The Typing System to Provide Compositional Thinking About Data Flows

The paper considers the approach to solving the problem of preventing the information system vulnerability that arises due to the insertion and / or performance of a semantically incorrect script (XSS-vulnerability). The solution of this task suggests modelling the information exchange between active objects. Modelling is supposed to be carried out within the framework of the basic applicative computing system, in which the code fragments can be modelled by applicative objects. An important part of the task is to check the correctness of the scenarios composition, which requires the tools make compositional thinking about data flows, both when they are processed by scripts and contain them. The correctness is proposed to be provided by supporting the fairly strong typing system that excludes incorrect combinations of scenarios. The type system is assumed to be immersed into the applicative environment. The system is proposed to be built on the basis of the homotopy type theory, which ensures, in particular, the introduction of independent and dependent types, as well as the definition of recursion and induction principles for them. Partial approbation of typing constructions is performed with the example of the problem of semantic support for the implementation of the best available technologies (BAT).