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The std::string class is the standard representation for a text string since C++98. The class provides some typical string operations like comparison, concatenation, find and replace, and a function for obtaining substrings. An std::string can be constructed from a C-style string, and a C-style string can also be obtained from one. [7]
Most of the functions that operate on C strings are declared in the string.h header (cstring in C++), while functions that operate on C wide strings are declared in the wchar.h header (cwchar in C++). These headers also contain declarations of functions used for handling memory buffers; the name is thus something of a misnomer.
C lacks built-in string or array assignment, so the string is not being transferred to p, but rather p is being made to point to the constant string in memory. In Pascal, unlike C, the string's first character element is at index 1 and not 0 (leading it to be length-prefixed). This is because Pascal stores the length of the string at the 0th ...
For function that manipulate strings, modern object-oriented languages, like C# and Java have immutable strings and return a copy (in newly allocated dynamic memory), while others, like C manipulate the original string unless the programmer copies data to a new string.
In C, declaring a new type with the same name as an existing struct, union or enum is valid, but it is invalid in C++, because in C, struct, union, and enum types must be indicated as such whenever the type is referenced whereas in C++, all declarations of such types carry the typedef implicitly.
[98] [99] [100] However, the C++11 standard introduces new incompatibilities, such as disallowing assignment of a string literal to a character pointer, which remains valid C. To intermix C and C++ code, any function declaration or definition that is to be called from/used both in C and C++ must be declared with C linkage by placing it within ...
But it comes with a performance penalty for string literals, as std::string usually allocates memory dynamically, and must copy the C-style string literal to it at run time. Before C++11, there was no literal for C++ strings (C++11 allows "this is a C++ string"s with the s at the end of the literal), so the normal constructor syntax was used ...
C's string-literal syntax has been very influential, and has made its way into many other languages, such as C++, Objective-C, Perl, Python, PHP, Java, JavaScript, C#, and Ruby. Nowadays, almost all new languages adopt or build upon C-style string syntax. Languages that lack this syntax tend to precede C.