Attribute Macro sewup_derive::ewasm_lib_fn

#[ewasm_lib_fn]

helps you to build your handler in other module

This macro will automatically generated as {FUNCTION_NAME}_SIG

// module.rs

use sewup::ewasm_api;

#[ewasm_lib_fn]
pub fn symbol(s: &str) {
    let symbol = s.to_string().into_bytes();
    ewasm_api::finish_data(&symbol);
}

// lib.rs

use module::{symbol, SYMBOL_SIG};

#[ewasm_main]
fn main() -> Result<()> {
    let contract = Contract::new()?;
    match contract.get_function_selector()? {
        SYMBOL_SIG => symbol("ETD"),
        _ => return Err(Error::UnknownHandle.into()),
    };
    Ok(())
}

There are two kind of inputs for ewasm_fn macro, first is functional signature, second and more are the fields of abijson. The functional signature can be specific as following ways. #[ewasm_lib_fn(00fdd58e)] or #[ewasm_lib_fn(“00fdd58e”)]

constant=true,
inputs=[
    { "internalType": "address", "name": "account", "type": "address" },
    { "internalType": "uint256", "name": "token_id", "type": "uint256" }
],
name=balanceOf,
outputs=[
    { "internalType": "uint256", "name": "", "type": "uint256" }
],
payable=false,
stateMutability=view
)]

The fields are not required, it can use default value if not provided. The default values of constant, payable are false; the default values of inputs and outputs are []; the default value of stateMutability is view; the default name is the camel case style of the function name.