Initialization (programming)

In <a href="/facts/Computer_programming/QmSsFnu0">computer programming</a>, initialization or initialisation is the <a href="/facts/Assignment_(computer_science)/kLevAoyJ">assignment</a> of an initial value for a <a href="/facts/Data_object/eX99dtAw">data object</a> or variable. The manner in which initialization is performed depends on the <a href="/facts/Programming_language/cWTYbgWa">programming language</a>, as well as the type, storage class, etc., of an object to be initialized. Programming constructs which perform initialization are typically called initializers and initializer lists. Initialization is distinct from (and preceded by) <a href="/facts/Declaration_(computer_programming)/CbH6UjHA">declaration</a>, although the two can sometimes be conflated in practice. The complement of initialization is <a href="/facts/Finalization/6vU0SvEb">finalization</a>, which is primarily used for objects, but not variables.
Initialization is done either by statically embedding the value at compile time, or else by assignment at <a href="/facts/Run_time_(program_lifecycle_phase)/lCxKsrzB">run time</a>. A section of code that performs such initialization is generally known as "initialization code" and may include other, one-time-only, functions such as opening files; in <a href="/facts/Object-oriented_programming/TxNMEcao">object-oriented programming</a>, initialization code may be part of a <a href="/facts/Constructor_(object-oriented_programming)/8JNHsH5H">constructor</a> (class method) or an initializer (instance method). Setting a memory location to <a href="/facts/Hexadecimal/02ohQW22">hexadecimal</a> zeroes is also sometimes known as "clearing" and is often performed by an <a href="/facts/Exclusive_or/FHyr7hGQ">exclusive or</a> instruction (both operands specifying the same variable), at <a href="/facts/Machine_code/bgdQ1Fxf">machine code</a> level, since it requires no additional memory access.

Initialization (programming) open-in-new

Initialization (programming)