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diff --git a/src/data/composite/data/withFilteredList.js b/src/data/composite/data/withFilteredList.js
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+// Applies a filter - an array of truthy and falsy values - to the index-
+// corresponding items in a list. Items which correspond to a truthy value
+// are kept, and the rest are excluded from the output list.
+//
+// TODO: It would be neat to apply an availability check here, e.g. to allow
+// not providing a filter at all and performing the check on the contents of
+// the list (though on the filter, if present, is fine too). But that's best
+// done by some shmancy-fancy mapping support in composite.js, so a bit out
+// of reach for now (apart from proving uses built on top of a more boring
+// implementation).
+//
+// TODO: There should be two outputs - one for the items included according to
+// the filter, and one for the items excluded.
+//
+// See also:
+//  - withMappedList
+//  - withSortedList
+//
+// More list utilities:
+//  - excludeFromList
+//  - fillMissingListItems
+//  - withFlattenedList, withUnflattenedList
+//  - withPropertyFromList, withPropertiesFromList
+//
+
+import {input, templateCompositeFrom} from '#composite';
+
+export default templateCompositeFrom({
+  annotation: `withFilteredList`,
+
+  inputs: {
+    list: input({type: 'array'}),
+    filter: input({type: 'array'}),
+  },
+
+  outputs: ['#filteredList'],
+
+  steps: () => [
+    {
+      dependencies: [input('list'), input('filter')],
+      compute: (continuation, {
+        [input('list')]: list,
+        [input('filter')]: filter,
+      }) => continuation({
+        '#filteredList':
+          list.filter((item, index) => filter[index]),
+      }),
+    },
+  ],
+});