std.io

APIs documented for this release.

use std.io;

API	Return value
std.io.read_stdin()	Result<String, IoError>; read until the end of input
std.io.write_stdout(text: String), std.io.write_stderr(text: String)	Result<Int, IoError>; bytes written
std.io.describe_error(error: IoError)	Human-readable error text

read_stdin waits for end of input and holds the entire input in memory. Write functions return bytes written. A complete pipeline example follows.

use std.io as io;
use std.string as text;

fn main() {
    let contents = match io.read_stdin() {
        Result.Ok(value) => value,
        Result.Err(error) => { panic(io.describe_error(error)); },
    };
    let words = text.split_ascii_whitespace(contents);
    for index in 0..words.len() {
        println(words.get(index));
    }
}

$ printf 'one two\nthree\n' | xen run stdin_words.xen
one
two
three

The IoError variants are InvalidPath, Open(Int), Read(Int), Write(Int), WriteZero, Close(Int), Metadata(Int), Directory(Int), Cwd(Int), and InvalidDirectoryEntry. Use describe_error for a message to display.