Fix bug in the compilation of nested case-of expressions

Fix a bug in the Elm compiler that caused defective code to be emitted in some cases where a case-of expression was contained in another case-of expression.
Also, add a regression test with a scenario that failed in the previous compiler implementation.

implement/pine/ElmTime/compile-elm-program/src/FirCompiler.elm

@@ -908,17 +908,31 @@ parseFunctionParameters expression =
 
 emitReferenceExpression : String -> EmitStack -> Result String Pine.Expression
 emitReferenceExpression name compilation =
-    case
-        emitApplyFunctionFromCurrentEnvironment
-            compilation
-            { functionName = name }
-            []
-    of
-        Just functionApplicationResult ->
-            functionApplicationResult
+    {-
+       Prioritize environmentDeconstructions before environmentFunctions here to
+       support shadowing for function parameters.
+       A source language like Elm does not support shadowing anyway, but the current
+       implementation of the Elm compiler sometimes lowers to Fir code that introduces declarations,
+       which can result in shadowing when nested.
+       An example is the `pseudoParamName` in `compileElmSyntaxCaseBlock`
+    -}
+    case Dict.get name compilation.environmentDeconstructions of
+        Just deconstruction ->
+            Ok
+                (pineExpressionForDeconstructions deconstruction
+                    (listItemFromIndexExpression_Pine 1 Pine.environmentExpr)
+                )
 
         Nothing ->
-            case Dict.get name compilation.environmentDeconstructions of
+            case
+                emitApplyFunctionFromCurrentEnvironment
+                    compilation
+                    { functionName = name }
+                    []
+            of
+                Just functionApplicationResult ->
+                    functionApplicationResult
+
                 Nothing ->
                     Err
                         (String.join ""
@@ -935,12 +949,6 @@ emitReferenceExpression name compilation =
                             ]
                         )
 
-                Just deconstruction ->
-                    Ok
-                        (pineExpressionForDeconstructions deconstruction
-                            (listItemFromIndexExpression_Pine 1 Pine.environmentExpr)
-                        )
-
 
 listTransitiveDependenciesOfExpression : EmitStack -> Expression -> Set.Set String
 listTransitiveDependenciesOfExpression dependenciesRelations expression =

implement/test-and-train/elm-interactive-scenarios-core/case-of/steps/151/expected-value.txt

@@ -0,0 +1 @@
+{ gamma = 79 }

implement/test-and-train/elm-interactive-scenarios-core/case-of/steps/151/submission.txt

@@ -0,0 +1,30 @@
+let
+    first_case_of list =
+        case list of
+        [] ->
+            Err "is empty"
+
+        _ ->
+            Ok { alfa = [ { beta = 79 } ] }
+
+    second_case_of list =
+        case list of
+        [] ->
+            Err "is empty"
+
+        first :: _ ->
+            Ok { gamma = first.beta }
+
+in
+case first_case_of [ 1, 3 ] of
+Err _ ->
+    "err in first"
+
+Ok firstRecord ->
+    case second_case_of firstRecord.alfa of
+    Err _ ->
+        "err in second"
+
+    Ok secondRecord ->
+        secondRecord
+