data: thingList

2 files changed, 45 insertions, 0 deletions

diff --git a/src/data/composite/wiki-properties/index.js b/src/data/composite/wiki-properties/index.js
index 5328d17e..e35948e7 100644
--- a/src/data/composite/wiki-properties/index.js
+++ b/src/data/composite/wiki-properties/index.js
@@ -25,5 +25,6 @@ export {default as simpleDate} from './simpleDate.js';
 export {default as simpleString} from './simpleString.js';
 export {default as singleReference} from './singleReference.js';
 export {default as thing} from './thing.js';
+export {default as thingList} from './thingList.js';
 export {default as urls} from './urls.js';
 export {default as wikiData} from './wikiData.js';
diff --git a/src/data/composite/wiki-properties/thingList.js b/src/data/composite/wiki-properties/thingList.js
new file mode 100644
index 00000000..f4c00e06
--- /dev/null
+++ b/src/data/composite/wiki-properties/thingList.js
@@ -0,0 +1,44 @@
+// A list of Things, provided directly rather than by reference.
+//
+// Essentially the same as wikiData, but exposes the list of things,
+// instead of keeping it private.
+
+import {input, templateCompositeFrom} from '#composite';
+import {isThingClass, validateWikiData} from '#validators';
+
+import {exposeConstant, exposeUpdateValueOrContinue}
+  from '#composite/control-flow';
+
+export default templateCompositeFrom({
+  annotation: `wikiData`,
+
+  compose: false,
+
+  inputs: {
+    class: input.staticValue({
+      validate: isThingClass,
+      defaultValue: null,
+    }),
+  },
+
+  update: ({
+    [input.staticValue('class')]: thingClass,
+  }) => ({
+    validate:
+      validateWikiData({
+        referenceType:
+          (thingClass
+            ? thingClass[Symbol.for('Thing.referenceType')]
+            : ''),
+      }),
+  }),
+
+  steps: () => [
+    exposeUpdateValueOrContinue(),
+
+    exposeConstant({
+      value: input.value([]),
+    }),
+  ],
+});
+