Helpers & modules

Modules

A Redstart project is a tree of modules, exactly like Rust. Declare a child module with mod, and refer across modules with ::.

// src/main.red
mod accounts;

handler on Token.Transfer(event) {
  let receiver = accounts::Account.loadOrCreate(event.params.to, { balance: BigInt.zero })
  // ...
}

// src/accounts.red
entity Account {
  id: Id<Bytes>
  balance: BigInt
}

Entities can live in one module and the handlers that write them in another; the compiler resolves and checks across all of them. mod name; resolves to a sibling name.red or a nested name/mod.red, with cycle detection.

Helper functions

Free fn declarations factor out shared logic. They lower to AssemblyScript functions, work across modules, and return typed values.

fn normalize(amount: BigInt, decimals: i32) -> BigDecimal {
  return amount.toBigDecimal() / exponent(decimals)
}

Entities touched inside a helper are dirty-tracked too: their saves are flushed at every return (and at the end of the calling handler), so the auto-save guarantee holds across function boundaries.