Here is an e-mail discussing concerning this :
>Tom,
>>
>> Here is my understanding of the specs concerning the
>> sld:ParameterValueType" (which is taken form the sld 1.0 doc
>> section 11.1.3)
>>
>>
>> <xs:element name="CssParameter"
>> type="sld:ParameterValueType"/> <xs:complexType
>> name="ParameterValueType" mixed="true"> <xs:choice
>> minOccurs="0" maxOccurs="unbounded"> <xs:element
>> ref="ogc:expression"/> </xs:choice> </xs:complexType>
>>
>> The parameter values are allowed to be complex expressions
>> for maximum
>> flexibility.
>> The 'mixed="true"' definition means that regular text may be mixed in
>> with various sub-expressions, implying a text-substitution model for
>> parameter values. Numeric and character-string data types are not
>> distinguished, which may cause some complications.
>>
>> Here are some usage examples:
>>
>> <CssParameter name="stroke-width">3</CssParameter>
>>
>> <CssParameter name="stroke-width">
>> <ogc:Literal>3</ogc:Literal>
>> </CssParameter>
>>
>> <CssParameter name="stroke-width">
>> <ogc:Add>
>> <ogc:PropertyName>A</ogc:PropertyName>
>> <ogc:Literal>2</ogc:Literal>
>> </ogc:Add>
>> </CssParameter>
>>
>> <Label>This is city "<ogc:PropertyName>NAME</ogc:PropertyName>"
>> of state <ogc:PropertyName>STATE</ogc:PropertyName></Label>
>>
>>
>> I think supporting <Label>label_value</Label> should be valid. I
>> downladed your sld file and fter adding the schemas at the
>> top, It did
>> valiadte using xml-spy. Does It make sense ?
>> (Note that I initially was supporting the label inside a
>> propertyName
>> and the code is still there but commented out).
>>
I retried this with just:
<Label>OBSDATE</Label>
..and it validated.
So both constructs are valid; should we support both when ingesting SLD
XML, and output one style when producing?
