From d9c61bac70217841e9ec35d765fd9cba83079ce4 Mon Sep 17 00:00:00 2001
From: Sathya Gunasekaran <gsathya.ceg@gmail.com>
Date: Thu, 27 Oct 2022 16:43:31 +0100
Subject: [PATCH] [hir][be] Improve debug printing of invariant

---
 compiler/forget/src/HIR/InferReferenceEffects.ts | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/compiler/forget/src/HIR/InferReferenceEffects.ts b/compiler/forget/src/HIR/InferReferenceEffects.ts
index 96f293456a..34985dbaed 100644
--- a/compiler/forget/src/HIR/InferReferenceEffects.ts
+++ b/compiler/forget/src/HIR/InferReferenceEffects.ts
@@ -20,7 +20,7 @@ import {
   ValueKind,
 } from "./HIR";
 import { mapTerminalSuccessors } from "./HIRBuilder";
-import { printMixedHIR } from "./PrintHIR";
+import { printMixedHIR, printPlace } from "./PrintHIR";
 
 /**
  * For every usage of a value in the given function, infers the effect or action
@@ -196,7 +196,10 @@ class Environment {
       const kind = this.#values.get(value)!;
       mergedKind = mergedKind !== null ? mergeValues(mergedKind, kind) : kind;
     }
-    invariant(mergedKind !== null, "Expected at least value");
+    invariant(
+      mergedKind !== null,
+      `Expected at least one value at ${printPlace(place)}`
+    );
     return mergedKind;
   }