• I want to implement a base contract that multiple contracts should implement.
  • I decided to use "#[openbrush::trait_definition]" because "[#ink(message)]" cannot be added in the normal implementation of traits.
  • However, traits declared in another library crate cannot be referenced.
  • If you remove "#[openbrush::trait_definition]" as a trial, you can refer to it.
  • Could you tell me what is wrong?

definition of trait: commons/lib.rs

    pub trait Destination {
        fn execute_function(&mut self) -> Result<(), ()>;

use of trait: destination_base/lib.rs

mod destination_base {
    use commons::Destination;    
    /// Defines the storage of your contract.
    /// Add new fields to the below struct in order
    /// to add new static storage fields to your contract.
    pub struct DestinationBase {
        /// Stores a single `bool` value on the storage.
        value: bool,

    impl Destination for DestinationBase {
        fn execute_function(&mut self) -> Result<(),()> {


    Checking destination_base v0.1.0 (/Users/shin.takahashi/develop/work/delegate_test2/contracts/destination_base)
error[E0432]: unresolved import `commons::Destination`
 --> src/lib.rs:9:9
9 |     use commons::Destination;    
  |         ^^^^^^^^^^^^^^^^^^^^ no `Destination` in the root

  • can you share github link to your code?
    – kriko.eth
    Jan 7, 2023 at 14:59
  • I guess you haven't include commons = { path = "../../commons", default-features = false } inside dependencies of destination_base cargo.toml. also don't forgot to include "commons/std" inside std
    – Ganesh11
    Jan 7, 2023 at 15:54
  • Thank you. I tried but The situation remains the same.I made a similar sample and pushed it below, could you check it out? github.com/realtakahashi/trait_test Jan 7, 2023 at 23:12

2 Answers 2


I have added contract/logics in contracts because your contract/commons is different. I think you have generated this folder using cargo new commons? instead you can use cargo contract new logics command to create new contract. I have fixed your code. Include logics = { path = "../logics", default-features = false, features = ["ink-as-dependency"] } inside dependencies of test/Cargo.toml and include "commons/std" inside std. Aslo don't forgot to add "rlib" to the crate-type options under "cdylib" in your logics/Cargo.toml. I have included github.com repo of the code.

  • Thank you for your proposal of the solution. Your sample can be compiled, but the "execute_function" is not a contract function. I want to call "execute_function" as a contract function like the "flip" function. Is it possible? Jan 10, 2023 at 12:30
  • Do you mean execuate_function Methods flagged with #[ink(message)] in impl Base for test {}?
    – Ganesh11
    Jan 10, 2023 at 14:29
  • yes,right. When I added "#[ink(message)]" to execute function, I got errors. Jan 10, 2023 at 22:15
  • 1
    @s.Takahashi Instead of #[openbrush::trait_definition] if you use [#[ink::trait_defination]] it solves. I don't know why exactly it doesn't work with openbrush. You can view changes here
    – Ganesh11
    Jan 14, 2023 at 11:29
  • 1
    oh wow it fix, thank you @s.Takahashi
    – Ganesh11
    Jan 16, 2023 at 2:08

I asked on Element's BrushFam. And "Dominik | Brushfam" told me. To fix this error you need to import everything. As below.

use commons::*;

trait_definition macro generates some code which is then used by the ink_contract so you need to expose that too in order to impl that trait for your contract

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