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In computer science, primitive data type is either of the following: * a ''basic type'' is a data type provided by a programming language as a basic building block. Most languages allow more complicated ''composite types'' to be recursively constructed starting from basic types. * a ''built-in type'' is a data type for which the programming language provides built-in support. In most programming languages, all basic data types are built-in. In addition, many languages also provide a set of composite data types. Opinions vary as to whether a built-in type that is not basic should be considered "primitive". Depending on the language and its implementation, primitive data types may or may not have a one-to-one correspondence with objects in the computer's memory. However, one usually expects operations on basic primitive data types to be the fastest language constructs there are. Integer addition, for example, can be performed as a single machine instruction, and some processors offer specific instructions to process sequences of characters with a single instruction. In particular, the C standard mentions that "a int is likely to be 32 bits long on a 32-bit architecture. Basic primitive types are almost always value types.Most languages do not allow the behavior or capabilities of primitive (either built-in or basic) data types to be modified by programs. Exceptions include Smalltalk, which permits all data types to be extended within a program, adding to the operations that can be performed on them or even redefining the built-in operations. ==Overview== The actual range of primitive data types that is available is dependent upon the specific programming language that is being used. For example, in C, strings are a composite but built-in data type, whereas in modern dialects of BASIC and in JavaScript, they are assimilated to a primitive data type that is both basic and built-in. Classic basic primitive types may include: * Character ( character, char);* Integer ( integer, int, short, long, byte) with a variety of precisions;* Floating-point number ( float, double, real, double precision);* Fixed-point number ( fixed) with a variety of precisions and a programmer-selected scale.* Boolean, logical values true and false. * Reference (also called a ''pointer'' or ''handle''), a small value referring to another object's address in memory, possibly a much larger one. More sophisticated types which can be built-in include: * Tuple in ML, Python * List in Lisp * Complex number in Fortran, C (C99), Lisp, Python, Perl 6, D * Rational number in Lisp, Perl 6 * Associative array in various guises, in Lisp, Perl, Python, Lua, D * First-class function, closure, continuation in languages that support functional programming such as Lisp, ML, Perl 6, D and C# 3.0 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Primitive data type」の詳細全文を読む スポンサード リンク
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