Fast and loose reasoning is morally correct
Functional programmers often reason about programs as if they were written in a total language, expecting the results to carry over to non-total (partial) languages. We justify such reasoning. Two languages are defined, one total and one partial, with identical syntax. The semantics of the partial l...
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2006
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_version_ | 1797086377218670592 |
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author | Danielsson, N Hughes, J Gibbons, J Jansson, P |
author_facet | Danielsson, N Hughes, J Gibbons, J Jansson, P |
author_sort | Danielsson, N |
collection | OXFORD |
description | Functional programmers often reason about programs as if they were written in a total language, expecting the results to carry over to non-total (partial) languages. We justify such reasoning. Two languages are defined, one total and one partial, with identical syntax. The semantics of the partial language includes partial and infinite values, and all types are lifted, including the function spaces. A partial equivalence relation (PER) is then defined, the domain of which is the total subset of the partial language. For types not containing function spaces the PER relates equal values, and functions are related if they map related values to related values. It is proved that if two closed terms have the same semantics in the total language, then they have related semantics in the partial language. It is also shown that the PER gives rise to a bicartesian closed category which can be used to reason about values in the domain of the relation. Copyright © 2006 ACM. |
first_indexed | 2024-03-07T02:21:10Z |
format | Conference item |
id | oxford-uuid:a3f59020-133a-4496-b0c1-7832d532e496 |
institution | University of Oxford |
last_indexed | 2024-03-07T02:21:10Z |
publishDate | 2006 |
record_format | dspace |
spelling | oxford-uuid:a3f59020-133a-4496-b0c1-7832d532e4962022-03-27T02:30:40ZFast and loose reasoning is morally correctConference itemhttp://purl.org/coar/resource_type/c_5794uuid:a3f59020-133a-4496-b0c1-7832d532e496Symplectic Elements at Oxford2006Danielsson, NHughes, JGibbons, JJansson, PFunctional programmers often reason about programs as if they were written in a total language, expecting the results to carry over to non-total (partial) languages. We justify such reasoning. Two languages are defined, one total and one partial, with identical syntax. The semantics of the partial language includes partial and infinite values, and all types are lifted, including the function spaces. A partial equivalence relation (PER) is then defined, the domain of which is the total subset of the partial language. For types not containing function spaces the PER relates equal values, and functions are related if they map related values to related values. It is proved that if two closed terms have the same semantics in the total language, then they have related semantics in the partial language. It is also shown that the PER gives rise to a bicartesian closed category which can be used to reason about values in the domain of the relation. Copyright © 2006 ACM. |
spellingShingle | Danielsson, N Hughes, J Gibbons, J Jansson, P Fast and loose reasoning is morally correct |
title | Fast and loose reasoning is morally correct |
title_full | Fast and loose reasoning is morally correct |
title_fullStr | Fast and loose reasoning is morally correct |
title_full_unstemmed | Fast and loose reasoning is morally correct |
title_short | Fast and loose reasoning is morally correct |
title_sort | fast and loose reasoning is morally correct |
work_keys_str_mv | AT danielssonn fastandloosereasoningismorallycorrect AT hughesj fastandloosereasoningismorallycorrect AT gibbonsj fastandloosereasoningismorallycorrect AT janssonp fastandloosereasoningismorallycorrect |