Compile Example with Cargo | Generated by AI

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To get your example compiling, you need to:

  1. Declare the crates you’re using in Cargo.toml
  2. Provide a main function (and a runtime, if you’re using async requests)
  3. Remove the now‐unnecessary edition2024 feature flag

1. Update Cargo.toml

[package]
name = "example"
version = "0.1.0"
edition = "2024"        # pick the current edition; no need for a feature flag

[dependencies]
# Async runtime for `#[tokio::main]`
tokio = { version = "1.28", features = ["macros", "rt-multi-thread"] }

# HTTP client with JSON support
reqwest = { version = "0.11", features = ["json"] }

# Serde for (de)serialization
serde = { version = "1.0", features = ["derive"] }
serde_json = "1.0"

Note: Remove any [features] section that lists edition2024 — it’s built in as of Cargo 1.85.

2. Provide an async main

If you want to use reqwest::Client (async), wrap your code in Tokio’s runtime:

// src/main.rs
use reqwest::{Client, StatusCode};
use serde_json::{json, Value};

#[tokio::main]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
    // Build a client
    let client = Client::new();

    // Example GET
    let res = client
        .get("https://httpbin.org/status/200")
        .send()
        .await?;

    println!("Status: {}", res.status());

    // Example JSON body
    let body: Value = res.json().await?;
    println!("JSON response: {}", body);

    Ok(())
}

3. (Alternative) Use blocking reqwest

If you don’t want async or Tokio, switch to reqwest::blocking and drop the tokio dependency:

// In Cargo.toml, remove tokio and change reqwest to:
reqwest = { version = "0.11", features = ["blocking", "json"] }

// src/main.rs:
use reqwest::blocking::Client;
use serde_json::Value;

fn main() -> Result<(), Box<dyn std::error::Error>> {
    let client = Client::new();
    let res = client.get("https://httpbin.org/status/200").send()?;
    println!("Status: {}", res.status());
    let body: Value = res.json()?;
    println!("JSON response: {}", body);
    Ok(())
}

With those changes, running cargo build (and then cargo run) should succeed.

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