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Changes between Initial Version and Version 1 of echo-schema/usage-guide

Timestamp:: Jul 19, 2011, 2:59:52 PM (13 years ago)
Author:: Wolfgang Schmidle
Comment:: --

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echo-schema/usage-guide

                       v1
+[[PageOutline(1-4,,pullout)]]
+[wiki:echo-schema ECHO-Schema], [wiki:echo-schema/overview 1. Überblick], [wiki:echo-schema/usage-guide 2. Usage Guide], [wiki:echo-schema/implementation 3. Umsetzung]
+== 2. Usage Guide
+Eine erste Version des Usage Guide für das Schema: [source:trunk/papers/documentation/usage_guide.pdf PDF]
+(Stand April 2010; TO DO: aus LaTeX in das Wiki übertragen, aktualisieren)
+=== General
+Design decisions:
+  *  one schema for all texts
+  * modules should be independent
+  * tags in the DESpecs should have some counterpart in the Schema, if possible
+  * however, do not mimic the DESpecs structure
+Standard suffixes as in xhtml:
+  * .attrib (defined in echo-attribute)
+  * .datatype (defined in echo-datatype)
+  * .model (defined in echo-content)
+  * .class (defined in several modules)
+IDs are expected, but XML texts should also validate without IDs
+=== Informationsquellen und minimales Schema
+Der Kern des Schemas:
+"(--)" bedeutet: nicht minimal, aber man bekommt etwas dafür, was über die optische Anzeige des Textes hinausgeht
+|| Ebene || minimal || China || Modul || Element  ||
+|| || || || || ||
+|| Grobstruktur || + || -- || echo-start || <echo>  ||
+|| || + || -- || echo-metadata || <metadata>  ||
+|| || +/-- || -- || echo-metadata || Metadaten  ||
+|| || + || -- || echo-div || <text> ||
+|| || || || || ||
+|| Mittelstruktur || (--) || + || echo-div || <div index>, <div toc>  ||
+||  || (--) || -- || echo-div || <div chapter> etc. ||
+|| || || || || ||
+|| Feinstruktur || + || + || echo-block || <head>, <p>, <note>  ||
+|| || + || -- || echo-block || <s>  ||
+|| || -- || + || echo-block-scholarly || <quote>  ||
+|| || -- || -- || echo-block-scholarly || <set-off> ||
+|| || || || || ||
+|| Text || -- || + || echo-content || <emph>  ||
+|| || (--) || -- || echo-content || <reg> ||
+|| || (--) || -- || echo-content-scholarly || <foreign>, <ref> ||
+|| || -- || -- || echo-content-scholarly || <sic>, <set-off>, <q> ||
+|| || || || || ||
+|| Hilfsmodule || + || n/a || echo-attribute || --  ||
+||  || + || n/a || echo-datatype || -- ||
+|| || || || || ||
+|| F: Figures || -- || + || echo-figure || <figure>, <caption> etc. ||
+|| F: Handwritten || -- || + || echo-handwritten || <handwritten> ||
+|| F: Chinese text || -- || + || echo-chinese-text || <head ti>, <p @indent>, <p @ics>, <pb @ics>  ||
+|| F: Textflows || -- || + || echo-textflows || <head @flow>, <p @flow>, <div multiflow @flows>  ||
+|| F: Tables || -- || + || echo-import-xhtml || <xhtml:table>  ||
+|| F: Lists || -- || -- || echo-import-xhtml || <xhtml:ul> etc. ||
+|| F: Floats || -- || -- || echo-float || <div float> ||
+|| F: Images || -- || -- || echo-figure || <image> ||
+|| || || || || ||
+|| T: Milestones || (--) || + || echo-milestone || <pb> (auch F), <lb>, <cb> ||
+|| T: Corruptions || -- || + || echo-gap || <gap>, <unsure>  ||
+|| || -- || + || echo-de || <de:unknown>, <de:wrong> ||
+|| T: Chinese notes || -- || + || echo-chinese-text || <lb halfline> ||
+|| T: Floats || -- || + || echo-float || <anchor> ||
+|| T: numbers etc. || (--) || -- || echo-mathematics || <num>, <var> ||
+|| T: formulas || (--) || -- || echo-import-mathml || <mml:math> ||
+|| T: Verse || -- || -- || echo-textflows || <lb @label> ||
+|| T: Images || -- || -- || echo-figure || <image> ||
+|| T: Gis || -- || -- || echo-gis || <place>, <time> ||
+|| || || || || ||
+|| G: Gis || -- || -- || echo-gis || <dcterms:temporal>, <dcterms:spatial> ||
+=== Übersicht über die Module
+ * [source:trunk/schema/schema/echo/echo-echo.rnc echo] ist die Haupt-Datei des Schemas. Hier werden alle Module geladen.
