implements PR-12.1

prometeu-compiler/frontends/prometeu-frontend-pbs/src/main/java/p/studio/compiler/pbs/semantics/PbsFlowExpressionAnalyzer.java

@@ -32,7 +32,6 @@ final class PbsFlowExpressionAnalyzer {
     }
 
     private final PbsFlowTypeOps typeOps;
-    private BlockAnalyzer blockAnalyzer;
 
     PbsFlowExpressionAnalyzer(final PbsFlowTypeOps typeOps) {
         this.typeOps = typeOps;
@@ -50,35 +49,33 @@ final class PbsFlowExpressionAnalyzer {
             final ExprUse use,
             final boolean valueContext,
             final BlockAnalyzer blockAnalyzer) {
-        final var previousBlockAnalyzer = this.blockAnalyzer;
+        return analyzeExpressionInternal(
-        this.blockAnalyzer = blockAnalyzer;
+                expression,
-        try {
+                new PbsFlowExpressionContext(
-            return analyzeExpressionInternal(
+                        scope,
-                    expression,
+                        expectedType,
-                    scope,
+                        returnType,
-                    expectedType,
+                        resultErrorName,
-                    returnType,
+                        receiverType,
-                    resultErrorName,
+                        model,
-                    receiverType,
+                        diagnostics,
-                    model,
+                        use,
-                    diagnostics,
+                        valueContext,
-                    use,
+                        blockAnalyzer));
-                    valueContext);
-        } finally {
-            this.blockAnalyzer = previousBlockAnalyzer;
-        }
     }
+
     private ExprResult analyzeExpressionInternal(
             final PbsAst.Expression expression,
-            final Scope scope,
+            final PbsFlowExpressionContext context) {
-            final TypeView expectedType,
+        final var scope = context.scope();
-            final TypeView returnType,
+        final var expectedType = context.expectedType();
-            final String resultErrorName,
+        final var returnType = context.returnType();
-            final TypeView receiverType,
+        final var resultErrorName = context.resultErrorName();
-            final Model model,
+        final var receiverType = context.receiverType();
-            final DiagnosticSink diagnostics,
+        final var model = context.model();
-            final ExprUse use,
+        final var diagnostics = context.diagnostics();
-            final boolean valueContext) {
+        final var use = context.use();
+        final var valueContext = context.valueContext();
         if (expression instanceof PbsAst.IntLiteralExpr) {
             return ExprResult.type(TypeView.intType());
         }
@@ -140,59 +137,21 @@ final class PbsFlowExpressionAnalyzer {
             return ExprResult.type(TypeView.unknown());
         }
         if (expression instanceof PbsAst.GroupExpr groupExpr) {
-            return analyzeExpressionInternal(
+            return analyzeExpressionInternal(groupExpr.expression(), context);
-                    groupExpr.expression(),
-                    scope,
-                    expectedType,
-                    returnType,
-                    resultErrorName,
-                    receiverType,
-                    model,
-                    diagnostics,
-                    use,
-                    valueContext);
         }
         if (expression instanceof PbsAst.TupleExpr tupleExpr) {
             final var fields = new ArrayList<TupleField>(tupleExpr.items().size());
             for (final var item : tupleExpr.items()) {
-                final var value = analyzeExpressionInternal(
+                final var value = analyzeValueExpression(item.expression(), context, null).type();
-                        item.expression(),
-                        scope,
-                        null,
-                        returnType,
-                        resultErrorName,
-                        receiverType,
-                        model,
-                        diagnostics,
-                        ExprUse.VALUE,
-                        true).type();
                 fields.add(new TupleField(item.label(), value));
             }
             return ExprResult.type(TypeView.tuple(fields));
         }
         if (expression instanceof PbsAst.BlockExpr blockExpr) {
-            return ExprResult.type(blockAnalyzer.analyze(
+            return ExprResult.type(analyzeBlock(blockExpr.block(), context, valueContext));
