Exploiting XPG for Visual Languages Definition, Analysis and Development

AbstractIn this paper we present the approach based on the formalism of Extended Positional Grammars (XPG) for specifying, designing and implementing visual languages. Special emphasis is put on describing the benefits deriving from the use of such formalism. Indeed, it allows us to exploit the well-established theoretical background and techniques developed for string languages in the setting of visual languages. As a matter of fact, an efficient syntactic analysis of visual languages can be effectively perfomed by using a suitable extension of LR techniques. Moreover, syntax-direct translations can be used to verify properties of visual sentences during a semantic analysis phase. Finally, a visual environment for a target visual language can be automatically generated by exploiting a YACC-like tool based on XPG