+ * [source:trunk/schema/schema/echo/modules/echo-echo-start.rnc echo-start], [source:trunk/schema/schema/echo/modules/echo-echo-metadata.rnc echo-metadata], [source:trunk/schema/schema/echo/modules/echo-echo-div.rnc echo-div], [source:trunk/schema/schema/echo/modules/echo-echo-block.rnc echo-block], [source:trunk/schema/schema/echo/modules/echo-echo-block-scholarly.rnc echo-block-scholarly] definieren die Struktur des XML-Dokuments bis vom root element `<echo>` bis zum Text-Level:
+{{{
+<echo>               echo-start.rnc
+    <metadata>       echo-metadata.rnc
+    <text>           echo-div.rnc
+        <div>           - " -
+            <head>   echo-block.rnc
+            <p>         - " -
+                <s>     - " -
+            <note>      - " -
+}}}
+  * [source:trunk/schema/schema/echo/modules/echo-echo-start.rnc echo-start]: Zum root element <echo> gibt es kein Gegenstück in den DESpecs. Es muss in das Dokument eingefügt werden.
+  * [source:trunk/schema/schema/echo/modules/echo-echo-metadata.rnc echo-metadata]: Zu <metadata> und allen darin enthaltenen Metadaten gibt es kein Gegenstück in den DESpecs. <metadata> und einige Metadaten sind notwendig und müssen in das Dokument eingefügt werden. Andere Metadaten sind optional.
+  * [source:trunk/schema/schema/echo/modules/echo-echo-div.rnc echo-div]: Zu <text> und <div> gibt es ebenfalls kein Gegenstück in den DESpecs. <text> ist notwendig und muss in das Dokument eingefügt werden. <div> kann weggelassen werden.
+  * [source:trunk/schema/schema/echo/modules/echo-echo-block.rnc echo-block], [source:trunk/schema/schema/echo/modules/echo-echo-block-scholarly.rnc echo-block-scholarly]: <head> und <p> haben direkte Gegenstücke in den DESpecs. <note> hat die Gegenstücke <mgl>, <mgr> und <fn>. Das Element <s> hat kein Gegenstück in den DESpecs. Es muss aber in das Dokument eingefügt werden, um das Dokument valide zu machen.
+ * [source:trunk/schema/schema/echo/modules/echo-echo-content.rnc echo-content],  [source:trunk/schema/schema/echo/modules/echo-echo-content-scholarly.rnc echo-content-scholarly] definieren das Inline-Modell für Text. Der Text muss nicht weiter ausgezeichnet werden, um ein valides Dokument zu haben.
+ * [source:trunk/schema/schema/echo/modules/echo-echo-attribute.rnc echo-attribute], [source:trunk/schema/schema/echo/modules/echo-echo-datatype.rnc echo-datatype] definieren Standard-Attribute und -Datentypen. Sie werden von allen Modulen verwendet.
+ * [source:trunk/schema/schema/echo/modules/echo-echo-gap.rnc echo-gap], [source:trunk/schema/schema/echo/modules/echo-echo-de.rnc echo-de]
+ * [source:trunk/schema/schema/echo/modules/echo-echo-figure.rnc echo-figure]
+ * [source:trunk/schema/schema/echo/modules/echo-echo-handwritten.rnc echo-handwritten]
+ * [source:trunk/schema/schema/echo/modules/echo-echo-milestone.rnc echo-milestone]
+ * [source:trunk/schema/schema/echo/modules/echo-echo-float.rnc echo-float]
+ * [source:trunk/schema/schema/echo/modules/echo-echo-mathematics.rnc echo-mathematics]
+ * [source:trunk/schema/schema/echo/modules/echo-echo-chinese-text.rnc echo-chinese-text]
+ * [source:trunk/schema/schema/echo/modules/echo-echo-gis.rnc echo-gis]
+ * [source:trunk/schema/schema/echo/modules/echo-echo-textflows.rnc echo-textflows]
+ * [source:trunk/schema/schema/echo/xhtml/echo-echo-import-xhtml.rnc echo-import-xhtml]
+ * [source:trunk/schema/schema/echo/modules/echo-echo-import-mathml.rnc echo-import-mathml]
+=== echo-start
+<text>: The default type is "free".