-                    blockExpr.block(),
-                    scope,
-                    returnType,
-                    resultErrorName,
-                    receiverType,
-                    model,
-                    diagnostics,
-                    valueContext));
         }
         if (expression instanceof PbsAst.UnaryExpr unaryExpr) {
-            final var operand = analyzeExpressionInternal(
+            final var operand = analyzeValueExpression(unaryExpr.expression(), context, null).type();
-                    unaryExpr.expression(),
-                    scope,
-                    null,
-                    returnType,
-                    resultErrorName,
-                    receiverType,
-                    model,
-                    diagnostics,
-                    ExprUse.VALUE,
-                    true).type();
             if ("!".equals(unaryExpr.operator()) || "not".equals(unaryExpr.operator())) {
                 return ExprResult.type(TypeView.bool());
             }
@@ -202,75 +161,23 @@ final class PbsFlowExpressionAnalyzer {
             return ExprResult.type(TypeView.unknown());
         }
         if (expression instanceof PbsAst.BinaryExpr binaryExpr) {
-            final var left = analyzeExpressionInternal(
+            final var left = analyzeValueExpression(binaryExpr.left(), context, null).type();
-                    binaryExpr.left(),
+            final var right = analyzeValueExpression(binaryExpr.right(), context, null).type();
-                    scope,
-                    null,
-                    returnType,
-                    resultErrorName,
-                    receiverType,
-                    model,
-                    diagnostics,
-                    ExprUse.VALUE,
-                    true).type();
-            final var right = analyzeExpressionInternal(
-                    binaryExpr.right(),
-                    scope,
-                    null,
-                    returnType,
-                    resultErrorName,
-                    receiverType,
-                    model,
-                    diagnostics,
-                    ExprUse.VALUE,
-                    true).type();
             return ExprResult.type(typeOps.inferBinaryResult(binaryExpr.operator(), left, right));
         }
         if (expression instanceof PbsAst.MemberExpr memberExpr) {
             return analyzeMemberExpression(
                     memberExpr,
-                    scope,
+                    context);
-                    returnType,
-                    resultErrorName,
-                    receiverType,
-                    model,
-                    diagnostics,
-                    use);
         }
         if (expression instanceof PbsAst.CallExpr callExpr) {
-            return analyzeCallExpression(
+            return analyzeCallExpression(callExpr, context);
-                    callExpr,
-                    scope,
-                    expectedType,
-                    returnType,
-                    resultErrorName,
-                    receiverType,
-                    model,
-                    diagnostics);
         }
         if (expression instanceof PbsAst.ApplyExpr applyExpr) {
-            return analyzeApplyExpression(
+            return analyzeApplyExpression(applyExpr, context);
-                    applyExpr,
-                    scope,
-                    expectedType,
-                    returnType,
-                    resultErrorName,
-                    receiverType,
-                    model,
-                    diagnostics);
         }
         if (expression instanceof PbsAst.IfExpr ifExpr) {
-            final var condition = analyzeExpressionInternal(
+            final var condition = analyzeValueExpression(ifExpr.condition(), context, TypeView.bool()).type();
-                    ifExpr.condition(),
-                    scope,
-                    TypeView.bool(),
-                    returnType,
-                    resultErrorName,
-                    receiverType,
-                    model,
-                    diagnostics,
-                    ExprUse.VALUE,
-                    true).type();
             if (!typeOps.isBool(condition)) {
                 p.studio.compiler.source.diagnostics.Diagnostics.error(diagnostics, 
                         PbsSemanticsErrors.E_SEM_IF_NON_BOOL_CONDITION.name(),
@@ -278,18 +185,8 @@ final class PbsFlowExpressionAnalyzer {
                         ifExpr.condition().span());
             }
 
