Hi,
I have the following schema definition :
The requirement is to not allow  leading and trailing spaces.

<xsd:simpleType name="Comment_T">
<xsd:annotation>
<xsd:documentation>
Comment text
</xsd:documentation>
</xsd:annotation>
<xsd:restriction base="xsd:string">
<xsd:maxLength value="2000"/>
<xsd:pattern value="(\S(?:.*\S)?)"/>
</xsd:restriction>
</xsd:simpleType>

Now I need to change it so that following expression are also not
allowed : NONE, N/A, =, !=, <, >, <=, and >=
Note that The symbols shouldn't be contained in any part of the data
provided as part of Comment_T.
Thus a string like SNONE or sN/Ass or s<dd are also invalid values.

I am not able to make out the appropriate regular experession which
would meet this requirement.
I will appreciate any suggestions regarding this.

Thanks,
Satish Kataria