A data representation is read and parsed. A declaration referencing an executable namespace is recognized. An expression is recognized. A name (declared within the executable namespace) within the expression having zero or more additional data representations is also recognized. In response, functions corresponding to the name and additional data representations are recursively resolved, and caused to be invoked and executed, with the execution results of the inner functions successively provided for use in the execution of the outer functions. For each function, the function or a creator to create the function is instantiated. The instantiating is effectuated by following a path enumerated in the declaration for locating functions of the namespace. If a creator of the function is located and instantiated, the function is created using the function creator, and then the created function is instantiated. Upon instantiation, the referenced function is invoked and executed.