+=== echo-metadata
+[source:trunk/schema/schema/echo/modules/echo-echo-metadata.rnc echo-metadata]: There is no counterpart of the metadata in the DESpecs.
+==== dcterms
+ * <dcterms:identifier>
+Bibliographisch:
+ * <dcterms:title> +, <dcterms:alternative> *
+   * <dcterms:alternative> refines <dcterms:title>
+ * <dcterms:creator> +, <dcterms:contributor> *
+  * <dcterms:creator> refines <dcterms:contributor>
+ * <dcterms:publisher> *
+ * <dcterms:language>+
+ * <dcterms:date> ?
+ * <dcterms:description> *
+Lizenz:
+ * <dcterms:rights> *, <dcterms:license> *, <dcterms:accessRights>
+  * <dcterms:license> may be text or a URI.
+  * <dcterms:license> and <dcterms:accessRights> refine <dcterms:rights>
+ * <dcterms:rightsHolder> *
+ * <dcterms:provenance> *
+ * <dcterms:dateCopyrighted> ?
+  * <dcterms:dateCopyrighted> refines <dcterms:date>
+Dabei meint + "mindestens einmal", * "beliebig oft", ? "höchstens einmal". Ohne Symbol heißt "genau einmal". Verpflichtend sind also:
+ * <dcterms:identifier>
+ * <dcterms:title>
+ * <dcterms:creator>
+ * <dcterms:language>
+ * <dcterms:accessRights>
+Zu "refines": creator refines contributor, d.h. ein creator ist automatisch auch ein contributor; aber ein contributor ist nicht unbedingt ein creator. Anders gesagt: A refines B heißt, A ist eine Teilmenge von B. Anderes Beispiel: Eiche refines Baum.
+==== other metadata
+ * <font>, <font-family>
+  * echo.font-families <-- "song style" in echo-chinese-text
+ * <echolink>, <echodir>
+In general, there is no counterpart for <text> or <div> in the DESpecs.
+=== echo-div
+DESpecs nach Schema:
+ * <ind> --> <div type="index">
+ * <toc> --> <div type="toc">
+ * other types:
+  * if the type is in the standard list: type="definition" type-free="界"
+  * if it is not in the standard list:   type="other" type-free="界/definition"
+Liste aller div-Typen, die auf besondere Weise behandelt werden:
+ * u.a. float
+ * aber auch multiflow, parallel; chapter, section; ...
+=== echo-block
+ * Headings: <head>
+  * <h> --> <head>
+ * Semantic units: <s>
+  * (<s> is not in the raw text)
+ * Floating objects in <s> (all <note>, <handwritten>, <table>; most <figure>; some <math>) are replaced by <anchor> and moved to a <div type="float"> directly behind the <p>. The new <div type="float"> contains all <note>, <handwritten>, <figure>, <table>, <math> that have been moved in this <div>.
+ * Notes: <note>
+  * <mgl> --> <anchor type="note"/>, <note position="left">
+  * <mgr> --> <anchor type="note"/>, <note position="right">
+  * echo.note.content = echo.flexible.model to allow for different kinds of notes
+=== echo-block-scholarly
+ * <set-off>
+=== echo-content
+Most elements in this module have no counterpart in the Specs and will be added in the post-processing stage.
+==== <emph>
+<emph> for emphasis (should be used only when something is not tagged otherwise)
+The tags `_ _` (for italics), `<bf>`, `<sc>`, `<_>`, `<^>`, `<ul>`, `<ol>`, `<st>`, `<red>`, `<sp>` in the Specs are normally represented by <emph style="...">. The tags can be combined, e.g. <emph style="it bf"> for bold italics. For a whole <s> or <p>, the style attribute is there (or even higher in the hierarchy).
+==== <reg>
+Only the original text is regularized using echo.reg; typing conventions and additional typos in the transcription are silently resolved.
+list of typing conventions in the DESpecs which are silently resolved:
+ * `$` --> ſ
+ * `\'q`  --> q + combining diacritic (U+0300 etc.) and normalization form C, for example q̀
+ * ...
