impl iterators

This commit is contained in:
Samuele Iacoponi
2026-05-07 12:10:11 +02:00
parent bde0347c8f
commit ccb684bd6f
2 changed files with 88 additions and 11 deletions

View File

@@ -10,12 +10,12 @@ fn main() -> Result<(), Box<dyn Error>> {
// Args returns an iterator of args from cli
// Collect turns an iterator into a collection
// In this case transform values of args into a vector
let args: Vec<String> = env::args().collect();
// let args: Vec<String> = env::args().collect();
// let config = Config::build(&args)?;
// or
let config = Config::build(&args).unwrap_or_else(|err| {
let config = Config::build(env::args()).unwrap_or_else(|err| {
eprintln!("Problem parsing arguments: {err}");
process::exit(1);
});
@@ -56,15 +56,18 @@ struct Config {
}
impl Config {
fn build(args: &[String]) -> Result<Config, &'static str> {
if args.len() > 3 {
return Err("Too many arguments. Usage: minigrep <query> <file_path>");
}
if args.len() < 3 {
return Err("Too few arguments. Usage: minigrep <query> <file_path>");
}
let query = args[1].clone();
let file_path = args[2].clone();
fn build(mut args: impl Iterator<Item = String>) -> Result<Config, &'static str> {
args.next(); // skip first argument because is the name of the program
let query = match args.next() {
Some(arg) => arg,
None => return Err("No query strings")
};
let file_path = match args.next() {
Some(arg) => arg,
None => return Err("No file path")
};
let ignore_case = env::var("IGNORE_CASE").is_ok();

74
src/main_std.rs Normal file
View File

@@ -0,0 +1,74 @@
use std::fs;
use std::env;
use std::error::Error;
use std::process;
use minigrep::{search, search_case_insensitive};
fn main() -> Result<(), Box<dyn Error>> {
// Args returns an iterator of args from cli
// Collect turns an iterator into a collection
// In this case transform values of args into a vector
let args: Vec<String> = env::args().collect();
// let config = Config::build(&args)?;
// or
let config = Config::build(&args).unwrap_or_else(|err| {
eprintln!("Problem parsing arguments: {err}");
process::exit(1);
});
println!("Searching for {}", config.query);
println!("In file {}", config.file_path);
// run(config)?;
// or
if let Err(e) = run(config) {
eprintln!("Application error: {e}");
process::exit(1);
}
Ok(())
}
fn run (config: Config) -> Result<(), Box<dyn Error>> {
let contents: String = fs::read_to_string(config.file_path)?;
// results can't be used after contents die
let results = if config.ignore_case {
search_case_insensitive(&config.query, &contents)
} else {
search(&config.query, &contents)
};
println!("Found!");
for line in results { println!("{line}"); }
Ok(())
}
struct Config {
pub query: String,
pub file_path: String,
pub ignore_case: bool,
}
impl Config {
fn build(args: &[String]) -> Result<Config, &'static str> {
if args.len() > 3 {
return Err("Too many arguments. Usage: minigrep <query> <file_path>");
}
if args.len() < 3 {
return Err("Too few arguments. Usage: minigrep <query> <file_path>");
}
let query = args[1].clone();
let file_path = args[2].clone();
let ignore_case = env::var("IGNORE_CASE").is_ok();
Ok(Config { query, file_path, ignore_case })
}
}