Update CheckComputationExpressions.fs

Author: edgarfgp

src/Compiler/Checking/Expressions/CheckComputationExpressions.fs

@@ -1435,12 +1435,29 @@ let rec TryTranslateComputationExpression
 
                     SynExpr.LetOrUse(false, false, true, true, [ condBinding ], whileExpr, mGuard, SynExprLetOrUseTrivia.Zero)
 
+                let firstBinding =
+                    SynBinding(
+                        accessibility = None,
+                        kind = SynBindingKind.Normal,
+                        isInline = false,
+                        isMutable = false,
+                        attributes = [],
+                        xmlDoc = PreXmlDoc.Empty,
+                        valData = SynInfo.emptySynValData,
+                        headPat = patFirst,
+                        returnInfo = None,
+                        expr = guardExpr,
+                        range = mGuard,
+                        debugPoint = DebugPointAtBinding.NoneAtSticky,
+                        trivia = SynBindingTrivia.Zero
+                    )
+
                 SynExpr.LetOrUse(
                     false,
                     false, // Pass through the isUse flag from binding info
                     true, // isFromSource is true for user-written code
                     true, // isComputed is true for bang let/let!
-                    [],
+                    [ firstBinding ],
                     body,
                     mGuard,
                     SynExprLetOrUseTrivia.Zero