Lazy UTP
نویسنده
چکیده
We integrate non-strict computations into the Unifying Theories of Programming. After showing that this is not possible with designs, we develop a new relational model representing undefinedness independently of non-termination. The relations satisfy additional healthiness conditions that model dependence in computations in an elegant algebraic form using partial orders. Programs can be executed according to the principle of lazy evaluation, otherwise known from functional programming languages. We extend the theory to support infinite data structures and give examples to show their use in programs.
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