Search results
Results from the WOW.Com Content Network
For example, in C, int const x = 1; declares an object x of int const type – the const is part of the type, as if it were parsed "(int const) x" – while in Ada, X: constant INTEGER:= 1_ declares a constant (a kind of object) X of INTEGER type: the constant is part of the object, but not part of the type. This has two subtle results.
Conversely, the mutable keyword allows a class member to be changed even if an object was instantiated as const. Even functions can be const in C++. The meaning here is that only a const function may be called for an object instantiated as const; a const function doesn't change any non-mutable data. C# has both a const and a readonly qualifier ...
Copy constructors are the standard way of copying objects in C++, as opposed to cloning, and have C++-specific nuances. The first argument of such a constructor is a reference to an object of the same type as is being constructed (const or non-const), which might be followed by parameters of any type (all having default values).
The same distinction holds for comparing objects for equality: most basically there is a difference between identity (same object) and equality (same value), corresponding to shallow equality and (1 level) deep equality of two object references, but then further whether equality means comparing only the fields of the object in question or ...
Addition is a binary operation, which means it has two operands.In C++, the arguments being passed are the operands, and the temp object is the returned value.. The operation could also be defined as a class method, replacing lhs by the hidden this argument; However, this forces the left operand to be of type Time:
/*Ruby has three member variable types: class, class instance, and instance. */ class Dog # The class variable is defined within the class body with two at-signs # and describes data about all Dogs *and* their derived Dog breeds (if any) @@sniffs = true end mutt = Dog. new mutt. class. sniffs #=> true class Poodle < Dog # The "class instance variable" is defined within the class body with a ...
Statement separator – demarcates the boundary between two statements; need needed for the last statement Line continuation – escapes a newline to continue a statement on the next line Some languages define a special character as a terminator while some, called line-oriented , rely on the newline .
C++11 extended this further, to make classes act identically to POD objects in many more cases. ^c pair only ^d Although Perl doesn't have records, because Perl's type system allows different data types to be in an array, "hashes" (associative arrays) that don't have a variable index would effectively be the same as records.