Language Evolution, Metasyntactically

Abstract: Currently existing syntactic definitions employ many different notations (usually dialects of EBNF) with slight deviations among them, which prevent effi-cient automated processing. When changes in such notation are required either due to maintenance activities such as correction or evolution, or because a grammar col-lection is written in a different notation than the one required by the grammarware toolkit, we speak of metalanguage evolution: i.e., a special language evolution sce-nario when the language itself does not necessarily evolve, but the notation in which it is written, does. Notational changes need to be propagated to different levels, such as to parsers that used to work with the old notation, to grammars of those notations that served as explanation material, and to the existing grammarbase. The solution proposed in this paper, relies on composing a notation specification and expressing notation changes as transformations of that specification. These trans-formation steps are coupled to changes in the notation grammar (i.e., grammar for grammars) and to changes in other grammars written in the original notation. This paper explains the general setup of such an infrastructure, with links to the proto-typical implementation of the solution