# This file is part of TagSoup and is Copyright 2002-2008 by John Cowan.
#
# TagSoup is licensed under the Apache License,
# Version 2.0.  You may obtain a copy of this license at
# http://www.apache.org/licenses/LICENSE-2.0 .  You may also have
# additional legal rights not granted by this license.
#
# TagSoup is distributed in the hope that it will be useful, but
# unless required by applicable law or agreed to in writing, TagSoup
# is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS
# OF ANY KIND, either express or implied; not even the implied warranty
# of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

default namespace = "http://www.ccil.org/~cowan/XML/tagsoup/tssl"

start = schema

## A TSSL schema has a namespace, which is applied to the elements by default,
## and a name, which is used solely for documentation.  It contains entity
## definitions, a root element, and attributes to be applied to all elements.
schema = element schema {
		attribute ns {xsd:anyURI},
		attribute prefix {xsd:NCName},
		attribute name {xsd:NCName},
		attribute version {"1.0"},
		entity*,
		group+,
		\element,
		\attribute*
		}

## An entity has a name and a Unicode codepoint in hex.
entity = element entity {
		attribute name {xsd:NCName},
		attribute codepoint {xsd:string}
		}

## A group is a named group of elements.  Every element belongs to one
## or more groups and has a content model consisting of one or more groups.
group = element group {
	attribute id {xsd:ID}
	}

## An element has a name and a namespace (currently ignored).
## It can have any of several types of content and can be restartable
## or not.  The element is also a member of one or more model groups
## (with arbitrary names), and can contain as children zero or more
## model groups.  Elements also have attributes and "natural" children.
\element = element element {
		attribute ns {xsd:anyURI}?,
		attribute name {xsd:NCName},
		attribute type {type},
		attribute closeMode { "unclosable" | "restartable" }?,
		attribute text-parent { "true" | "false" }?,
		(element memberOf { attribute group {xsd:IDREF}}+ |
		 element isRoot { empty} |
		 element memberOfAny { empty }),
		element contains { attribute group {xsd:IDREF}}*,
		\attribute*,
		\element*
		}

## Here are the attribute types:

type = "element" | "any" | "empty" | "mixed" | "string" | "cdata"

## An attribute has a name and a namespace (currently not supported).
## It also has an optional type and an optional default value.
\attribute = element attribute {
	attribute ns {xsd:anyURI}?,
	attribute name {xsd:NCName},
	attribute type {"ID" | "IDREF" | "IDREFS" | "NMTOKEN" | "BOOLEAN"}?,
	attribute default {xsd:string}?
	}