RELAX NG

Chapter 18. Compact Syntax Reference

This reference follows the formal description of the compact syntax described as an EBNF (Extended Backus-Naur Form, a syntax that doesn’t include annotation syntax) grammar. Each definition of the EBNF grammar is documented. When a definition includes a long list of alternatives (as is the case for pattern, nameClass, and literalSegment), each alternative is documented separately. The grammar from the specification has been slightly simplified to suppress definitions that were used only once; nevertheless, the meaning has been kept unchanged.

Here is the full EBNF grammar that’s used as the basis for this reference:

topLevel                ::= 
decl* (
pattern|
grammarContent*)
decl                    ::= "namespace" 
identifierOrKeyword        "=" 
namespaceURILiteral
                        |"default" "namespace" [
identifierOrKeyword]       "=" 
namespaceURILiteral
                        |"datatypes" 
identifierOrKeyword        "=" 
literal
pattern                 ::= "element" 
nameClass "{" 
pattern "}"
                        |"attribute" 
nameClass "{" 
pattern "}"
                        |
pattern ("," 
pattern)+
                        |
pattern ("&" 
pattern)+
                        |
pattern ("|" 
pattern)+
                        |
pattern "?"
                        |
pattern "*"
                        |
pattern "+"
                        |"list" "{" 
pattern "}"
                        |"mixed" "{" 
pattern "}"
                        |
identifier
                        |"parent" 
identifier
                        |"empty"
                        |"text"
                        |[
datatypeName] 
literal
                        |
datatypeName ["{" 
param* "}"] [
exceptPattern]
                        |"notAllowed"
                        |"external" 
literal [
inherit]
                        |"grammar" "{" 
grammarContent* "}"
                        |"(" 
pattern ")"
param               ::= 
identifierOrKeyword "=" 
literal
exceptPattern       ::= "-" 
pattern
grammarContent      ::= 
start
                        |
define
                        |"div" "{" 
grammarContent* "}" |"include" ...