-            final var thenType = blockAnalyzer.analyze(ifExpr.thenBlock(), scope, returnType, resultErrorName, receiverType, model, diagnostics, true);
+            final var thenType = analyzeBlock(ifExpr.thenBlock(), context, true);
-            final var elseType = analyzeExpressionInternal(
+            final var elseType = analyzeValueExpression(ifExpr.elseExpression(), context, expectedType).type();
-                    ifExpr.elseExpression(),
-                    scope,
-                    expectedType,
-                    returnType,
-                    resultErrorName,
-                    receiverType,
-                    model,
-                    diagnostics,
-                    ExprUse.VALUE,
-                    true).type();
 
             if (!typeOps.compatible(thenType, elseType)) {
                 p.studio.compiler.source.diagnostics.Diagnostics.error(diagnostics, 
@@ -301,60 +198,21 @@ final class PbsFlowExpressionAnalyzer {
             return ExprResult.type(thenType);
         }
         if (expression instanceof PbsAst.SwitchExpr switchExpr) {
-            return ExprResult.type(analyzeSwitchExpression(
+            return ExprResult.type(analyzeSwitchExpression(switchExpr, context));
-                    switchExpr,
-                    scope,
-                    expectedType,
-                    returnType,
-                    resultErrorName,
-                    receiverType,
-                    model,
-                    diagnostics,
-                    valueContext));
         }
         if (expression instanceof PbsAst.ElseExpr elseExpr) {
-            final var optional = analyzeExpressionInternal(
+            final var optional = analyzeValueExpression(elseExpr.optionalExpression(), context, null).type();
-                    elseExpr.optionalExpression(),
-                    scope,
-                    null,
-                    returnType,
-                    resultErrorName,
-                    receiverType,
-                    model,
-                    diagnostics,
-                    ExprUse.VALUE,
-                    true).type();
             if (optional.kind() != Kind.OPTIONAL) {
                 p.studio.compiler.source.diagnostics.Diagnostics.error(diagnostics, 
                         PbsSemanticsErrors.E_SEM_ELSE_NON_OPTIONAL_LEFT.name(),
                         "Left operand of 'else' must have optional type",
                         elseExpr.optionalExpression().span());
-                analyzeExpressionInternal(
+                analyzeValueExpression(elseExpr.fallbackExpression(), context, null);
-                        elseExpr.fallbackExpression(),
-                        scope,
-                        null,
-                        returnType,
-                        resultErrorName,
-                        receiverType,
-                        model,
-                        diagnostics,
-                        ExprUse.VALUE,
-                        true);
                 return ExprResult.type(TypeView.unknown());
             }
 
