Search results
Results from the WOW.Com Content Network
In the C++ programming language, argument-dependent lookup (ADL), or argument-dependent name lookup, [1] applies to the lookup of an unqualified function name depending on the types of the arguments given to the function call. This behavior is also known as Koenig lookup, as it is often attributed to Andrew Koenig, though he is not its inventor ...
The following is a declaration of the concept "equality_comparable" from the <concepts> header of a C++20 standard library. This concept is satisfied by any type T such that for lvalues a and b of type T, the expressions a==b and a!=b as well as the reverse b==a and b!=a compile, and their results are convertible to a type that satisfies the concept "boolean-testable":
The term concept (and its popularization) is credited to Alexander Stepanov, [2] [3] the primary designer of the STL. In the C++ 1998 standard, the Concept term was introduced to name just a simple description of the requirements for particular type, usually being a template parameter. It was not encoded in the language explicitly – the ...
If the object type is known, this may be bypassed by prepending a fully qualified class name before the function call, but in general calls to virtual functions are resolved at run time. In addition to standard member functions, operator overloads and destructors can be virtual.
C++ generally prohibits forward references, but they are allowed in the special case of class members. Since the member function accessor cannot be compiled until the compiler knows the type of the member variable myValue, it is the compiler's responsibility to remember the definition of accessor until it sees myValue's declaration.
The initial proposal to the C++ standards committee outlined a combination of the two variants; the operator would return a reference type only if the declared type of the expression included a reference. To emphasize that the deduced type would reflect the "declared type" of the expression, the operator was proposed to be named decltype. [2]
A name used in a template declaration or definition and that is dependent on a template-parameter is assumed not to name a type unless the applicable name lookup finds a type name or the name is qualified by the keyword typename. In short, if the compiler can't tell if a dependent name is a value or a type, then it will assume that it is a value.
Function names are mangled by default in Rust. However, this can be disabled by the #[no_mangle] function attribute. This attribute can be used to export functions to C, C++, or Objective-C. [9] Further, along with the #[start] function attribute or the #[no_main] crate attribute, it allows the user to define a C-style entry point for the ...