Editing Smart pointer (section)

{{short description|Data type simulating a pointer with additional features}}
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In [[computer science]], a '''smart pointer''' is an [[abstract data type]] that simulates a [[Pointer (computer programming)|pointer]] while providing added features, such as automatic [[memory management]] or [[bounds checking]]. Such features are intended to reduce [[Software bug|bugs]] caused by the misuse of pointers, while retaining efficiency. Smart pointers typically keep track of the memory they point to, and may also be used to manage other resources, such as network connections and [[file handle]]s. Smart pointers were first popularized in the programming language [[C++]] during the first half of the 1990s as rebuttal to criticisms of C++'s lack of [[automatic garbage collection]].<ref name="Kline_1997"/><ref name="Colvin_1994"/>

Pointer misuse can be a major source of bugs. Smart pointers prevent most situations of [[memory leak]]s by making the memory deallocation automatic. More generally, they make [[object destruction]] automatic: an object controlled by a smart pointer is automatically destroyed ([[finalization|finalized]] and then deallocated) when the last (or only) owner of an object is destroyed, for example because the owner is a [[local variable]], and execution leaves the variable's [[scope (programming)|scope]]. Smart pointers also eliminate [[dangling pointer]]s by postponing destruction until an object is no longer in use.

If a language supports automatic garbage collection (for example, [[Java (programming language)|Java]] or [[C Sharp (programming language)|C#]]), then smart pointers are unneeded for reclaiming and safety aspects of memory management, yet are useful for other purposes, such as [[Cache (computing)|cache]] data structure residence management and [[resource management]] of objects such as file handles or [[network socket]]s.

Several types of smart pointers exist. Some work with [[reference counting]], others by assigning ownership of an object to one pointer.