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PSP34 Enumerable

This example shows how you can reuse the implementation of PSP34 token with PSP34Enumerable extension.

First, you should implement basic version of PSP34.

Step 1: Add imports and enable unstable feature​

Import everything from openbrush::contracts::psp34::extensions::enumerable.

#![cfg_attr(not(feature = "std"), no_std)]
#![feature(min_specialization)]

#[openbrush::contract]
pub mod my_psp34 {
    use openbrush::contracts::psp34::extensions::enumerable::*;
...

Step 2: Define storage​

Pass enumerable::Balances into psp34::Data to be able to use PSP34Enumerable extension in your PSP34 implementation.

#[derive(Default, SpreadAllocate, Storage)]
#[ink(storage)]
pub struct Contract {
    #[storage_field]
    psp34: psp34::Data<enumerable::Balances>,
}

Step 3: Inherit logic​

Inherit implementation of the PSP34Enumerable trait. You can customize (override) methods in this impl block.

impl PSP34Enumerable for Contract {}

Final code​

#![cfg_attr(not(feature = "std"), no_std)]
#![feature(min_specialization)]

#[openbrush::contract]
pub mod my_psp34_enumerable {
    use ink_storage::traits::SpreadAllocate;
    use openbrush::{
        contracts::psp34::extensions::enumerable::*,
        traits::Storage,
    };

    #[derive(Default, SpreadAllocate, Storage)]
    #[ink(storage)]
    pub struct Contract {
        #[storage_field]
        psp34: psp34::Data<enumerable::Balances>,
    }

    impl PSP34 for Contract {}
    impl PSP34Enumerable for Contract {}

    impl Contract {
        #[ink(constructor)]
        pub fn new() -> Self {
            ink_lang::codegen::initialize_contract(|_instance: &mut Self| {})
        }
    }
}

And that's it! Your PSP34 is now extended by the PSP34Enumerable extension and ready to use its functions! You can check an example of the usage of PSP34 Enumerable.

You can also check the documentation for the basic implementation of PSP34.