lout

1 files changed, 22 insertions, 0 deletions

diff --git a/tools/parse-layout.js b/tools/parse-layout.js
index f2443fd..b389669 100644
--- a/tools/parse-layout.js
+++ b/tools/parse-layout.js
@@ -430,6 +430,28 @@ remap_to_range(sets.map)
 remap_to_range(sets.suit)
 remap_to_range(sets.country)
 
+function object_group_by(items, callback) {
+	let groups = {}
+	if (typeof callback === "function") {
+		for (let item of items) {
+			let key = callback(item)
+			if (key in groups)
+				groups[key].push(item)
+			else
+				groups[key] = [ item ]
+		}
+	} else {
+		for (let item of items) {
+			let key = item[callback]
+			if (key in groups)
+				groups[key].push(item)
+			else
+				groups[key] = [ item ]
+		}
+	}
+	return groups
+}
+
 delete sets.type.city
 
 sets.cities = arrays