This crate provides a streaming CSV (comma separated values) writer and
reader that works with the serialize
crate to do type based encoding
and decoding. There are two primary goals of this project:
- The default mode of parsing should just work. This means the parser will bias toward providing a parse over a correct parse (with respect to RFC 4180).
- Convenient to use by default, but when performance is needed, the API will provide an escape hatch.
Licensed under the UNLICENSE.
The API is fully documented with lots of examples: https://burntsushi.net/rustdoc/csv/.
Here is a full working Rust program that decodes records from a CSV file. Each record consists of two strings and an integer (the edit distance between the strings):
extern crate csv;
use std::path::Path;
fn main() {
let fp = &Path::new("./data/simple.csv");
let mut rdr = csv::Reader::from_file(fp);
for record in rdr.decode() {
let (s1, s2, dist): (String, String, usize) = record.unwrap();
println!("({}, {}): {}", s1, s2, dist);
}
}
Don't like tuples? That's fine. Use a struct instead:
extern crate csv;
extern crate "rustc-serialize" as rustc_serialize;
use std::path::Path;
#[derive(RustcDecodable)]
struct Record {
s1: String,
s2: String,
dist: u32,
}
fn main() {
let fp = &Path::new("./data/simple.csv");
let mut rdr = csv::Reader::from_file(fp);
for record in rdr.decode() {
let record: Record = record.unwrap();
println!("({}, {}): {}", record.s1, record.s2, record.dist);
}
}
Do some records not have a distance for some reason? Use an Option
type!
#[derive(RustcDecodable)]
struct Record {
s1: String,
s2: String,
dist: Option<u32>,
}
You can also read CSV headers, change the delimiter, use enum
types or just
get plain access to records as vectors of strings. There are examples with more
details in the documentation.
This crate works with Cargo and is on
crates.io. The package is regularly updated.
Add is to your Cargo.toml
like so:
[dependencies]
csv = "*"
# other deps...
There are some rough benchmarks (compared with Go) here: https://github.com/BurntSushi/rust-csv/tree/master/bench