Example 10     <<      >>       intro       contents     

An attribute of CDATA type can contain any character if it conforms to well formedness constraints. NMTOKEN type can contain only letters, digits and point [ . ] , hyphen [ - ], underline [ _ ] and colon [ : ] . NMTOKENS can contain the same characters as NMTOKEN plus whitespaces. White space consists of one or more space characters, carriage returns, line feeds, or tabs.

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The attributes bbb and ccc must be always present, the attribute aaa is optional:

               <!ELEMENT attributes (#PCDATA)>
               <!ATTLIST attributes 
                         aaa CDATA #IMPLIED
                         bbb NMTOKEN #REQUIRED
                         ccc NMTOKENS #REQUIRED>
               
            


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All required attributes are present and their values are of the correct type:

               <!DOCTYPE tutorial SYSTEM "tutorial.dtd">

               <attributes aaa="#d1" bbb="a1:12" ccc=" 3.4 div      -4"/>
               
            

All required attributes are present and their values are of the correct type:

               <!DOCTYPE tutorial SYSTEM "tutorial.dtd">

               <attributes bbb="a1:12" 
               ccc="3.4
               div 
               -4"/>
               
            

  Documents with errors   HOME     

The character # is not permitted in attributes of type NMTOKEN and NMTOKENS:

               <!DOCTYPE tutorial SYSTEM "tutorial.dtd">

               <attributes aaa="#d1" bbb="#d1" ccc="#d1"/>
               
            

The space character is forbiden in attributes of NMTOKEN type:

               <!DOCTYPE tutorial SYSTEM "tutorial.dtd">

               <attributes bbb="A B C" ccc="A      B      C"/>