program-examples

            },            signer        ),        AuthorityType::MintTokens,        None    )?;     Ok(())} #[derive(Accounts)]pub struct MintNft<'info> {    #[account(mut)]    pub signer: Signer<'info>,    pub system_program: Program<'info, System>,    pub token_program: Program<'info, Token2022>,    /// CHECK: We will create this one for the user    #[account(mut)]    pub token_account: AccountInfo<'info>,    #[account(mut)]    pub mint: Signer<'info>,    pub rent: Sysvar<'info, Rent>,    pub associated_token_program: Program<'info, AssociatedToken>,    #[account(init_if_needed, seeds = [b"nft_authority".as_ref()], bump, space = 8, payer = signer)]

1. Line 172 AuthorityType::MintTokens,: Mints new tokens. The mint authority must sign.
2. Line 182 pub signer: Signer<'info>,: Requires this account to have signed the transaction.
3. Line 184 pub token_program: Program<'info, Token2022>,: Targets the Token-2022 program instead of the original Token Program.
4. Line 192 #[account(init_if_needed, seeds = [b"nft_authority".as_ref()], bump, space = 8, payer = si: Declares the PDA seeds. Anchor re-derives the address and rejects the account if it doesn't match.
5. Line 192 #[account(init_if_needed, seeds = [b"nft_authority".as_ref()], bump, space = 8, payer = si: Uses the bump seed, the extra byte that pushes the derived address off the ed25519 curve.
6. Line 192 #[account(init_if_needed, seeds = [b"nft_authority".as_ref()], bump, space = 8, payer = si: Creates the account only if it doesn't exist. Watch for re-initialisation bugs.
7. Line 192 #[account(init_if_needed, seeds = [b"nft_authority".as_ref()], bump, space = 8, payer = si: Creates and pays for a new account. Space and payer must be specified.

         let computed_root = compute_merkle_root(&leaf, &hashes, index)?;         require!(computed_root.eq(&airdrop_state.merkle_root), ClaimError::InvalidProof);         let new_amount_claimed = airdrop_state.amount_claimed.checked_add(amount).ok_or(ClaimError::AmountOverflow)?;        require!(new_amount_claimed <= airdrop_state.airdrop_amount, ClaimError::ClaimExceedsAirdrop);         let mint_key = ctx.accounts.mint.key().to_bytes();        let signer_seeds = &[b"merkle_tree".as_ref(), mint_key.as_ref(), &[airdrop_state.bump]];         transfer_checked(            CpiContext::new_with_signer(                ctx.accounts.token_program.key(),                TransferChecked {                    from: ctx.accounts.vault.to_account_info(),                    mint: ctx.accounts.mint.to_account_info(),                    to: ctx.accounts.signer_ata.to_account_info(),                    authority: airdrop_state.to_account_info(),                },                &[signer_seeds],            ),            amount,            ctx.accounts.mint.decimals,

1. Line 76 require!(computed_root.eq(&airdrop_state.merkle_root), ClaimError::InvalidProof);: An explicit validation that aborts the instruction with an error.
2. Line 78 let new_amount_claimed = airdrop_state.amount_claimed.checked_add(amount).ok_or(ClaimError: Uses checked arithmetic so overflow fails instead of wrapping.
3. Line 82 let signer_seeds = &[b"merkle_tree".as_ref(), mint_key.as_ref(), &[airdrop_state.bump]];: Declares the PDA seeds. Anchor re-derives the address and rejects the account if it doesn't match.
4. Line 82 let signer_seeds = &[b"merkle_tree".as_ref(), mint_key.as_ref(), &[airdrop_state.bump]];: Uses the bump seed, the extra byte that pushes the derived address off the ed25519 curve.
5. Line 84 transfer_checked(: A checked token transfer, which also verifies the mint and decimals.
6. Line 85 CpiContext::new_with_signer(: Makes a CPI signed by a PDA. The signer seeds prove the program controls that address.

        token_interface::mint_to(cpi_context, amount)?;        msg!("Mint Token");        Ok(())    }} #[derive(Accounts)]#[instruction(token_name: String)]pub struct CreateToken<'info> {    #[account(mut)]    pub signer: Signer<'info>,    #[account(        init,        payer = signer,        mint::decimals = 6,        mint::authority = signer.key(),        seeds = [b"token-2022-token", signer.key().as_ref(), token_name.as_bytes()],        bump,    )]    pub mint: InterfaceAccount<'info, Mint>,    pub system_program: Program<'info, System>,    pub token_program: Interface<'info, TokenInterface>,}

1. Line 49 token_interface::mint_to(cpi_context, amount)?;: Mints new tokens. The mint authority must sign.
2. Line 50 msg!("Mint Token");: Logs to the program log, which is visible in explorers and the test output.
3. Line 59 pub signer: Signer<'info>,: Requires this account to have signed the transaction.
4. Line 61 init,: Creates and pays for a new account. Space and payer must be specified.
5. Line 65 seeds = [b"token-2022-token", signer.key().as_ref(), token_name.as_bytes()],: Declares the PDA seeds. Anchor re-derives the address and rejects the account if it doesn't match.
6. Line 66 bump,: Uses the bump seed, the extra byte that pushes the derived address off the ed25519 curve.

     if account.player.energy < amount {        return err!(GameErrorCode::NotEnoughEnergy);    }     account.player.last_id = counter;    account.player.chop_tree(amount)?;    account.game_data.on_tree_chopped(amount)?;     msg!(        "You chopped a tree and got 1 wood. You have {} wood and {} energy left.",        ctx.accounts.player.wood,        ctx.accounts.player.energy    );     // We use a PDA as a mint authority for the metadata account because we want to be able to update the NFT from    // the program.    let seeds = b"nft_authority";    let bump = ctx.bumps.nft_authority;    let signer: &[&[&[u8]]] = &[&[seeds, &[bump]]];     // Update the metadata account with an additional metadata field in this case the player level    invoke_signed(        &anchor_spl::token_2022_extensions::spl_token_metadata_interface::instruction::update_field(

1. Line 15 return err!(GameErrorCode::NotEnoughEnergy);: An explicit validation that aborts the instruction with an error.
2. Line 22 msg!(: Logs to the program log, which is visible in explorers and the test output.
3. Line 30 let seeds = b"nft_authority";: Declares the PDA seeds. Anchor re-derives the address and rejects the account if it doesn't match.
4. Line 31 let bump = ctx.bumps.nft_authority;: Uses the bump seed, the extra byte that pushes the derived address off the ed25519 curve.
5. Line 35 invoke_signed(: Makes a CPI signed by a PDA. The signer seeds prove the program controls that address.
6. Line 36 &anchor_spl::token_2022_extensions::spl_token_metadata_interface::instruction::update_fiel: Targets the Token-2022 program instead of the original Token Program.