Confluence Properties of Extensional and Non-Extensional λ-Calculi with Explicit Substitutions
نویسنده
چکیده
This paper studies confluence properties of extensional and non-extensional λ-calculi with explicit substitutions, where extensionality is interpreted by η-expansion. For that, we propose a general scheme for explicit substitutions which describes those abstract properties that are sufficient to guarantee confluence. Our general scheme makes it possible to treat at the same time many well-known calculi such as λσ, λσ⇑ and λυ, or some other new calculi that we propose in this paper. We also show for those calculi not fitting in the general scheme that can be translated to another one fitting the scheme, such as λs, how to reason about confluence properties of their extensional and non-extensional versions.
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