ml2-grammar.txt

/********* ML2 Simplified Grammar ************/

This file contains the simplified version of ML2's grammar.
The syntax of this file is not formal but intends to resemble BNF like rules.
The list of symbols and their semantics is the following:
	Pipe				Option selection rules
	Asterisk			Repetition rule
	Question Mark		Optional rule
	Capital Letters		Terminal (omitted) rule

/********************************************/


Entity := Class | Individual ;
Class := (FirstOrderClass | HighOrderClass | OrderlessClass | DataType) ({ (Feature | FeatureAssignment)* })?

FirstOrderClass := class NAME MLTRelations*
HighOrderClass := order NUMBER class NAME MLTRelations* ;
OrderlessClass := orderless class NAME MLTRelations* ;
Individual := individual NAME Instantiation ({ (Feature | FeatureAssignment)* })?
DataType := datatype NAME MLTRelations* ({ (Feature | FeatureAssignment)* })? ;

MLTRelations := Instantiation | Specialization | Subordination | Categorization | Powertyping

Instantiation := : Class (, Class)*
Specialization := specializes Class (, Class)*
Subordination := subordinatedTo Class (, Class)*
Categorization := CategorizationType Class
Powertyping := isPowertypeOf Class

CategorizationType := categorizes | completeCategorizes | disjointCategorizes | partitions

Feature := Reference | Attribute | RegularityReference | RegularityAttribute
Reference := ref NAME : Multiplicity? Class Subsets? IsOpposite?
Multiplicity := [ CARDINALITY .. CARDINALITY ]
Subsets := subsets Feature (, Feature)*
IsOpposite := isOppositeTo Feature
Attribute := att NAME : Multiplicity? Datatype Subsets?

FeatureAssignment := ReferenceAssignment | AttributeAssignment
ReferenceAssignment := ref Feature = Entity | { Entity (, Entity)* }
AttributeAssignment := att Feature = Value | { Value (,Value)* }
Value := STRING | NUMBER | BOOLEAN | Entity

RegularityReference := regularity Reference RegularityType? Feature
RegularityAttribute := regularity Attribute RegularityType? Feature
RegularityType := determinesValue | determinesMinValue | determinesMaxValue | determinesAllowedValues | determinesType | determinesAllowedTypes