Package orbital.logic.sign

Defines generic interfaces for formal languages.

See:
Description

Interface Summary

Expression	An interface for representations of expressions.
Expression.Composite	The base interface for all composite expressions that are composed of other expressions.
ExpressionBuilder	Defines a general interface for constructing complex expressions.
ExpressionSyntax	Defines general methods for constructing and handling expressions of a formal language.
Signature	A signature Σ is the set of names of all entities in a certain context.
Symbol	Represents a symbol of a signature.

Class Summary

SignatureBase	A basic signature implementation.
SymbolBase	Default representation of a syntactic symbol in a signature.

Exception Summary

ParseException

An exception thrown if an expression could not be parsed as desired.

Package orbital.logic.sign Description

Defines generic interfaces for formal languages.

A (free algebra) formal language is defined by all subclasses implementing the ExpressionSyntax interface. That interface handles expression construction and signature management, it provides builder methods for expressions and methods for expression parsing. The central data structure of this package is Expression which represents a term of a free algebra of terms over a signature, as abstract syntax.

The abstract syntax of a formal language only contains the logical content, and - contrary to the concrete syntax - ignores specific notation pecularities like commas, brackets for grouping, prefix, infix, etc.

See Also:

orbital.logic.sign.type, orbital.logic.sign.concrete, orbital.logic.imp, orbital.moon.logic.LogicParser