1 files changed, 33 insertions, 0 deletions
diff --git a/importer.moon b/importer.moon
new file mode 100644
index 0000000..48a3800
--- /dev/null
+++ b/importer.moon
@@ -0,0 +1,33 @@
+-- This file defines Importer, which is a type of table that can import from other tables
+
+import_to_1_from = (host, to_import)->
+    if host_mt = getmetatable(host)
+        if host_mt.__import
+            host_mt.__import(host, to_import)
+            return
+    for k,v in pairs(to_import)
+        host[k] = v
+_imports = setmetatable({}, {__mode:"k"})
+Importer = setmetatable({
+    __index: (key)=> _imports[@][key]
+    __import: (to_import)=>
+        imports = assert _imports[@]
+        for k,v in pairs(to_import)
+            imports[k] = v
+            continue if v == to_import
+            conflict = @[k]
+            import_to_1_from(conflict, v) if type(conflict) == 'table'
+}, {
+    __call: (t)=>
+        _imports[t] = {}
+        setmetatable(t, @)
+        return t
+})
+
+_1_forked = =>
+    f = Importer{}
+    _imports[f] = assert _imports[@]
+    import_to_1_from(f, @)
+    return f
+
+return {:Importer, :import_to_1_from, :_1_forked}