+examples:
+{{{
+<reg orig="ĳs" type="lig">ijs</reg>
+<reg orig="sphęrae" type="simple">sphaerae</reg>
+<reg orig="sphęrae">sphaerae</reg>
+<reg orig="sphę rae" type="simple">sphae<lb/>rae</reg>
+<reg orig="eiuſdẽ" type="context">eiuſdem</reg>
+<reg orig="eſsẽt" type="context">eſsent</reg>
+<reg orig="lib." type="context">liber</reg>
+in <reg orig="lib." type="context">libro</reg>
+<reg orig="qñ" type="wordlist">quando</reg>
+<reg orig="tm̃" type="wordlist/context">tamen</reg>
+<reg orig="tm̃" type="wordlist/context">tantum</reg>
+<reg orig="Arist." type="unresolved">Arist.</reg>
+<reg orig="inrerrogas" type="typo" resp="paul">interrogas</reg>
+<reg orig="quem" type="conjecture" resp="paul">quam</reg>
+<reg orig="re ferre" type="conjecture" resp="paul">re<lb/>ferre</reg>
+<reg orig="ꝑꝑ" type="unknown">ꝑꝑ</reg>
+<reg orig="ꝑꝑ" type="conjecture" resp="paul">prope</reg>
+}}}
+note:
+  * the default type is "simple", e.g. <reg orig="sphęrae">sphaerae</reg>
+   * Beispiel veraltet!
+   * Beachte: der type kann zurzeit nicht weggelassen werden, und das ist auch gut so, falls man nämlich die <reg> automatisiert nachbearbeiten muss.
+  * the first exampe ijs applies only if `ĳ` is not silently resolved
+  * missing hyphens are indicated by a soft hyphen "" rather than <reg>; however, you may use "conjecture" in non-trivial cases
+  * the generic "abbr" may be used for any abbreviation
+  * abbreviations are not resolved within <ref>, e.g.  ex <ref id="N400238">.19. lib. quinti Eu-<lb/>clid.</ref> (wirklich?)
+==== Text-Modelle
+Avoiding Recursions: Wie ist die Inline-model-Hierarchie?
+  * inline anfangen können:  s head caption description variables, evtl. note handwritten xhtml
+  * in inline, und Inhalt inline (mit Rekursionsgefahr): s-set-off, ref, foreign, emph, q
+  * in inline, und Inhalt plaintext: reg, sic, num, var, place, time
+  * in inline, und inhalt es selbst: mml.math
+  * in plaintext, und Inhalt plaintext: gibt es nicht
+  * in plaintext, Inhalt text: unsure (Inhalt in plaintext ändern?)
+  * in plaintext, leer: milestones, anchor, gap, unknown, wrong
+Schematron-Regel, die Rekursionen aufspürt, d.h.
+ * z.B. <ref> in <ref>
+ * z.B.  <ref> in <foreign> in  ... in <ref>
+also zusammen: kein Element aus dieser Gruppe darf sich sich selbst als ancestor haben.
+=== echo-content-scholarly
+ * <ref>
+ * <sic> for mistakes in the original text:
+  * o<!>  -->  o<de:wrong/>  -->  <sic comment="n missing">o</sic> (see the discussion in echo-de)
+ * <foreign>: Foreign text is not marked in the transcription, i.e. <foreign> cannot be inserted automatedly without additional linguistic knowledge.
+  * Exception: <rom>sentence</rom> --> <foreign xml:lang="la">sentence</foreign> with language "la" as a first guess, and similarly in Chinese text.
+  * (echo.foreign has echo.core.attrib, but echo.language.attrib is obligatory)
+ * Quotations:
+  * <q> is for short inline quotes. Note that echo.delimiter-attrib is optional; however, please use it if possible
+  * <quote> (echo.quote) for longer inline quotes (one-sentence quote are <quote><s>Sentence.</s></quote> and not <s><q>Sentence.</q></s>)
+  *  <quote> (echo.blockquote) for blockquotes
+  * Es kann keine Rekursionen von quote-Elementen geben.
