From 8bf4f27f304a55faeef8f94600af38a70111c78f Mon Sep 17 00:00:00 2001
From: Mark Spanbroek <mark@spanbroek.net>
Date: Tue, 4 May 2021 16:17:09 +0200
Subject: [PATCH] Avoid wrapping option in option when using .?[] operator

---
 questionable/options.nim     | 9 +++++++++
 testmodules/options/test.nim | 5 +++++
 2 files changed, 14 insertions(+)

diff --git a/questionable/options.nim b/questionable/options.nim
index b576627..748dd84 100644
--- a/questionable/options.nim
+++ b/questionable/options.nim
@@ -62,6 +62,15 @@ template `|?`*[T](option: ?T, fallback: T): T =
   else:
     fallback
 
+macro `.?`*[T](option: ?T, brackets: untyped{nkBracket}): untyped =
+  let index = brackets[0]
+  quote do:
+    type U = typeof(`option`.unsafeGet().?[`index`].unsafeGet())
+    if `option`.isSome:
+      `option`.unsafeGet().?[`index`]
+    else:
+      U.none
+
 Option.liftUnary(`-`)
 Option.liftUnary(`+`)
 Option.liftUnary(`@`)
diff --git a/testmodules/options/test.nim b/testmodules/options/test.nim
index 260fff3..c069e3d 100644
--- a/testmodules/options/test.nim
+++ b/testmodules/options/test.nim
@@ -230,6 +230,11 @@ suite "optionals":
 
     check (a & b) == 42.some
 
+  test ".?[] avoids wrapping option in option":
+    let a = @[41, 42].some
+
+    check a.?[1] == 42.some
+
   test "examples from readme work":
 
     var x: ?int