The majority of existing modelling languages are tightly coupled with an associated data structure. This complicates their use as modelling languages for a model composed of an external data structure.
To overcome these difficulties, the programming language XL uses an abstract data model as an interface between its graph query and rewriting facilities and the graph data structure of the model. By implementing this graph model interface for your own data structure, XL is able to operate on your structure and, hence, can immediately be used as modelling language.
Currently, this website provides two applications of XL’s graph model interface: