Implement parent()

src/_parent.luau

@@ -0,0 +1,26 @@
+if not game then script = require "test/relative-string" end
+
+local graph = require(script.Parent.graph)
+type Node<T> = graph.Node<T>
+
+export type Source<T> = (() -> T) & ((value: T) -> T)
+
+local function parent<T>(fn: () -> T): T
+    local node = graph.get_scope()
+    if not node then error("") end
+
+    local parent_node = node.owner
+    if not parent_node then error("") end
+
+    graph.push_scope(parent_node :: Node<unknown>)
+
+    local ok, result = pcall(fn)
+
+    graph.pop_scope()
+
+    if not ok then error(result, 0) end
+
+    return result
+end
+
+return parent

src/context.luau

@@ -9,7 +9,7 @@ local push_scope = graph.push_scope
 local pop_scope = graph.pop_scope
 local set_context = graph.set_context
 
-export type Context<T> = (() -> T) & (<U>(T, () -> U) -> U)
+export type Context<T> = (() -> T) & (<U>(T, () -> U) -> U)  & ((T, () -> ()) -> ())
 
 local nil_symbol = newproxy()
 local count = 0

src/init.luau

@@ -15,6 +15,7 @@ local effect = require(script.effect)
 local derive = require(script.derive)
 local cleanup = require(script.cleanup)
 local untrack = require(script.untrack)
+local parent = require(script._parent)
 local read = require(script.read)
 local batch = require(script.batch)
 local context = require(script.context)
@@ -68,6 +69,7 @@ local vide = {
     -- util
     cleanup = cleanup,
     untrack = untrack,
+    parent = parent,
     read = read,
     batch = batch,
     context = context,