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Ink! Timelock Contract - Ink Typing CST Test

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Ink! Timelock Contract — Ink Code

Funds can be withdrawn only after a specific block timestamp.

#[ink::contract]
mod timelock {
	#[ink(storage)]
	pub struct Timelock {
		unlock: u64,
	}

	impl Timelock {
		#[ink(constructor)]
		pub fn new(unlock: u64) -> Self { Self { unlock } }

		#[ink(message)]
		pub fn withdraw(&mut self) {
		assert!(self.env().block_timestamp() >= self.unlock);
		self.env().transfer(self.env().caller(), self.env().balance()).unwrap();
		}
	}
}

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.

Primary Use Cases

  • ▸High-security smart contracts
  • ▸DeFi protocols on Substrate
  • ▸NFT minting and marketplaces
  • ▸On-chain governance modules
  • ▸Wasm-based blockchain apps

Notable Features

  • ▸Rust-based syntax
  • ▸Compile-time type safety
  • ▸Wasm target for Substrate
  • ▸Macros for contract boilerplate
  • ▸Support for storage, events, and messages

Origin & Creator

Ink! was created by Parity Technologies, the team behind Substrate and Polkadot, to provide a safe Rust-based smart contract language for WebAssembly chains. Initial development started around 2018.

Industrial Note

Ink! is primarily used in Substrate-based chains and Polkadot parachains, for high-assurance contracts in DeFi, on-chain governance, NFT minting, and other blockchain-native applications.

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