Macro contract 

contract!() { /* proc-macro */ }

Generate a typed contract client from an ARC-4 ABI JSON file.

See algonaut_abi::contract for full documentation. contract!("path/to/contract.json"): generate a typed contract client from an ARC-4 ABI JSON file.

The macro reads the ABI JSON at compile time and generates a struct named after the contract (PascalCase) with methods for each ABI method. The path is resolved relative to CARGO_MANIFEST_DIR, matching include_str! behavior.

Example

algonaut::contract!("contracts/calculator.json");

// Use the generated struct
let client = Calculator::new(AppId(5), alice.address(), signer);
let call = client.add(2u64, 3u64).build(&params);

Generated Code

For a contract with methods add(uint64,uint64)uint64 and subtract(uint64,uint64)uint64:

pub struct Calculator {
    app_id: AppId,
    sender: Address,
    signer: Arc<dyn Signer>,
}

impl Calculator {
    pub fn new(app_id, sender, signer) -> Self { ... }
    pub fn add(&self, a: u64, b: u64) -> CalculatorAddBuilder { ... }
    pub fn subtract(&self, a: u64, b: u64) -> CalculatorSubtractBuilder { ... }
}

If the ABI JSON contains a networks field, named constructors are generated for known networks (testnet, mainnet, betanet).

Supported Types

The initial implementation supports scalar types with canonical Rust representations: uint8-uint512, bool, address, string, byte[]. Methods with transaction args, reference args, or compound types (arrays, tuples) generate a compile error with guidance to use the dynamic path.

Feature Requirements

The generated code uses MethodCall from the algonaut::atomic module, which requires the algod feature (included in default features). Ensure your algonaut dependency includes this feature.