Identifiers (IDs) are lexical Token (parser)s that name entities. The concept is analogy to that of a "name". Identifiers are used extensively in virtually all information processing systems. Naming entities makes it possible to refer to them, which is essential for any kind of processing. == Identifiers in computer languages == In computer languages, identifiers are textual Token (parser)s (also called symbols) which name language entities. In programming languages, examples of such entities are variables, datatypes, labels, subroutines, packages, etc. Computer languages usually place restrictions on what an identifier may look like. For example, in C Plus Plus, one restriction is that identifiers must be composed of letters, digits, and underscores. In compiled programming languages, identifiers are compile time entities. That is, at runtime the compiled program operates in terms of memory addresses and offsets, and the textual identifier tokens are no longer present or used. In interpreted languages identifiers often ''are'' available at runtime, sometimes even as first-class objects which can be freely manipulated and evaluated. Compilers and interpreters usually do not attach meaning to the actual identifier chosen for an entity, as long as it is unique within a certain context. However, there are exceptions. For example: * in Ruby programming language a variable is automatically considered immutable if its identifier starts with a capital letter; * in Fortran, the first letter in a variable's name indicates whether by default it is created as an integer or floating point variable. == See also == * keywords (reserved identifiers with special meaning) * overloading#Overloading * naming conventions (programming) * name binding Identifiers
Move from Name and identifier to Identifier? Motivation: This article really only discusses identifiers. "Name and identifier" is plain silly. -- User:Eelis.net 02:42, 2005 May 23 (UTC) : User:Violetriga User_talk:violetriga 10:35, 28 May 2005 (UTC) ----- I made the following changes: * "Language object" was awkward. * List of example language entities was.. unusual. * "Token" is more accurate than "lexical unit" (which didn't have an article anyway). * Description of "label" made very little sense and was probably associated with a specific language. * Computer languages is more accurate than programming languages (think markup languages). * We don't need to define "keyword", there's a separate article for that. * Made the C++ identifier example a bit simpler, we don't need full detail here. * Opening statement should aim to define. Usage is secondary. * Usage remark should be as broad as possible: information processing systems. * Examples of what we can identify in general is impossible. We can identify _anything_ we can model. * The identifiers in telecommunications and data processing section really didn't add anything to the general definition. * I've moved the naming conventions section to a new article: naming conventions (programming). * The "to be merged" section didn't describe identifiers. * The reference to the federal standard didn't add anything. -- User:Eelis.net 23:34, 2005 May 22 (UTC)
See other meanings of words starting from letter:
Words begining with Identifier:
Identifier
Identifier
Identifiers
Identifiers
Identifier_naming_convention
Identifier
Identifiers (IDs) are lexical Token (parser)s that name entities. The concept is analogy to that of a "name". Identifiers are used extensively in virtually all information processing systems. Naming entities makes it possible to refer to them, which is essential for any kind of processing. == Identifiers in computer languages == In computer languages, identifiers are textual Token (parser)s (also called symbols) which name language entities. In programming languages, examples of such entities are variables, datatypes, labels, subroutines, packages, etc. Computer languages usually place restrictions on what an identifier may look like. For example, in C Plus Plus, one restriction is that identifiers must be composed of letters, digits, and underscores. In compiled programming languages, identifiers are compile time entities. That is, at runtime the compiled program operates in terms of memory addresses and offsets, and the textual identifier tokens are no longer present or used. In interpreted languages identifiers often ''are'' available at runtime, sometimes even as first-class objects which can be freely manipulated and evaluated. Compilers and interpreters usually do not attach meaning to the actual identifier chosen for an entity, as long as it is unique within a certain context. However, there are exceptions. For example: * in Ruby programming language a variable is automatically considered immutable if its identifier starts with a capital letter; * in Fortran, the first letter in a variable's name indicates whether by default it is created as an integer or floating point variable. == See also == * keywords (reserved identifiers with special meaning) * overloading#Overloading * naming conventions (programming) * name binding Identifiers
Identifier
Move from Name and identifier to Identifier? Motivation: This article really only discusses identifiers. "Name and identifier" is plain silly. -- User:Eelis.net 02:42, 2005 May 23 (UTC) : User:Violetriga User_talk:violetriga 10:35, 28 May 2005 (UTC) ----- I made the following changes: * "Language object" was awkward. * List of example language entities was.. unusual. * "Token" is more accurate than "lexical unit" (which didn't have an article anyway). * Description of "label" made very little sense and was probably associated with a specific language. * Computer languages is more accurate than programming languages (think markup languages). * We don't need to define "keyword", there's a separate article for that. * Made the C++ identifier example a bit simpler, we don't need full detail here. * Opening statement should aim to define. Usage is secondary. * Usage remark should be as broad as possible: information processing systems. * Examples of what we can identify in general is impossible. We can identify _anything_ we can model. * The identifiers in telecommunications and data processing section really didn't add anything to the general definition. * I've moved the naming conventions section to a new article: naming conventions (programming). * The "to be merged" section didn't describe identifiers. * The reference to the federal standard didn't add anything. -- User:Eelis.net 23:34, 2005 May 22 (UTC)
See other meanings of words starting from letter:
I
IA | IB | IC | ID | IE | IF | IG | IH | IJ | IK | IL | IM | IN | IO | IP | IR | IS | IT | IU | IW | IX | IY | IZ |Words begining with Identifier:
Identifier
Identifier
Identifiers
Identifiers
Identifier_naming_convention
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