             final var payload = optional.inner();
-            final var fallback = analyzeExpressionInternal(
+            final var fallback = analyzeValueExpression(elseExpr.fallbackExpression(), context, payload).type();
-                    elseExpr.fallbackExpression(),
-                    scope,
-                    payload,
-                    returnType,
-                    resultErrorName,
-                    receiverType,
-                    model,
-                    diagnostics,
-                    ExprUse.VALUE,
-                    true).type();
             if (!typeOps.compatible(fallback, payload)) {
                 p.studio.compiler.source.diagnostics.Diagnostics.error(diagnostics, 
                         PbsSemanticsErrors.E_SEM_ELSE_FALLBACK_TYPE_MISMATCH.name(),
@@ -364,17 +222,7 @@ final class PbsFlowExpressionAnalyzer {
             return ExprResult.type(payload);
         }
         if (expression instanceof PbsAst.PropagateExpr propagateExpr) {
-            final var source = analyzeExpressionInternal(
+            final var source = analyzeValueExpression(propagateExpr.expression(), context, null).type();
-                    propagateExpr.expression(),
-                    scope,
-                    null,
-                    returnType,
-                    resultErrorName,
-                    receiverType,
-                    model,
-                    diagnostics,
-                    ExprUse.VALUE,
-                    true).type();
             if (source.kind() != Kind.RESULT) {
                 p.studio.compiler.source.diagnostics.Diagnostics.error(diagnostics, 
                         PbsSemanticsErrors.E_SEM_RESULT_PROPAGATE_NON_RESULT.name(),
@@ -392,14 +240,7 @@ final class PbsFlowExpressionAnalyzer {
             return ExprResult.type(source.inner());
         }
         if (expression instanceof PbsAst.HandleExpr handleExpr) {
-            return ExprResult.type(analyzeHandleExpression(
+            return ExprResult.type(analyzeHandleExpression(handleExpr, context));
-                    handleExpr,
-                    scope,
-                    returnType,
-                    resultErrorName,
-                    receiverType,
-                    model,
-                    diagnostics));
         }
         if (expression instanceof PbsAst.NoneExpr noneExpr) {
             if (expectedType == null || expectedType.kind() != Kind.OPTIONAL) {
@@ -415,31 +256,11 @@ final class PbsFlowExpressionAnalyzer {
             final var payloadExpected = expectedType != null && expectedType.kind() == Kind.OPTIONAL
                     ? expectedType.inner()
                     : null;
-            final var payload = analyzeExpressionInternal(
+            final var payload = analyzeValueExpression(someExpr.value(), context, payloadExpected).type();
-                    someExpr.value(),
-                    scope,
-                    payloadExpected,
-                    returnType,
-                    resultErrorName,
-                    receiverType,
-                    model,
-                    diagnostics,
-                    ExprUse.VALUE,
-                    true).type();
             return ExprResult.type(TypeView.optional(payloadExpected == null ? payload : payloadExpected));
         }
         if (expression instanceof PbsAst.BindExpr bindExpr) {
-            final var contextType = analyzeExpressionInternal(
+            final var contextType = analyzeValueExpression(bindExpr.contextExpression(), context, null).type();
-                    bindExpr.contextExpression(),
-                    scope,
-                    null,
-                    returnType,
-                    resultErrorName,
-                    receiverType,
-                    model,
-                    diagnostics,
-                    ExprUse.VALUE,
-                    true).type();
             if (expectedType == null || expectedType.kind() != Kind.CALLBACK) {
                 return ExprResult.type(TypeView.unknown());
             }
@@ -491,17 +312,7 @@ final class PbsFlowExpressionAnalyzer {
             return ExprResult.type(TypeView.unknown());
         }
         if (expression instanceof PbsAst.AsExpr asExpr) {
-            analyzeExpressionInternal(
+            analyzeValueExpression(asExpr.expression(), context, null);
-                    asExpr.expression(),
-                    scope,
-                    null,
-                    returnType,
-                    resultErrorName,
-                    receiverType,
-                    model,
-                    diagnostics,
-                    ExprUse.VALUE,
-                    true);
             if (model.contracts.containsKey(asExpr.contractName())) {
                 return ExprResult.type(TypeView.contract(asExpr.contractName()));
             }
@@ -513,17 +324,7 @@ final class PbsFlowExpressionAnalyzer {
                     PbsSemanticsErrors.E_SEM_RESULT_FLOW_INVALID_POSITION.name(),
                     "'ok(...)' is only allowed in result return flow and handle arm terminals",
                     okExpr.span());
-            analyzeExpressionInternal(
+            analyzeValueExpression(okExpr.value(), context, null);
-                    okExpr.value(),
-                    scope,
-                    null,
-                    returnType,
-                    resultErrorName,
-                    receiverType,
-                    model,
-                    diagnostics,
-                    ExprUse.VALUE,
-                    true);
             return ExprResult.type(TypeView.unknown());
         }
         if (expression instanceof PbsAst.ErrExpr errExpr) {
@@ -539,54 +340,18 @@ final class PbsFlowExpressionAnalyzer {
 
     private ExprResult analyzeCallExpression(
             final PbsAst.CallExpr callExpr,
-            final Scope scope,
+            final PbsFlowExpressionContext context) {
-            final TypeView expectedType,
+        final var callee = analyzeTargetExpression(callExpr.callee(), context, ExprUse.CALL_TARGET);
-            final TypeView returnType,
-            final String resultErrorName,
-            final TypeView receiverType,
-            final Model model,
-            final DiagnosticSink diagnostics) {
-        final var callee = analyzeExpressionInternal(
-                callExpr.callee(),
-                scope,
-                null,
-                returnType,
-                resultErrorName,
-                receiverType,
-                model,
-                diagnostics,
-                ExprUse.CALL_TARGET,
-                true);
 
