====== Identifiers ======

An identifier is a string of letters, numbers, and underscores (_), used to name and identify following entities:

  * [[:en:mervis-ide:35-help:035-software_basic:030-common-elements:035-constant|constants]]
  * [[:en:mervis-ide:35-help:035-software_basic:030-common-elements:030-variables|variables]]
  * [[:en:mervis-ide:35-help:035-software_basic:035-data-types:015-user_defined_data_types|derived data types]]
  * [[:en:mervis-ide:35-help:035-software_basic:045-pou:|functions, function blocks, and programs]]
  * [[:en:mervis-ide:35-help:015-plc:065-plc_prog_map|tasks]]

A identifier must begin with a letter or underscore and must not contain spaces. National characters (accented characters) are not allowed in identifiers. Upper/lower case is not relevant.\\


Example:

<code st-iec>
IW215, QX75, IDENT, LIM_SW_5, abcd, ab_cd, _MAIN, _12V7
</code>