+=== echo-gap
+ * @@    --> <gap extent="2"/>
+ * <gap> --> <gap/>
+ * x< ? > --> x<unsure/> or <unsure>x</unsure> (this can not be fully automated)
+=== echo-de
+This module contains tags from the DESpecs that will be removed in the course of processing. We use the namespace "de" for the corresponding elements in the xml:
+ * <001> --> <de:unknown code="001"/> (bzw. wir haben eine Tabelle, was gemeint ist)
+ * <!>   --> <de:wrong/> --> remove or <sic>
+=== echo-figure
+ * <fig> --> <figure>, eventuell mit <anchor/>
+ * <cap> --> <caption>
+ * <desc> --> <description>
+ * <var> --> <variables>
+=== echo-handwritten
+In its simplest form, <handwritten> is just an empty tag. Nonetheless, within <s> it is replaced by <anchor> and moved to <div type="float"> to cater for scholarly additions, i.e. it is part of echo.float.class and not of echo.inline.class
+ * <hd> --> <handwritten/>, eventuell mit <anchor/>
+=== echo-float
+=== echo-milestone
+==== line breaks
+[Dieser Abschnitt ist sicher veraltet!]
+<lb/> can be in plaintext (<s>, <head>, some <note>, all members of echo.inline.class) and <p>
+in <p>: since a paragraph is split into <s>, most line breaks are actually in <s>. However:
+ * <lb/></s><s> and </s><s><lb/> shouldn't occur (--> </s><lb/><s> [and space before </s>?])
+ * <lb/></s></p> shouldn't occur at all
+in <s> (and similarly for <head> and the members of echo.inline.class):
+ * line break --> <lb/>; no space before <lb/>; no line break after <lb/>; space after <lb/> if there is a hyphen before <lb/> (no automated space if the hyphen is missing)
+examples:
+ * <s>亦<lb/>能使人無疑。</s>
+ * <note>Plutar <lb/>chus in <lb/>commẽ <lb/>tario de <lb/>dæmo-<lb/>nio So-<lb/>cratis.</note>
+We use the normal hyphen U+002D instead of the soft hyphen U+00AD because the soft hyphen is not displayed in the xhtml. --> ?
+==== column breaks
+ * <col 1>...</col><col 2>...</col>  -->  ...<cb/>...
+==== page breaks
+[Dieser Abschnitt ist sicher veraltet!]
+<pb/> can occur wherever <lb/> occurs (although it will be rare in <head>), and <div>
+ * <pb vii><rh>xyz</rh> --> <pb n="10" o="vii" o-norm="7" rhead="xyz" xlink:href="URI"/>
+ * <pb 一六七a>  --> <pb n="..." o="一六七a" o-norm="167a" xlink:href="URI"/>
+=== echo-attribute
+In echo-attribute werden Standard-Attribute definiert.
+Text-Eigenschaften:
+ * echo.language.attrib (@xml:lang)
+ * echo.style.attrib (@style):
+   * direkt in: <text>; <emph>, <num>, <var>, <w>, <place>, <time>, <person>
+   * via echo.core.attrib in: <div>, <p>, <quote>, <note>, <handwritten>, <entry>; <reg>, <foreign>, <ref>, <q>
+   * via echo.inline.attrib in: <head>, <s>, <caption>, <description>, <variables>, <form>, <translation>, <pronunciation>
+   * in xhtml:* als @class
+ * echo.id.attrib (@xml:id)
+ * echo.core.attrib fasst echo.language.attrib, echo.style.attrib und echo.id.attrib zusammen
+ * echo.space.attrib (@xml:space="preserve")
+ * echo.inline.attrib ist echo.core.attrib plus echo.space.attrib
+Div-Attribute:
+ * echo.n.attrib (@n)
+ * echo.level.attrib (@level)
+Notes:
+ * echo.symbol.attrib (@symbol)
+Links:
+ * echo.file.attrib (@file)
+ * echo.internal-link.attrib (@xlink:href, @xlink:label, @xlink:type)
+ * echo.external-link.attrib (@xlink:href)
+Zitate:
+ * echo.delimiter.attrib (@open, @close)
+=== echo-datatype
+=== echo-mathematics
+ * number <num>:
+  * "vii" --> <num value="7">vii</num>
+  * "½"   --> <num value="0.5">½</num>
+ * variable <var>:
+  * "AB" --> <var type="line">AB</var> (type ist optional)
+Eine Funktion von <num> und <var> ist es, den Inhalt vor der morphologischen Analyse zu verstecken.
+Note: The scope of echo.num and echo.var is very limited. More complex mathematics is expressed with MathML --> echo-import-mathml
+=== echo-chinese-text
+ * <ti> --> <head type="ti">
+ * indentations in Chinese text:
+  * <p ii> --> <p indent="2char"> oder nur "2"?