         final TypeView argumentType;
         if (callExpr.arguments().isEmpty()) {
             argumentType = TypeView.unit();
         } else if (callExpr.arguments().size() == 1) {
-            argumentType = analyzeExpressionInternal(
+            argumentType = analyzeValueExpression(callExpr.arguments().getFirst(), context, null).type();
-                    callExpr.arguments().getFirst(),
-                    scope,
-                    null,
-                    returnType,
-                    resultErrorName,
-                    receiverType,
-                    model,
-                    diagnostics,
-                    ExprUse.VALUE,
-                    true).type();
         } else {
             final var fields = new ArrayList<TupleField>(callExpr.arguments().size());
             for (final var argument : callExpr.arguments()) {
-                final var itemType = analyzeExpressionInternal(
+                final var itemType = analyzeValueExpression(argument, context, null).type();
-                        argument,
-                        scope,
-                        null,
-                        returnType,
-                        resultErrorName,
-                        receiverType,
-                        model,
-                        diagnostics,
-                        ExprUse.VALUE,
-                        true).type();
                 fields.add(new TupleField(null, itemType));
             }
             argumentType = TypeView.tuple(fields);
@@ -597,49 +362,23 @@ final class PbsFlowExpressionAnalyzer {
                 callExpr.callee().span(),
                 callee,
                 argumentType,
-                expectedType,
+                context.expectedType(),
-                diagnostics);
+                context.diagnostics());
     }
 
     private ExprResult analyzeApplyExpression(
             final PbsAst.ApplyExpr applyExpr,
-            final Scope scope,
+            final PbsFlowExpressionContext context) {
-            final TypeView expectedType,
+        final var callee = analyzeTargetExpression(applyExpr.callee(), context, ExprUse.APPLY_TARGET);
-            final TypeView returnType,
+        final var argument = analyzeValueExpression(applyExpr.argument(), context, null).type();
-            final String resultErrorName,
-            final TypeView receiverType,
-            final Model model,
-            final DiagnosticSink diagnostics) {
-        final var callee = analyzeExpressionInternal(
-                applyExpr.callee(),
-                scope,
-                null,
-                returnType,
-                resultErrorName,
-                receiverType,
-                model,
-                diagnostics,
-                ExprUse.APPLY_TARGET,
-                true);
-        final var argument = analyzeExpressionInternal(
-                applyExpr.argument(),
-                scope,
-                null,
-                returnType,
-                resultErrorName,
-                receiverType,
-                model,
-                diagnostics,
-                ExprUse.VALUE,
-                true).type();
 
         return resolveCallableApplication(
                 applyExpr.span(),
                 applyExpr.callee().span(),
                 callee,
                 argument,
-                expectedType,
+                context.expectedType(),
-                diagnostics);
+                context.diagnostics());
     }
 
     private ExprResult resolveCallableApplication(
@@ -702,24 +441,12 @@ final class PbsFlowExpressionAnalyzer {
 
     private ExprResult analyzeMemberExpression(
             final PbsAst.MemberExpr memberExpr,
-            final Scope scope,
+            final PbsFlowExpressionContext context) {
-            final TypeView returnType,
+        final var receiver = analyzeValueExpression(memberExpr.receiver(), context, null).type();
-            final String resultErrorName,
+        final var model = context.model();
-            final TypeView receiverType,
+        final var diagnostics = context.diagnostics();
-            final Model model,
+        final var receiverType = context.receiverType();
-            final DiagnosticSink diagnostics,
+        final var use = context.use();
-            final ExprUse use) {
-        final var receiver = analyzeExpressionInternal(
-                memberExpr.receiver(),
-                scope,
-                null,
-                returnType,
-                resultErrorName,
-                receiverType,
-                model,
-                diagnostics,
-                ExprUse.VALUE,
-                true).type();
 
         if (receiver.kind() == Kind.TYPE_REF) {
             final var enumCases = model.enums.get(receiver.name());
@@ -857,25 +584,10 @@ final class PbsFlowExpressionAnalyzer {
 
