Using loops in XSD?

[=?ISO-8859-1?Q?Christian_R=FChl?=]

hi @all!

i have a little problem with xsd. is it possible to define a loop in a
schema?

the xml files i want to validate look like this:

- product
-- component
--- sub-component
--- sub-component
---- sub-component
-- component
--- sub-component
---- sub-component

each (sub-)component can have one or more own sub-components and so
on... there is a static solution needed because the xml file is
usually written by hand. writing it by using to many references makes
it more likely to make a mistake and more difficult to locate an
error.

i really hope you can help me with that. i didn't find a real hint
yet. :(

Mfg,
Christian Rühl

[usenet]

On 19 Nov, 14:41, "Christian Rühl" <[e-mail]:

On 19 Nov., 14:57, Pavel Lepin <[e-mail]:

Christian Rühl <[e-mail] in
<[e-mail]>:

the xml files i want to validate look like this:
-- component
--- sub-component
--- sub-component
---- sub-component
-- component
--- sub-component
---- sub-component

<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema">
<xs:element name="sub">
<xs:complexType>
<xs:choice minOccurs="0" maxOccurs="unbounded">
<xs:element ref="sub"/>
</xs:choice>
</xs:complexType>
</xs:element>
</xs:schema>

Another option might be:

<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema">
<xs:element name="sub">
<xs:complexType>
<xs:sequence>
<!-- You might want some extra stuff here. -->
<xs:element ref="sub" minOccurs="0" maxOccurs="unbounded"/>
</xs:sequence>
</xs:complexType>
</xs:element>
</xs:schema>

Or (tweak of Pavel's):

<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema">
<xs:element name="sub">
<xs:complexType>
<xs:choice>
<xs:element ref="subdetails" type="subdetails"/>
<xs:element ref="sub" minOccurs="0" maxOccurs="unbounded"/>
</xs:choice>
</xs:complexType>
</xs:element>
</xs:schema>

The difference between the two depends on whether a sub-component with
sub-components _only_ have sub-components, or has other data plus sub-
components. (Wow - that's a lot of sub-components!)

HTH,

Pete Cordell
Codalogic
Visit http://www.codalogic.com/lmx/
for XML Schema to C++ data binding