From: James Edward Gray II <james@...>
Date: 2006-06-05T01:42:32+09:00
Subject: Re: FasterCSV RCR?

On Jun 4, 2006, at 5:30 AM, NAKAMURA, Hiroshi wrote:

> James Edward Gray II wrote:
>> method arguments, we could get pretty close to perfect, but CSV does
>> some odd things like confuse open() with foreach() that I chose to  
>> avoid
>> in FasterCSV.  Because of that, I can't always be sure what to do  
>> when
>
> Can you please explain what are "odd"?

My biggest complaint with CSV is that open() behaves "oddly" and thus  
defeats all my normal expectations:

 >> File.open("example.csv", "w") do |csv|
?>   csv.puts "1,2,3"
 >>   csv.puts "a,b,c"
 >> end
=> nil
 >> require "csv"
=> true
 >> # typical Ruby style reading...
?> File.open("example.csv") do |file|
?>   file.each { |row| p row }
 >> end
"1,2,3\n"
"a,b,c\n"
=> #<File:example.csv (closed)>
 >> # or...
?> File.foreach("example.csv") do |row|
?>   p row
 >> end
"1,2,3\n"
"a,b,c\n"
=> nil
 >> # CSV's "odd" open() method...
 >> CSV.open("example.csv", "r") do |row|  # "r" required
?>   p row  # we get rows, not the file object
 >> end
["1", "2", "3"]
["a", "b", "c"]
=> nil

Of course, if you open in a writing mode, you do get a file like  
object.  It's inconsistent.

I'm confused about why CSV does this, since it offers the foreach()  
method, which normally fills this role.

Other CSV oddities (my opinion):

*  I always have to think, "Now do I want the *_line() method or the  
*_row() method here..."
*  Most methods take a field separator and a row separator, but  
foreach() and readlines() only take the row separator.
*  I have to set a field separator when I really just want to set a  
row separator.
*  A method called "generate_line()" doesn't involve a line ending.

>> 2.  We could drop compatibility and rename FasterCSV to CSV.  This  
>> way
>> people get all the good stuff where they expect it.  However, this  
>> would
>
> Can you please explain what are "good"?  I'll introduce those features
> into csv.rb.

Here's a selection of some features from my CHANGELOG that I am not  
aware of in CSV:

* Added built-in and custom data converters.  Built-in handle numbers  
and dates.
* Added auto-discovery for <tt>:row_sep</tt> (now the default).
* Added FasterCSV::filter() for easy Unix-like CSV filters.
* Added support for accessing fields by headers.
   * Headers can have their own converters.
   * Headers can be skipped or returned as needed.
   * FasterCSV::Row allows index or header access while retaining  
order and
     allowing for duplicate headers.
* <tt>:headers</tt> can now be set to an Array of headers to use.
* <tt>:headers</tt> can now be set to an external CSV String of  
headers to use.
* Provided support for the serialization of custom Ruby objects using  
CSV.
* Added FasterCSV::instance and FasterCSV()/FCSV() shortcuts for easy  
output.

James Edward Gray II