     private TypeView analyzeSwitchExpression(
             final PbsAst.SwitchExpr switchExpr,
-            final Scope scope,
+            final PbsFlowExpressionContext context) {
-            final TypeView expectedType,
+        final var model = context.model();
-            final TypeView returnType,
+        final var diagnostics = context.diagnostics();
-            final String resultErrorName,
+        final var selector = analyzeValueExpression(switchExpr.selector(), context, null).type();
-            final TypeView receiverType,
-            final Model model,
-            final DiagnosticSink diagnostics,
-            final boolean valueContext) {
-        final var selector = analyzeExpressionInternal(
-                switchExpr.selector(),
-                scope,
-                null,
-                returnType,
-                resultErrorName,
-                receiverType,
-                model,
-                diagnostics,
-                ExprUse.VALUE,
-                true).type();
 
         final var selectorComparable = typeOps.isScalarComparable(selector) || selector.kind() == Kind.ENUM;
         if (!selectorComparable) {
@@ -928,15 +640,7 @@ final class PbsFlowExpressionAnalyzer {
                         arm.pattern().span());
             }
 
-            final var currentArmType = blockAnalyzer.analyze(
+            final var currentArmType = analyzeBlock(arm.block(), context, true);
-                    arm.block(),
-                    scope,
-                    returnType,
-                    resultErrorName,
-                    receiverType,
-                    model,
-                    diagnostics,
-                    true);
             if (armType == null) {
                 armType = currentArmType;
             } else if (!typeOps.compatible(currentArmType, armType)) {
@@ -947,7 +651,7 @@ final class PbsFlowExpressionAnalyzer {
             }
         }
 
-        if (valueContext && !hasWildcard) {
+        if (context.valueContext() && !hasWildcard) {
             var exhaustive = false;
             if (selector.kind() == Kind.ENUM) {
                 final var allCases = model.enums.get(selector.name());
@@ -974,8 +678,8 @@ final class PbsFlowExpressionAnalyzer {
         if (armType == null) {
             return TypeView.unit();
         }
-        if (expectedType != null && typeOps.compatible(armType, expectedType)) {
+        if (context.expectedType() != null && typeOps.compatible(armType, context.expectedType())) {
-            return expectedType;
+            return context.expectedType();
         }
         return armType;
     }
@@ -1037,23 +741,11 @@ final class PbsFlowExpressionAnalyzer {
 
     private TypeView analyzeHandleExpression(
             final PbsAst.HandleExpr handleExpr,
-            final Scope scope,
+            final PbsFlowExpressionContext context) {
-            final TypeView returnType,
+        final var model = context.model();
-            final String resultErrorName,
+        final var diagnostics = context.diagnostics();
-            final TypeView receiverType,
+        final var resultErrorName = context.resultErrorName();
-            final Model model,
+        final var sourceType = analyzeValueExpression(handleExpr.value(), context, null).type();
-            final DiagnosticSink diagnostics) {
-        final var sourceType = analyzeExpressionInternal(
-                handleExpr.value(),
-                scope,
-                null,
-                returnType,
-                resultErrorName,
-                receiverType,
-                model,
-                diagnostics,
-                ExprUse.VALUE,
-                true).type();
         if (sourceType.kind() != Kind.RESULT) {
             p.studio.compiler.source.diagnostics.Diagnostics.error(diagnostics, 
                     PbsSemanticsErrors.E_SEM_HANDLE_NON_RESULT.name(),
@@ -1107,11 +799,8 @@ final class PbsFlowExpressionAnalyzer {
             }
             analyzeHandleBlockArm(
                     arm,
-                    scope,
+                    context,
                     sourcePayloadType,
-                    returnType,
-                    resultErrorName,
-                    receiverType,
                     model,
                     diagnostics);
         }
@@ -1128,13 +817,14 @@ final class PbsFlowExpressionAnalyzer {
 
