Attribute Macro smart_escrow 

#[smart_escrow]

Wraps a Smart Escrow finish function in the extern "C" fn finish() entry point the XRPL host calls when an EscrowFinish transaction invokes the feature.

The annotated function must:

• Take EscrowFinishContext as its first (and only) argument.
• Return FinishResult or i32.
• The attribute takes no arguments — #[smart_escrow(anything)] is a compile error.

Any other signature is a compile error pointing at the offending token.

Usage

Import this attribute from xrpl_escrow_stdlib, which re-exports it alongside EscrowFinishContext. Importing directly from xrpl_macros is unsupported because the generated code references types in xrpl_escrow_stdlib.

FinishResult and i32 convert into each other (From<i32> / From<FinishResult>), so a host error code can be propagated with .into() either way:

// Import from the feature crate, not from xrpl_macros directly.
use xrpl_escrow_stdlib::{smart_escrow, EscrowFinishContext, FinishResult};
use xrpl_escrow_stdlib::core::current_tx::traits::TransactionCommonFields;
use xrpl_escrow_stdlib::core::types::amount::Amount;

#[smart_escrow]
fn finish(ctx: EscrowFinishContext) -> FinishResult {
    let fee = match ctx.tx().get_fee() {
        Ok(f) => f,
        Err(e) => return e.code().into(), // i32 -> FinishResult
    };

    match fee {
        Amount::XRP { num_drops } if num_drops > 1000 => FinishResult::succeed(),
        _ => FinishResult::reject(),
    }
}

Returning i32 directly skips the macro’s FinishResult handling:

use xrpl_escrow_stdlib::{smart_escrow, EscrowFinishContext, FinishResult};
use xrpl_escrow_stdlib::core::current_tx::traits::TransactionCommonFields;
use xrpl_escrow_stdlib::core::types::amount::Amount;

#[smart_escrow]
fn finish(ctx: EscrowFinishContext) -> i32 {
    let fee = match ctx.tx().get_fee() {
        Ok(f) => f,
        Err(e) => return e.code(),
    };

    let result = match fee {
        Amount::XRP { num_drops } if num_drops > 1000 => FinishResult::succeed(),
        _ => FinishResult::reject(),
    };

    result.into()
}