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This was recognized as a defect in the standard and fixed in C++.) [4] C++11 and C11 add two types with explicit widths char16_t and char32_t. [5] Variable-width encodings can be used in both byte strings and wide strings. String length and offsets are measured in bytes or wchar_t, not in "characters", which can be confusing to beginning ...
The std::string type is the main string datatype in standard C++ since 1998, but it was not always part of C++. From C, C++ inherited the convention of using null-terminated strings that are handled by a pointer to their first element, and a library of functions that manipulate such strings.
"The width of wchar_t is compiler-specific and can be as small as 8 bits. Consequently, programs that need to be portable across any C or C++ compiler should not use wchar_t for storing Unicode text. The wchar_t type is intended for storing compiler-defined wide characters, which may be Unicode characters in some compilers." [6]
For example, the four character string "I♥NY" is encoded in UTF-8 like this (shown as hexadecimal byte values): 49 E2 99 A5 4E 59. Of the six units in that sequence, 49, 4E, and 59 are singletons (for I, N, and Y ), E2 is a lead unit and 99 and A5 are trail units.
%I2 indicates an integer of width 2 (the order of the format specification's field width and type is reversed compared to C's printf); %I5 indicates an integer of width 5; *N is a BCPL language escape sequence representing a newline character (for which C uses the escape sequence \n ).
A common alternative to wchar_t is to use a variable-width encoding, whereby a logical character may extend over multiple positions of the string. Variable-width strings may be encoded into literals verbatim, at the risk of confusing the compiler, or using numerical backslash escapes (e.g. "\xc3\xa9" for "é" in UTF-8).
C++11 allows raw strings, unicode strings (UTF-8, UTF-16, and UTF-32), and wide character strings, determined by prefixes. It also adds literals for the existing C++ string, which is generally preferred to the existing C-style strings. In Tcl, brace-delimited strings are literal, while quote-delimited strings have escaping and interpolation.
The standard variable [2] can be formed as fixed data such as a Boolean, Integer or Decimal and a variable length variable such as an ASCII string, wide character string or a binary string. The type of the data can be used to define variable or the type can be explicitly declared, so for example the code - variable myInteger = 0; will create a ...