     private void analyzeHandleBlockArm(
             final PbsAst.HandleArm arm,
-            final Scope scope,
+            final PbsFlowExpressionContext context,
             final TypeView sourcePayloadType,
-            final TypeView returnType,
-            final String resultErrorName,
-            final TypeView receiverType,
             final Model model,
             final DiagnosticSink diagnostics) {
+        final var returnType = context.returnType();
+        final var resultErrorName = context.resultErrorName();
+        final var receiverType = context.receiverType();
+        final var scope = context.scope();
         if (arm.block() == null) {
             p.studio.compiler.source.diagnostics.Diagnostics.error(diagnostics,
                     PbsSemanticsErrors.E_SEM_HANDLE_ARM_TERMINAL_INVALID.name(),
@@ -1147,15 +837,7 @@ final class PbsFlowExpressionAnalyzer {
         final var terminal = unwrapGroup(block.tailExpression());
         if (terminal instanceof PbsAst.OkExpr okExpr) {
             final var payloadBlock = new PbsAst.Block(block.statements(), okExpr.value(), block.span());
-            final var actualPayloadType = blockAnalyzer.analyze(
+            final var actualPayloadType = analyzeBlock(payloadBlock, context, true);
-                    payloadBlock,
-                    scope,
-                    returnType,
-                    resultErrorName,
-                    receiverType,
-                    model,
-                    diagnostics,
-                    true);
             if (!typeOps.compatible(actualPayloadType, sourcePayloadType)) {
                 p.studio.compiler.source.diagnostics.Diagnostics.error(diagnostics,
                         PbsSemanticsErrors.E_SEM_RESULT_OK_PAYLOAD_MISMATCH.name(),
@@ -1167,15 +849,7 @@ final class PbsFlowExpressionAnalyzer {
 
         if (terminal instanceof PbsAst.ErrExpr errExpr) {
             final var statementsOnly = new PbsAst.Block(block.statements(), null, block.span());
-            blockAnalyzer.analyze(
+            analyzeBlock(statementsOnly, context, false);
-                    statementsOnly,
-                    scope,
-                    returnType,
-                    resultErrorName,
-                    receiverType,
-                    model,
-                    diagnostics,
-                    false);
             if (resultErrorName != null && !matchesTargetError(errExpr.errorPath(), resultErrorName, model)) {
                 p.studio.compiler.source.diagnostics.Diagnostics.error(diagnostics,
                         PbsSemanticsErrors.E_SEM_RESULT_ERROR_LABEL_INVALID.name(),
@@ -1187,25 +861,9 @@ final class PbsFlowExpressionAnalyzer {
 
         if (block.tailExpression() == null) {
             final var statementsOnly = new PbsAst.Block(block.statements(), null, block.span());
-            blockAnalyzer.analyze(
+            analyzeBlock(statementsOnly, context, false);
-                    statementsOnly,
-                    scope,
-                    returnType,
-                    resultErrorName,
-                    receiverType,
-                    model,
-                    diagnostics,
-                    false);
         } else {
-            blockAnalyzer.analyze(
+            analyzeBlock(block, context, true);
-                    block,
-                    scope,
-                    returnType,
-                    resultErrorName,
-                    receiverType,
-                    model,
-                    diagnostics,
-                    true);
         }
         p.studio.compiler.source.diagnostics.Diagnostics.error(diagnostics,
                 PbsSemanticsErrors.E_SEM_HANDLE_ARM_TERMINAL_INVALID.name(),
@@ -1236,4 +894,41 @@ final class PbsFlowExpressionAnalyzer {
         return expression;
     }
 
+    private ExprResult analyzeValueExpression(
+            final PbsAst.Expression expression,
+            final PbsFlowExpressionContext context,
+            final TypeView expectedType) {
+        return analyzeExpressionInternal(
+                expression,
+                context.withExpectedType(expectedType)
+                        .withUse(ExprUse.VALUE)
+                        .withValueContext(true));
+    }
+
+    private ExprResult analyzeTargetExpression(
+            final PbsAst.Expression expression,
+            final PbsFlowExpressionContext context,
+            final ExprUse use) {
+        return analyzeExpressionInternal(
+                expression,
+                context.withExpectedType(null)
+                        .withUse(use)
+                        .withValueContext(true));
+    }
+
+    private TypeView analyzeBlock(
+            final PbsAst.Block block,
+            final PbsFlowExpressionContext context,
+            final boolean valueContext) {
+        return context.blockAnalyzer().analyze(
+                block,
+                context.scope(),
+                context.returnType(),
+                context.resultErrorName(),
+                context.receiverType(),
+                context.model(),
+                context.diagnostics(),
+                valueContext);
+    }
+
 }

prometeu-compiler/frontends/prometeu-frontend-pbs/src/main/java/p/studio/compiler/pbs/semantics/PbsFlowExpressionContext.java

