presto-main/src/main/java/io/prestosql/metadata/SignatureBinder.java/FunctionSolver/FunctionSolver
class FunctionSolver:        public FunctionSolver(
                List<TypeSignature> formalLambdaArgumentsTypeSignature,
                TypeSignature formalLambdaReturnTypeSignature,
                TypeSignatureProvider typeSignatureProvider)
        {
            this.formalLambdaArgumentsTypeSignature = formalLambdaArgumentsTypeSignature;
            this.formalLambdaReturnTypeSignature = formalLambdaReturnTypeSignature;
            this.typeSignatureProvider = typeSignatureProvider;
        }