fixup regex again

src/Algorithm.ts

@@ -87,7 +87,7 @@ export default class Algorithm extends Builder {
                 continue;
               }
               const completionyThing = part.contents.match(
-                /\b(ReturnIfAbrupt|(^|(?<=, ))[tT]hrow a|[rR]eturn (Normal|Throw|Return)?Completion\(|[rR]eturn( a| a new| the)? Completion Record|the result of evaluating)(\b|$)|(?<=[\s(])\?\s/
+                /\b(ReturnIfAbrupt\b|(^|(?<=, ))[tT]hrow (a\b|the\b|$)|[rR]eturn (Normal|Throw|Return)?Completion\(|[rR]eturn( a| a new| the)? Completion Record\b|the result of evaluating\b)|(?<=[\s(])\?\s/
               );
               if (completionyThing != null) {
                 if (returnType?.kind === 'completion') {

test/typecheck.js

@@ -287,6 +287,28 @@ describe('typechecking completions', () => {
         }
       );
 
+      await assertLint(
+        positioned`
+        <emu-clause id="example" type="abstract operation">
+        <h1>
+          ExampleAlg (): a Number
+        </h1>
+        <dl class="header">
+        </dl>
+        <emu-alg>
+          1. Let _foo_ be a thing.
+          1. ${M}Throw _foo_.
+        </emu-alg>
+        </emu-clause>
+        `,
+        {
+          ruleId: 'completiony-thing-in-non-completion-algorithm',
+          nodeType: 'emu-alg',
+          message:
+            'this would return a Completion Record, but the containing AO is declared not to return a Completion Record',
+        }
+      );
+
       await assertLint(
         positioned`
         <emu-clause id="example" type="abstract operation">