typst/vendor/csv/examples/tutorial-perf-serde-01.rs
2024-10-16 14:18:46 +03:00

42 lines
840 B
Rust

#![allow(dead_code)]
use std::{error::Error, io, process};
use serde::Deserialize;
#[derive(Debug, Deserialize)]
#[serde(rename_all = "PascalCase")]
struct Record {
country: String,
city: String,
accent_city: String,
region: String,
population: Option<u64>,
latitude: f64,
longitude: f64,
}
fn run() -> Result<u64, Box<dyn Error>> {
let mut rdr = csv::Reader::from_reader(io::stdin());
let mut count = 0;
for result in rdr.deserialize() {
let record: Record = result?;
if record.country == "us" && record.region == "MA" {
count += 1;
}
}
Ok(count)
}
fn main() {
match run() {
Ok(count) => {
println!("{}", count);
}
Err(err) => {
println!("{}", err);
process::exit(1);
}
}
}