Purpose and Motivation

c = CollStream("5,7,hello,\"a comma, in quotes!\"");
r = CSVFileReader(c);

ERROR: Primitive '_FileOpen' failed.
Wrong type.

But... FileReader's interaction with the stream is, in total:

• stream.reset -- CollStream implements this
• stream.getChar -- CollStream implements this
• stream.close -- CollStream doesn't implement this, but we can use tryPerform to make it a no-op

So there is not a compelling reason why a FileReader must be accessing a file on disk and disallow a stream of characters in memory.

(Editorial: The usual OOP advice is to program toward interfaces rather than class hierarchies: respondsTo rather than isKindOf. This looks like a case where "oh, isKindOf will be fine just this once" except that it isn't, not really.)

Since the really relevant operation is getChar, this PR changes the FileReader constructor so that any object implementing getChar will be allowed as the stream.

Types of changes

• Bug fix

To-do list

• Code is tested
• All tests are passing
• Updated documentation -- Note that the entire FileReader hierarchy has spotty documentation. "Updated documentation" would require essentially a complete rewrite of four or five help files. I'm afraid at the moment I don't have time to do that. If someone is concerned about this, I would recommend opening an issue.
• This PR is ready for review