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Module 0x2::iota

Coin<IOTA> is the token used to pay for gas in IOTA. It has 9 decimals, and the smallest unit (10^-9) is called "nano".

use 0x1::option;
use 0x2::balance;
use 0x2::coin;
use 0x2::transfer;
use 0x2::tx_context;
use 0x2::url;

Struct IOTA​

Name of the coin

struct IOTA has drop
Fields
dummy_field: bool

Struct IotaTreasuryCap​

The IOTA token treasury capability. Protects the token from unauthorized changes.

struct IotaTreasuryCap has store
Fields

Constants​

Sender is not @0x0 the system address.

const ENotSystemAddress: u64 = 1;
const EAlreadyMinted: u64 = 0;

Function new​

Register the IOTA Coin to acquire IotaTreasuryCap. This should be called only once during genesis creation.

fun new(ctx: &mut tx_context::TxContext): iota::IotaTreasuryCap
Implementation
fun new(ctx: &mut TxContext): IotaTreasuryCap {
assert!(ctx.sender() == @0x0, ENotSystemAddress);
assert!(ctx.epoch() == 0, EAlreadyMinted);
let (treasury, metadata) = coin::create_currency(
IOTA {},
9,
b"IOTA",
b"IOTA",
b"The main (gas)token of the IOTA Network.",
option::some(url::new_unsafe_from_bytes(b"https://iota.org/logo.png")),
ctx
);
transfer::public_freeze_object(metadata);
IotaTreasuryCap {
inner: treasury,
}
}

Function transfer​

public entry fun transfer(c: coin::Coin<iota::IOTA>, recipient: address)
Implementation
public entry fun transfer(c: coin::Coin<IOTA>, recipient: address) {
transfer::public_transfer(c, recipient)
}

Function mint​

Create an IOTA coin worth value and increase the total supply in cap accordingly.

public fun mint(cap: &mut iota::IotaTreasuryCap, value: u64, ctx: &mut tx_context::TxContext): coin::Coin<iota::IOTA>
Implementation
public fun mint(cap: &mut IotaTreasuryCap, value: u64, ctx: &mut TxContext): Coin<IOTA> {
assert!(ctx.sender() == @0x0, ENotSystemAddress);
cap.inner.mint(value, ctx)
}

Function mint_balance​

Mint some amount of IOTA as a Balance and increase the total supply in cap accordingly. Aborts if value + cap.inner.total_supply >= U64_MAX

public fun mint_balance(cap: &mut iota::IotaTreasuryCap, value: u64, ctx: &tx_context::TxContext): balance::Balance<iota::IOTA>
Implementation
public fun mint_balance(cap: &mut IotaTreasuryCap, value: u64, ctx: &TxContext): Balance<IOTA> {
assert!(ctx.sender() == @0x0, ENotSystemAddress);
cap.inner.mint_balance(value)
}

Function burn​

Destroy the IOTA coin c and decrease the total supply in cap accordingly.

public fun burn(cap: &mut iota::IotaTreasuryCap, c: coin::Coin<iota::IOTA>, ctx: &tx_context::TxContext): u64
Implementation
public fun burn(cap: &mut IotaTreasuryCap, c: Coin<IOTA>, ctx: &TxContext): u64 {
assert!(ctx.sender() == @0x0, ENotSystemAddress);
cap.inner.burn(c)
}

Function burn_balance​

Destroy the IOTA balance b and decrease the total supply in cap accordingly.

public fun burn_balance(cap: &mut iota::IotaTreasuryCap, b: balance::Balance<iota::IOTA>, ctx: &tx_context::TxContext): u64
Implementation
public fun burn_balance(cap: &mut IotaTreasuryCap, b: Balance<IOTA>, ctx: &TxContext): u64 {
assert!(ctx.sender() == @0x0, ENotSystemAddress);
cap.inner.supply_mut().decrease_supply(b)
}

Function total_supply​

Return the total number of IOTA's in circulation.

public fun total_supply(cap: &iota::IotaTreasuryCap): u64
Implementation
public fun total_supply(cap: &IotaTreasuryCap): u64 {
cap.inner.total_supply()
}