From bfdd295ac5462fbacbf72cb50dbed8384dab225a Mon Sep 17 00:00:00 2001
From: John Lancaster <32917998+jsl12@users.noreply.github.com>
Date: Sat, 21 Feb 2026 00:01:35 -0600
Subject: [PATCH] iadd

---
 src/daglib/set.py | 24 +++++++++++++++++-------
 1 file changed, 17 insertions(+), 7 deletions(-)

diff --git a/src/daglib/set.py b/src/daglib/set.py
index fce1cbd..954c931 100644
--- a/src/daglib/set.py
+++ b/src/daglib/set.py
@@ -56,16 +56,26 @@ class DAGSet(MutableSet[T]):
 
     # --- in-place operator support ---
 
-    # def __ior__(self, other: Iterable[T]) -> DAGSet[T]:
-    #     # a |= b  => add everything in other
-    #     return self
-
-    # def __iadd__(self, other: Iterable[T]) -> DAGSet[T]:
-    #     # a += b => update/extend
-    #     return self
+    def __iadd__(self, other: Iterable[T]) -> DAGSet[T]:
+        # a += b => update/extend
+        match other:
+            case set():
+                self |= other
+            case str():
+                self |= {other}
+            case Iterable():
+                self |= set(other)
+            case _:
+                self |= {other}
+        return self
 
     # def __isub__(self, other: Iterable[T]) -> DAGSet[T]:
     #     # a -= b => remove those in other
+    #     match other:
+    #         case set():
+    #             self -= other
+    #         case _:
+    #             self -= set(other)
     #     return self
 
     # def __iand__(self, other: Iterable[T]) -> DAGSet[T]: