From: Stefano Crocco <stefano.crocco@...>
Date: 2010-10-23T22:48:00+09:00
Subject: Re: Non-Hard Coded File.open(newFile)

On Saturday 23 October 2010, Grant Curell wrote:
> |Like a lot of people I'm new to Ruby and I'm trying to do something I
> |thought would be pretty simple. I want the user to give me input in the
> |form of a filename and then subsequently open the file. Here is what I
> |have so far:
> |
> |class FileHandler
> |
> |  def initialize()
> |    @fileToParse = fileToParse #I get user input in the form of gets in
> |                               #another class.
> |    if File.new(fileToParse)
> |      puts 'File successfully opened.'
> |    else
> |      puts 'File failed to open.'
> |      Kernel.exit
> |
> |    end
> |  end
> |end
> |
> |However, that won't work. Doing something like
> |File.new("C:/Users/grant/Desktop/test.txt") works just fine though. The
> |way I'm currently doing it throws the following error:
> |
> |F:/Programming/eclipseWorkspace/CSE_655/file_handler.rb:8:in
> |`initialize': Invalid argument - C:/Users/grant/Desktop/test.txt
> |(Errno::EINVAL)

Your code seems mostly correct, but I don't exactly understand what 
fileToParse is. Is it a call to a fileToParse method (which in turn uses geets 
to retrieve the file name) or a variable? In the first case, I guess the if 
line should be

if File.new(@fileToParse) #note the @

Otherwise, the user will be asked to enter the file name twice.

If fileToParse is a variable, instead, where does it come from?


Also, it would be useful if you pointed out which is line 8 on your program. 
If I assume the first line is

class FileHandler

then line 8 is 'else', which I doubt could give you such an error.

Stefano