Search results
Results from the WOW.Com Content Network
C# provides type-safe object-oriented function pointers in the form of delegates. class Program { // Delegate type: delegate int Operation ( int a , int b ); static int Add ( int i1 , int i2 ) { return i1 + i2 ; } static int Sub ( int i1 , int i2 ) { return i1 - i2 ; } static void Main () { // Instantiate the delegate and assign the method to it.
List comprehension is a syntactic construct available in some programming languages for creating a list based on existing lists. It follows the form of the mathematical set-builder notation (set comprehension) as distinct from the use of map and filter functions.
The GroupBy operator takes a function that extracts a key value and returns a collection of IGrouping<Key, Values> objects, for each distinct key value. The IGrouping objects can then be used to enumerate all the objects for a particular key value. Distinct The Distinct operator removes duplicate instances of an object from a collection.
Boxing is the operation of converting a value-type object into a value of a corresponding reference type. [108] Boxing in C# is implicit. Unboxing is the operation of converting a value of a reference type (previously boxed) into a value of a value type. [108] Unboxing in C# requires an explicit type cast. A boxed object of type T can only be ...
In computer programming, a function object [a] is a construct allowing an object to be invoked or called as if it were an ordinary function, usually with the same syntax (a function parameter that can also be a function). In some languages, particularly C++, function objects are often called functors (not related to the functional programming ...
Objects may be accessed directly, by a language loop construct (e.g. for loop) or with an iterator. An associative container uses an associative array, map, or dictionary, composed of key-value pairs, such that each key appears at most once in the container. The key is used to find the value, the object, if it is stored in the container.
Typically a generic function is an instance of a class that inherits both from function and standard-object. Thus generic functions are both functions (that can be called with and applied to arguments) and ordinary objects. The book The Art of the Metaobject Protocol explains the implementation and use of CLOS generic functions in detail.
Unlike a real unit type which is a singleton, the void type lacks a way to represent its value and the language does not provide any way to declare an object or represent a value with type void. In the earliest versions of C, functions with no specific result defaulted to a return type of int and functions with no arguments simply had empty ...