Logging

#![no_std]
use soroban_sdk::{contract, contractimpl, Env, String, log};
 
#[contract]
pub struct LoggingExample;
 
#[contractimpl]
impl LoggingExample {
    /// This is an implementation of logging in Soroban.
 
    pub fn output(env: Env, info: String) {
        log!(&env, "Message: {}!", info);
    }
}

Guide

#![no_std] This attribute prevents linking to the standard library, making the code lighter and more efficient for Soroban contracts. It's big so we save on size.

use soroban_sdk::{contract, contractimpl, Env, log} Imports stuffs from the Soroban SDK. Env is basic Soroban type, we need it because we can't use the Rust standard library.

#[contract] Marks the struct as a Soroban smart contract. Soroban smart contracts are defined as Rust structs.

#[contractimpl] Marks the implementation block as containing contract methods and transforms it to code that Soroban can evaluate directly

pub Marks a function as external, meaning it can be invoked outside of the context of the contract code it self.

Explanation

Simply logs the input string passed into the contract's core function.

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