@@ -0,0 +1,125 @@
+package p.studio.compiler.pbs.semantics;
+
+import p.studio.compiler.source.diagnostics.DiagnosticSink;
+import p.studio.compiler.pbs.semantics.PbsFlowSemanticSupport.ExprUse;
+import p.studio.compiler.pbs.semantics.PbsFlowSemanticSupport.Model;
+import p.studio.compiler.pbs.semantics.PbsFlowSemanticSupport.Scope;
+import p.studio.compiler.pbs.semantics.PbsFlowSemanticSupport.TypeView;
+
+final class PbsFlowExpressionContext {
+    private final Scope scope;
+    private final TypeView expectedType;
+    private final TypeView returnType;
+    private final String resultErrorName;
+    private final TypeView receiverType;
+    private final Model model;
+    private final DiagnosticSink diagnostics;
+    private final ExprUse use;
+    private final boolean valueContext;
+    private final PbsFlowExpressionAnalyzer.BlockAnalyzer blockAnalyzer;
+
+    PbsFlowExpressionContext(
+            final Scope scope,
+            final TypeView expectedType,
+            final TypeView returnType,
+            final String resultErrorName,
+            final TypeView receiverType,
+            final Model model,
+            final DiagnosticSink diagnostics,
+            final ExprUse use,
+            final boolean valueContext,
+            final PbsFlowExpressionAnalyzer.BlockAnalyzer blockAnalyzer) {
+        this.scope = scope;
+        this.expectedType = expectedType;
+        this.returnType = returnType;
+        this.resultErrorName = resultErrorName;
+        this.receiverType = receiverType;
+        this.model = model;
+        this.diagnostics = diagnostics;
+        this.use = use;
+        this.valueContext = valueContext;
+        this.blockAnalyzer = blockAnalyzer;
+    }
+
+    Scope scope() {
+        return scope;
+    }
+
+    TypeView expectedType() {
+        return expectedType;
+    }
+
+    TypeView returnType() {
+        return returnType;
+    }
+
+    String resultErrorName() {
+        return resultErrorName;
+    }
+
+    TypeView receiverType() {
+        return receiverType;
+    }
+
+    Model model() {
+        return model;
+    }
+
+    DiagnosticSink diagnostics() {
+        return diagnostics;
+    }
+
+    ExprUse use() {
+        return use;
+    }
+
+    boolean valueContext() {
+        return valueContext;
+    }
+
+    PbsFlowExpressionAnalyzer.BlockAnalyzer blockAnalyzer() {
+        return blockAnalyzer;
+    }
+
+    PbsFlowExpressionContext withExpectedType(final TypeView nextExpectedType) {
+        return new PbsFlowExpressionContext(
+                scope,
+                nextExpectedType,
+                returnType,
+                resultErrorName,
+                receiverType,
+                model,
+                diagnostics,
+                use,
+                valueContext,
+                blockAnalyzer);
+    }
+
+    PbsFlowExpressionContext withUse(final ExprUse nextUse) {
+        return new PbsFlowExpressionContext(
+                scope,
+                expectedType,
+                returnType,
+                resultErrorName,
+                receiverType,
+                model,
+                diagnostics,
+                nextUse,
+                valueContext,
+                blockAnalyzer);
+    }
+
+    PbsFlowExpressionContext withValueContext(final boolean nextValueContext) {
+        return new PbsFlowExpressionContext(
+                scope,
+                expectedType,
+                returnType,
+                resultErrorName,
+                receiverType,
+                model,
+                diagnostics,
+                use,
+                nextValueContext,
+                blockAnalyzer);
+    }
+}