ng as defined below, and is initialized with the given characters.	String literals are enclosed in double quotes and may consist of a sequence of characters (defined in 2.13.2) that begins with a letter L, such as "..." Or L "...". String literals that are not started by L are normal string literals and are also known as narrow string literals. The normal string literal has an array of type "N const char" and a static storage type (3.7), where n is the length of the string defined below and initialized by the given character. A string starting with L, such as L "ASDF", is a wide string literal. The wide string literal has an array of type "N const wchar_t" and a static storage type, where n represents the length of a string as defined below and is initialized by the given character.
Whether all string literals was distinct (that's, is stored in nonoverlapping objects) is implementation-defined. The effect of attempting to modify a string literal is undefined.	Whether to keep all string literals independent (that is, stored in objects that are not overlapped) is defined by the compiler. The effect of trying to modify the amount of a string literal is undefined.
In translation phase 6 (2.1), adjacent narrow string literals is concatenated and adjacent wide string literals is Conca Tenated. If a narrow string literal token is adjacent to a wide string literal token, the behavior is undefined. Characters in concatenated strings is kept distinct. [Example: "/xa" "B" Contains the characters '/xa ' and ' B ' after concatenation (and not the a single hexadecimal character '/xab '). ]	In the 6th stage of translation (2.1), adjacent narrow string literals are concatenated, and adjacent wide string literals are concatenated. If a narrow string literal tag is adjacent to a wide string literal token, its behavior is undefined. The characters in the concatenated string exist independently. Cases "/xa" "B" After the connection will contain two characters '/xa ' and ' B ' (instead of a single hexadecimal character '/xab '). 】
After any necessary concatenation, in translation Phase 7 (2.1), '/0 ' are appended to every string literal so that programs That scan a string can find its end.	In the 7th stage (2.1), after the necessary connection, '/0 ' is added to each string literal, allowing the program to scan the string to find its end.
Escape sequences and universal-character-names in string literals has the same meaning as in character literals (2.13 .2), except that the single quote ' was representable either by itself or by the escape sequence/', and the double quote " Shall is preceded by A/. In a narrow string literal, a universal-character-name could map to more than one char element due to multibyte encoding. The size of a wide string literal is the total number of escape sequences, universal-character-names, and other characters , plus one for the terminating L '/0 '. The size of a narrow string literal is the total number of escape sequences and other characters, plus at least one for th e multibyte encoding of each universal-character-name, plus one for the terminating '/0 '.	Escape sequences and uniform character names in string literals have the same meaning as in the amount of character literals (2.13.2), except that the single quote ' can represent itself, or be escaped from the sequence/' represented, and the double quote ' must be a/start. In a narrow string literal, a uniform character name may be mapped to more than one char element by multi-byte encoding. The length of the wide string literal is the total number of escape sequences, uniform character names, and other characters, plus a trailing character of L '/0 '. The length of the narrow string literal is the escape sequence and other characters, plus at least one byte number of multibyte encodings per uniform character name, plus a trailing character '/0 '.
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