On the Composition of Non-parahalting Macro Instructions
نویسنده
چکیده
An attempt to use the Times macro, [2], was the origin of writing this article. First, the semantics of the macro composition as developed in [23, 3, 4] is extended to the case of macro instructions which are not always halting. Next, several functors extending the memory handling for SCMFSA, [18], are defined; they are convenient when writing more complicated programs. After this preparatory work, we define a macro instruction computing the Fibonacci sequence (see the SCM program computing the same sequence in [10]) and prove its correctness. The semantics of the Times macro is given in [2] only for the case when the iterated instruction is parahalting; this is remedied in [17].
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