The essence of the ITERATOR pattern
The Iterator pattern gives a clean interface for element-by-element access to a collection, independent of the collection's shape. Imperative iterations using the pattern have two simultaneous aspects: mapping and accumulating. Various existing functional models of iteration capture one or othe...
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| Format: | Conference item |
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2009
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| _version_ | 1826293876085751808 |
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| author | Gibbons, J Oliveira, B |
| author_facet | Gibbons, J Oliveira, B |
| author_sort | Gibbons, J |
| collection | OXFORD |
| description | The Iterator pattern gives a clean interface for element-by-element access to a collection, independent of the collection's shape. Imperative iterations using the pattern have two simultaneous aspects: mapping and accumulating. Various existing functional models of iteration capture one or other of these aspects, but not both simultaneously. We argue that C. McBride and R. Paterson's applicative functors (Applicative programming with effects, J. Funct. Program., 18 (1): 113, 2008), and in particular the corresponding traverse operator, do exactly this, and therefore capture the essence of the Iterator pattern. Moreover, they do so in a way that nicely supports modular programming. We present some axioms for traversal, discuss modularity concerns and illustrate with a simple example, the wordcount problem. © 2009 Copyright Cambridge University Press. |
| first_indexed | 2024-03-07T03:36:55Z |
| format | Conference item |
| id | oxford-uuid:bc9c36b2-e0ee-4dd2-b1fe-989aab7c3d1d |
| institution | University of Oxford |
| last_indexed | 2024-03-07T03:36:55Z |
| publishDate | 2009 |
| record_format | dspace |
| spelling | oxford-uuid:bc9c36b2-e0ee-4dd2-b1fe-989aab7c3d1d2022-03-27T05:25:34ZThe essence of the ITERATOR patternConference itemhttp://purl.org/coar/resource_type/c_5794uuid:bc9c36b2-e0ee-4dd2-b1fe-989aab7c3d1dSymplectic Elements at Oxford2009Gibbons, JOliveira, BThe Iterator pattern gives a clean interface for element-by-element access to a collection, independent of the collection's shape. Imperative iterations using the pattern have two simultaneous aspects: mapping and accumulating. Various existing functional models of iteration capture one or other of these aspects, but not both simultaneously. We argue that C. McBride and R. Paterson's applicative functors (Applicative programming with effects, J. Funct. Program., 18 (1): 113, 2008), and in particular the corresponding traverse operator, do exactly this, and therefore capture the essence of the Iterator pattern. Moreover, they do so in a way that nicely supports modular programming. We present some axioms for traversal, discuss modularity concerns and illustrate with a simple example, the wordcount problem. © 2009 Copyright Cambridge University Press. |
| spellingShingle | Gibbons, J Oliveira, B The essence of the ITERATOR pattern |
| title | The essence of the ITERATOR pattern |
| title_full | The essence of the ITERATOR pattern |
| title_fullStr | The essence of the ITERATOR pattern |
| title_full_unstemmed | The essence of the ITERATOR pattern |
| title_short | The essence of the ITERATOR pattern |
| title_sort | essence of the iterator pattern |
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