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Version: 6.x


The constant operator is used to create properties without parameters which always return the same value. This value can be static objects of custom and built-in classes as well as the special NULL value.


Static objects of custom classes are specified as <class name>.<object name>.

Static objects of built-in classes are specified by special literals.


CLASS Direction {
north, east, south, west // declaring static objects

// A constant property is created from a Direction.north object which is then used
// by the comparison operator to construct the isNorth property
isNorth (Direction d) = d == Direction.north;

// A constant property is created from a literal describing the date
defaultDate() = 1982_07_13;

age 'Age' = DATA INTEGER (Man);
// A constant property is created from an integer (integer literal)
isChild (Man m) = age(m) < 17;