Feature #5129: Create a core class "FileArray" and make "ARGF" its instance

• Status: Assigned
• Assignee: matz (Yukihiro Matsumoto)
• Target version: -

[yimutang (Joey Zhou)]

I suggest to create a class "FileArray" whose instance behaves just like ARGF do.
And I think ARGF should be an instance of FileArray. Now when I "p ARGF.class", I get "ARGF.class", so ARGF is an instance of ARGF.class, how meaningless it is.

FileArray methods:

# create an instance
fa = FileArray.new('a.txt','b.txt','c.txt')

# take many methods from IO
# most methods from ARGF should be instance methods of ARGF 
fa.each {|line| puts line }
fa.realines
fa.filename # current file

# but "argv" not
p fa.file_list # in ARGF, its ARGF.argv, but #argv is not a proper name for FileArray

# ARGV array can be modified, adding new file into it, all replace to a new file list.
# FileArray should add some methods to modify the inner file list.
fa.insert(3,"d.txt")
fa.delete('a.txt')

With FileArray, You can create multiple ARGF-like file arrays simultaneously.

For example, I want to mix two groups of files, not two files:

a_files = FileArray.new(*Dir.glob('a*.txt'))
b_files = FileArray.new(*Dir.glob('b*.txt'))

enum_a = a_files.each
enum_b = b_files.each

loop do
 puts enum_a.next
 puts enum_b.next
end

[mame (Yusuke Endoh)]

• Status changed from Open to Assigned
• Assignee set to matz (Yukihiro Matsumoto)

Hello,

I like the idea, but it requires matz's approval.

Now when I "p ARGF.class", I get "ARGF.class", so ARGF is an instance of ARGF.class, how meaningless it is.

FYI: In fact, it is meaningful. You can "exploit" it.

$ cat a.txt
foo
$ cat b.txt
bar
$ ruby -e 'p ARGF.class.new("a.txt", "b.txt").read'
"foo\nbar\n"

I'm not sure if this behavior is the spec, though.

--
Yusuke Endoh [e-mail]

[mame (Yusuke Endoh)]

• Target version set to 2.6

[naruse (Yui NARUSE)]

• Target version deleted (2.6)

[shevegen (Robert A. Heiler)]

Just noticed it for the upcoming developer meeting. I agree with the
functionality; not sure if FileArray is a good name, but I also can
not suggest a better name. (The functionality is fine in my opinion)

[nobu (Nobuyoshi Nakada)]

• Description updated (diff)

yimutang (Joey Zhou) wrote:

For example, I want to mix two groups of files, not two files:

FileGroup ?