OpenSearch/docs/painless/painless-identifiers.asciidoc

[[painless-identifiers]]
=== Identifiers

Use an identifier as a named token to specify a
<<painless-variables, variable>>, <<painless-types, type>>,
<<dot-operator, field>>, <<dot-operator, method>>, or function.
<<painless-keywords, Keywords>> cannot be used as identifiers.

*Grammar*
[source,ANTLR4]
----
ID: [_a-zA-Z] [_a-zA-Z-0-9]*;
----

*Examples*

* Variations of identifiers.
+
[source,Painless]
----
a
Z
id
list
list0
MAP25
_map25
Map_25
----
Painless: Docs Clean Up (#29592) As part of the lang spec: separated identifiers into its own section, and cleaned up variables section. 2018-04-25 09:38:41 -07:00			`[[painless-identifiers]]`
			`=== Identifiers`

Painless: Types Section Clean Up (#30283) Clean up of types section, casting section, and a large number of examples. 2018-05-23 13:36:58 -07:00			`Use an identifier as a named token to specify a`
			`<<painless-variables, variable>>, <<painless-types, type>>,`
			`<<dot-operator, field>>, <<dot-operator, method>>, or function.`
			`<<painless-keywords, Keywords>> cannot be used as identifiers.`
Painless: Docs Clean Up (#29592) As part of the lang spec: separated identifiers into its own section, and cleaned up variables section. 2018-04-25 09:38:41 -07:00
			`Grammar`
			`[source,ANTLR4]`
			`----`
			`ID: [_a-zA-Z] [_a-zA-Z-0-9]*;`
			`----`

			`Examples`

			`* Variations of identifiers.`
			`+`
			`[source,Painless]`
			`----`
			`a`
			`Z`
			`id`
			`list`
			`list0`
			`MAP25`
			`_map25`
			`Map_25`
			`----`