presto-main/src/main/java/io/prestosql/sql/planner/LogicalPlanner.java/LogicalPlanner/buildLambdaDeclarationToSymbolMap
class LogicalPlanner:    private static Map<NodeRef<LambdaArgumentDeclaration>, Symbol> buildLambdaDeclarationToSymbolMap(Analysis analysis, SymbolAllocator symbolAllocator)
    {
        Map<NodeRef<LambdaArgumentDeclaration>, Symbol> resultMap = new LinkedHashMap<>();
        for (Entry<NodeRef<Expression>, Type> entry : analysis.getTypes().entrySet()) {
            if (!(entry.getKey().getNode() instanceof LambdaArgumentDeclaration)) {
                continue;
            }
            NodeRef<LambdaArgumentDeclaration> lambdaArgumentDeclaration = NodeRef.of((LambdaArgumentDeclaration) entry.getKey().getNode());
            if (resultMap.containsKey(lambdaArgumentDeclaration)) {
                continue;
            }
            resultMap.put(lambdaArgumentDeclaration, symbolAllocator.newSymbol(lambdaArgumentDeclaration.getNode(), entry.getValue()));
        }
        return resultMap;
    }