Appending text

append_text(path, text) adds exact UTF-8 bytes to the end of a file, creating it if necessary. It returns the number of characters appended. Errors can leave partial output; concurrent appends are not guaranteed to be atomic records.

Run this in a scratch directory: it replaces plenty-log.txt before appending.

def log_example() -> Result[str, IoError]:
    write_text("plenty-log.txt", "started\n")?
    append_text("plenty-log.txt", "finished\n")?
    read_text("plenty-log.txt")

def main() -> Result[(), AllocError | IoError]:
    print(str.repr(log_example())?)?
    Ok(())

Result[str, IoError].Ok("started\nfinished\n")