Identifier

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An identifier (rarely identifier , English identifier ) is in the computer science an identifier that allows a programmer in a program an object such. B. uniquely names a data type , a variable or a function . An identifier must therefore be unique within a namespace , unless the programming language allows overloading .

As a rule, literals (made up of letters ) are used for identifiers. Also numerals (from numbers ) are common, but can not be good mnemonic , this is achieved with a combination of a string of letters and numbers. Prefixes or suffixes are often used for type identification .

Programming languages ​​use different conventions for identifiers, e.g. B. which (special) characters may appear in it, whether a distinction is made between upper and lower case and the maximum length of the identifier. In addition, more extensive naming rules can be applied, some of which are publicly defined (for example in Hungarian notation ) or which have been established as a company standard regarding the programming style .

Examples

  • frm_Kunddaten: Identifier (also called 'Name') for a form in a 4GL development language; alternatively z. B. 'Customer data_frm'
  • ZwFeld_RechnSumme: Identifier for a data field in which the sums of the invoices add up.
  • Rechnen_MWST: Identifier for an algorithm ( procedure or similar) for calculating the value added tax (sales tax)

See also