contextual void construction

examples/programs/match/main.bro

@@ -58,6 +58,10 @@ payload_of :: func(d Data) i32 {
 	return v
 }
 
+make_box :: func() Box {
+	return Box{ point = Point{ x = 4, y = 0 } }
+}
+
 main :: func() i32 {
 	acc i32 = 0
 
@@ -93,8 +97,8 @@ main :: func() i32 {
 	}
 	acc = acc + bucket # +5
 
-	# void-payload variant: bare-key construction + a no-capture arm
-	e Box = Box{ empty }
+	# void-payload variant: contextual construction (`.empty` coerces to Box) + no-capture arm
+	e Box = .empty
 	hit i32 = 0
 	match e {
 		.point |pt|: hit = pt.x
@@ -110,6 +114,12 @@ main :: func() i32 {
 	}
 	acc = acc + b.point.x # +10 (mutated through the @mut Point)
 
-	# 50 + 47 + 3 + 2 + 5 + 7 + 10 = 124
-	return acc - 124
+	# match directly on a call result (no need to bind it to a variable first)
+	match make_box() {
+		.point |p|: acc = acc + p.x # +4
+		.empty:     hit = hit
+	}
+
+	# 50 + 47 + 3 + 2 + 5 + 7 + 10 + 4 = 128
+	return acc - 128
 }