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By contrast, MOF Attributes are denoted as minor concepts, and as such are represented differently. In their case, the attribute
name is followed by a colon or equal sign, followed in turn by the value of the attribute. The attributes’ representations
may be separated only by white space, or with a semi-colon terminator. White-space-only separation is possible because it
is always feasible to know how many white-space separated ‘words’ will appear in an attribute’s value. No simple attributes
are permitted white space within their values except string-typed attributes, whose values are delimited by a number of possible
delimiting characters, or left undelimited, if their contents make this possible. Attributes whose values are class instances
are represented either as instance references or as full instance declarations, depending on the nature of the attribute.
These representations do have more than one ‘word’ in their value, but do not cause problems because the number of words is
always fixed and known to the parser.
References are displayed with the reference name followed by a colon or equal sign and the representation of the class instance
that is referred to. This is almost identical to the representation of attributes, which could be seen as violating the principle
of ‘different forms for different features.’ However, the role of references in the MOF is in many ways to provide a class
instance with attribute-like access to other class-instances that are related by association links. For this reason, the underlying
‘feature’ of references and class-instance valued attributes is essentially the same, and thus their representations should
in fact be similar.