+  * <p xx> --> <p indent="-2char">
+  * (indent is deliberately not defined as style="valid css" because it may be semantically meaningful)
+ * Linien:
+  * <sl> --> <emph style="sl">
+  * <dl> --> <emph style="dl">
+  * <wl> --> <emph style="wl">
+  * <cl> --> <emph style="cl">
+Small text:
+ * in <p>:  <sm>  --> <small>
+ * everywhere else: <emph style="sm"> (<h>, rhead, <ti>, <toc>, etc.)
+ * `\\` --> <smlb/>
+(plus some manual corrections where this simple distinction doesn't fit, e.g. <sm>chen</sm>)
+=== echo-gis
+Note: this module is still experimental.
+Beachte in diesem Modul definierte Metadaten
+=== echo-textflows
+@flow is normally a number, or "footnote"
+=== echo-import-xhtml
+The xhtml modules are part of the Jing distribution:
+ * [http://relaxng.org/ Relax NG Homepage]
+ * Thai Open Source: [http://www.thaiopensource.com/relaxng/ Relax NG], [http://www.thaiopensource.com/relaxng/xhtml/ xhtml modules]
+ * Jing and Trang at [http://code.google.com/p/jing-trang/ Google Code]
+ * xhtml modules in our local copy of the Jing distribution: [source:trunk/schema/thirdparty/jing-20091111/lib/xhtml/modules/basic-table.rng basic-table.rng],
+ [source:trunk/schema/thirdparty/jing-20091111/lib/xhtml/modules/list.rng list.rng],
+ [source:trunk/schema/thirdparty/jing-20091111/lib/xhtml/modules/attribs.rng attribs.rng],
+ [source:trunk/schema/thirdparty/jing-20091111/lib/xhtml/modules/datatypes.rng datatypes.rng]
+The original rng files can be converted into the Relax NG compact syntax using [http://www.thaiopensource.com/relaxng/trang-manual.html Trang]. Oxygen offers a GUI for this conversion.
+Diese Module übernehmen wir dann ohne weitere Änderungen. Alle Anpassungen werden in echo-import-xhtml gemacht.
+==== xhtml-basic-table
+We ignore Block.class in xhtml-basic-table: The following lines replace
+"Block.class |= table"  in xhtml-basic-table
+{{{
+echo.float.class  |= xhtml.table
+echo.anchor.types |= "table"
+}}}
+==== xhtml-list
+We ignore Block.class in xhtml-list: The following lines replace
+"List.class = ul | ol | dl",
+"Block.class |= List.class"
+{{{
+echo.float.class  |= xhtml.ul | xhtml.ol | xhtml.dl
+echo.anchor.types |= "ul" | "ol" | "dl"
+}}}
+Note that xhtml:ul, xhtml:ol, xhtml:dl do not correspond to <ul>, <ol>, <dl> in the DESpecs!
+==== xhtml-attribs
+We use the following xhtml elements: table, caption, tr, th, td;  dl, dt, dd; ol, ul, li.
+All these elements have Common.attrib (th and td via Cell.attrib).
+xml:lang and class are already in Common.attrib, and we add xml:id { xsd:NCName } to it
+(however, Common.attrib already includes the attribute id { xsd:ID })
+==== xhtml-datatypes ====
+==== xhtml-text ====
+Dieses Modul wird nicht importiert. Stattdessen werden Inline.model und Flow.model durch echo.flexible.content ersetzt:
+ * Inline.model = echo.flexible.content
+ * Flow.model   = echo.flexible.content
+ursprüngliche Definitionen:
+ * Inline.model = (text | Inline.class)*
+ * Block.mix = Block.class
+ * Block.model = Block.mix+
+ * Flow.model = (text | Inline.class | Block.class)*
+=== echo-import-mathml
+Note: Simple mathematical terms, i.e. numbers and variables, are marked using echo.num and echo.var (defined in echo-mathematics).
+mml.math.content erlaubt beliebige Elemente <mml:*> innerhalb von <mml:math>.
+This placeholder code above is good enough for the moment. We simply assume that the MathML parts are well-formed. This is plausible since the MathML code is created from a LaTeX formula by a MathML-converter.
+In addition, Oxygen seems to have a separate validation engine for MathML.