Implement redirection operators for file- and byte-iterators

[holgerbrandl]

The following examples from the README.md are not working

Seq(file1, file2) >: file3   
Seq(file1, file2) >>: file3
cat(file1) >>: file

This is because both operators just allow for String as input and not for Iterable[File] or Seq[Iterator[Byte]].

There's also a typo in the first example >: should be BACKTICK>:BACKTICK

Also the File.append* API does not allow for an efficient concatenation of Files. To do so we need to write something like:

val chunkResults: Iterable[File] = ...

chunkResults.map(_.contentAsString).foreach(combinedFile.appendLines(_))
// or
chunkResults.map(_.bytes.toArray).foreach(combinedBlastOut.append)

Both approaches load the complete input files into memory and don't stream/iterate through them which will cause problems for larger files.

Suggestion:

/**
 * Overwrite destination with this file's contents
 *
 * @param destination
 * @return destination
 */
def >(destination: File): File = ???

/**
 * Append this file's contents to destination
 *
 * @param destination
 * @return destination
 */
def `>>`(destination: File): File = ???

[mpollmeier]

Any updates on when this this will be fixed?
Concatenating files and writing them to a new file is the most basic thing a file library should do IMO. Is there a workaround? I used unix4j in the end.

[pathikrit]

This issue is only for the operators DSL. You can append by calling append just fine.