I have an atribute named item_category and I want to use as enumerated values ( h/w | s/w). Is that possible? And If it is how? Basically i tried:
<!ATTLIST item
item_category (h/w | s/w) #REQUIRED>
but I get errors like Expecting "|". and Missing attribute presence #IMPLIED, #Required... and Expecting ")". so it actually doesnt take forward slash as a value.
I don't think that you can directly.
The values for an enumeration in an ATTLIST have to be either NOTATION or NMTOKEN.
https://www.w3.org/TR/REC-xml/#NT-AttlistDecl
[Definition: Enumerated attributes have a list of allowed values in their declaration ]. They must take one of those values. There are two kinds of enumerated attribute types:
Enumerated Attribute Types [57] EnumeratedType ::= NotationType | Enumeration
[58] NotationType ::= 'NOTATION' S '(' S? Name (S? '|' S? Name)* S? ')' [VC: Notation Attributes] [VC: One Notation Per Element Type] [VC: No Notation on Empty Element] [VC: No Duplicate Tokens]
[59] Enumeration ::= '(' S? Nmtoken (S? '|' S? Nmtoken)* S? ')' [VC: Enumeration] [VC: No Duplicate Tokens]
A / isn't allowed in the value of an NMTOKEN.
It is allowed as the value of a NOTATION.
<!NOTATION hw PUBLIC "h/w">
<!NOTATION sw PUBLIC "s/w">
<!ATTLIST item
item_category NOTATION (hw|sw) #REQUIRED>
]>