Evaluation and comparison of text-manipulation systems

A formal approach to the evaluation and comparison of text-manipulation systems is discussed. It is based on T-spaces, a class of transitive mathematical models, in terms of which the editable sets are exactly the recursively enumerable ones. Evaluation relies on the associated time/space complexity measures, some of which reflect the complexity of a system as a unity, while others are independent of the computational complexities of the text-manipulation operations. For all types of complexity measures linear speedup/compression theorems hold.<
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