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

mod crowd_funding {
    use ink::storage::Mapping;
    #[derive(scale::Decode, scale::Encode)]
        feature = "std",
        derive(scale_info::TypeInfo, ink::storage::traits::StorageLayout)

    pub struct IndividualFundMe {
        account_id: AccountId,
        go_fund_id: u64,
        name: String,
        reason_for_fund: String,
        amount_needed: Balance,
        amount_gotten: Balance,
        status: bool,
        donators: Vec<AccountId>

    pub struct CrowdFunding {
        go_funds: Mapping<AccountId, IndividualFundMe>,
        all_go_funds: Vec<IndividualFundMe>,
        successfull_go_funds: Vec<IndividualFundMe>,
        go_fund_id: u64

    impl CrowdFunding {
        pub fn new() -> Self {
            Self {
                go_funds: Mapping::new(),
                all_go_funds: Vec::new(),
                successfull_go_funds: Vec::new(),
                go_fund_id: 1

        pub fn create_crowdfund(&mut self, _name: String, _reason_for_fund: String, _amount_needed: Balance)  {
            let new_gofund =  IndividualFundMe {
                account_id: self.env().caller(),
                go_fund_id: self.go_fund_id,
                name: _name.clone(),
                reason_for_fund: _reason_for_fund.clone(),
                amount_needed: _amount_needed,
                amount_gotten: 0,
                status: false,
                donators: Vec::new()
            self.go_funds.insert(self.env().caller(), &new_gofund);
            self.go_fund_id += 1;

Below is the compiler error

`IndividualFundMe` doesn't implement `Debug`
the trait `Debug` is not implemented for `IndividualFundMe`
add `#[derive(Debug)]` to `IndividualFundMe` or manually `impl Debug for IndividualFundMe`
the trait `Debug` is implemented for `Vec<T, A>`
  • Please paste the compile error message. Mar 29, 2023 at 11:34
  • 1
    use ink::prelude::{string::String, vec::Vec}; add this
    – Ganesh11
    Mar 29, 2023 at 11:36
  • I added this already Ganesh11 but it still complains
    – Mite
    Mar 29, 2023 at 14:37

1 Answer 1


You need to import: use ink::prelude::vec::Vec; in the contract's module.

You also need to import use ink::prelude::string::String; for strings.

These are the preludes that implement necessary traits to be stored.

  • Edited just now, you don't actually need to derive Debug, just import these preludes. Mar 29, 2023 at 16:26

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