try_print and try_println

Non-panicking printing to stdout

This create provides an alternative print and println macro that don't panic.

The println and print macros provides a simple interface to output content on the stdout of a program. The macros panic when writing to stdout, and the failure condition could happen on external conditions.

Take the following rust code:

fn main() {
  for _ in 0..10000 {
    println!("line") {
  }
}

Piping the program output to other utilities could cause the program to panic, when the pipe is closed.

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thread '<main>' panicked at 'failed printing to stdout: Broken pipe (os error 32)', ../src/libstd/io/stdio.rs:588

Instead of panicking, it would be interesting to allow the developer to decide what to do with the error result, either ignoring it or panicking on it's own. This crate provides try_println and try_print as an alternative non-panicking macros.

The following code will not panic anymore when the pipe is closed.

#[macro_use] extern crate try_print;

fn main() {
  for _ in 0..10000 {
    if let Err(_) = try_println!("line") {
      std::process::exit(0);
    }
  }
}