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Files package

The Files package provides classes for working with files and directories.

Files are identified by FilePath objects, which represent both the path to the file and the capabilites for accessing the file at that path. FilePath objects can be used with the CreateFile and OpenFile primitives and the File class to get a reference to a file that can be used to write to and/or read from the file. It can also be used with the Directory object to get a reference to a directory object that can be used for directory operations.

The FileLines class allows a file to be accessed one line at a time.

The FileStream actor provides the ability to asynchronously write to a file.

The Path primitive can be used to do path-related operations on strings and characters.

Example program

This program opens the files that are given as command line arguments and prints their contents.

use "files"

actor Main
  new create(env: Env) =>
    for file_name in env.args.slice(1).values() do
      let path = FilePath(FileAuth(env.root), file_name)
      match OpenFile(path)
      | let file: File =>
        while file.errno() is FileOK do
        env.err.print("Error opening file '" + file_name + "'")

Public Types