Introduction

Archetype is an elegant generic-purpose language to develop smart contracts on the Tezos blockchain. It's a DSL (domain-specific language ) for Tezos that facilitates formal verification and transcodes contracts to SmartPy and LIGO.

It supports all Michelson features but also provides exclusive high-level features for a precise and concise source code, that make contracts easier to develop, read and maintain.

Looking at a simple Archetype contract

Create a file hello.arl

archetype hello

variable msg : string = "Hello"

entry input(name : string) {
  msg += (length(msg) > 5 ? "," : "") + " " + name
}

The contract starts with the archetype keyword followed by a contract identifier.

For example:

archetype escrow

/* ... */

Parameters

A contract may have parameters. A parameter value is not in the source code and is provided at deployment (origination) time. For example, the address of the contract owner is typically a contract parameter.

By default, a contract parameter is an element of the contract storage. It is defined by an identifier and a type. The list of parameters follows the contract's identifier between parenthesis and the parameters are separated by commas.

For example:

archetype escrow(seller : address, buyer : address)

/* ... */

The seller and buyer addresses then need to be set at deployment time.

Deploy a contract with Completium:

The Completium CLI is the command line utility to install Archetype compiler and manage contracts (deploy, call).

To install and initialize Completium do:

$ npm install -g @completium/completium-cli
$ completium-cli init

Then you can deploy the contract with

completium-cli deploy hello.arl

Call contract's entrypoint input with argument "Archetype":

completium-cli call hello --entry input --arg '{ "name": "Archetype" }'

Further reading:

• Medium article
• How To Verify a smart contract with Archetype