# Wiki Discussion: Difference List

**URL:** <https://swi-prolog.discourse.group/t/wiki-discussion-difference-list/960>\
**Category:** Wiki Discussion\
**Created:** [July 16, 2019, 9:41am UTC](https://swi-prolog.discourse.group/t/wiki-discussion-difference-list/960 "2019-07-16T09:41:26Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![Wiki](https://avatars.discourse-cdn.com/v4/letter/w/e8c25b/32.png) [@Wiki](https://swi-prolog.discourse.group/u/Wiki)\
**Post date:** [July 16, 2019, 9:41am UTC](https://swi-prolog.discourse.group/t/wiki-discussion-difference-list/960/1 "2019-07-16T09:41:26Z")

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This is a topic to discuss the Wiki

[Wiki: Difference List](https://swi-prolog.discourse.group/t/wiki-difference-list/959)

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**Author:** ![EricGT](https://avatars.discourse-cdn.com/v4/letter/e/f1d935/32.png) [@EricGT](https://swi-prolog.discourse.group/u/EricGT)\
**Post date:** [July 20, 2020, 12:36pm UTC](https://swi-prolog.discourse.group/t/wiki-discussion-difference-list/960/2 "2020-07-20T12:36:17Z")

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When looking at solving problems with difference list and accumulator passing a few other things to consider

1. [edcg](https://www.swi-prolog.org/pack/list?p=edcg)
2. [with\_state](https://www.swi-prolog.org/pack/file_details/with_state/prolog/with_state.pl)

> **Personal notes**
>
> For an example of a predicate that can use both proper and partial list in the same predicate see permutation/2. ([source](https://github.com/SWI-Prolog/swipl-devel/blob/e36d3fd7c56615b83e5c7ae9ba249fbd850f27d1/library/lists.pl#L419-L472))