Hi Folks, I think it is mind-blowing when a language is defined using the language itself. This document defines the XML Schema language using XML Schema: http://www.w3.org/TR/xmlschema11-1/#normative-schemaSchema That is the XML schema-for-schemas! This document defines the JSON Schema language using JSON Schema: http://json-schema.org/draft-04/schema# That is the JSON schema-for-schemas! These two documents define the ANTLR grammar language using the ANTLR grammar: https://github.com/antlr/grammars-v4/blob/master/antlr4/ANTLRv4Parser.g4 https://github.com/antlr/grammars-v4/blob/master/antlr4/ANTLRv4Lexer.g4 That is the ANTLR grammar-for-grammars! Neat! Do you know of other languages that are defined using the language itself? /Roger _______________________________________________________________________ XML-DEV is a publicly archived, unmoderated list hosted by OASIS to support XML implementation and development. To minimize spam in the archives, you must subscribe before posting. [Un]Subscribe/change address: http://www.oasis-open.org/mlmanage/ Or unsubscribe: xml-dev-unsubscribe@lists.xml.org subscribe: xml-dev-subscribe@lists.xml.org List archive: http://lists.xml.org/archives/xml-dev/ List Guidelines: http://www.oasis-open.org/maillists/guidelines.php