Ink! Simple ERC20 Token - Ink Typing CST Test

Ink! Simple ERC20 Token — Ink Code

A basic ERC20-like token implementation in Ink! supporting mint, transfer, and balance queries.

#[ink::contract]
mod token {
	#[ink(storage)]
	pub struct Token {
		total: u64,
		balances: ink::storage::Mapping<AccountId, u64>,
	}

	impl Token {
		#[ink(constructor)]
		pub fn new(amount: u64) -> Self {
		let caller = Self::env().caller();
		let mut balances = ink::storage::Mapping::new();
		balances.insert(caller, &amount);
		Self { total: amount, balances }
		}

		#[ink(message)]
		pub fn transfer(&mut self, to: AccountId, amount: u64) {
		let caller = self.env().caller();
		let caller_balance = self.balances.get(caller).unwrap_or(0);
		assert!(caller_balance >= amount);
		self.balances.insert(caller, &(caller_balance - amount));
		let to_balance = self.balances.get(to).unwrap_or(0);
		self.balances.insert(to, &(to_balance + amount));
		}
	}
}

Ink Language Guide

Ink! is a Rust-based eDSL (embedded domain-specific language) for writing smart contracts on the Substrate blockchain framework. It emphasizes safety, efficiency, and tight integration with Polkadot and Substrate ecosystems.

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