Consider these two short programs:
ARGF.read
and
require 'yaml'
YAML.load(ARGF)
Then call them like so:
$ ruby foo.rb foo
The first program prints the contents of foo and exits. The second program waits for ^D from the terminal, and then tries to parse the YAML and go on with life.
I want ARGF to behave like it does in the first example, in the second example. Of course I could do YAML.load(ARGF.read) but that doesn't satisfy my curiousity. 
IMO, YAML.load *should* do this with ARGF because the following works:
f = File.open("foo", "rb")
YAML.load(f)
f.close
-austin
On Thu, 5 Aug 2004 02:36:29 +0900, Hans Fugal <hans@fugal.net> wrote:
Consider these two short programs:
ARGF.read
and
require 'yaml'
YAML.load(ARGF)Then call them like so:
$ ruby foo.rb foo
The first program prints the contents of foo and exits. The second
program waits for ^D from the terminal, and then tries to parse the YAML
and go on with life.I want ARGF to behave like it does in the first example, in the second
example. Of course I could do YAML.load(ARGF.read) but that doesn't
satisfy my curiousity.
--
Austin Ziegler * halostatue@gmail.com
* Alternate: austin@halostatue.ca
Hans Fugal wrote:
require 'yaml'
YAML.load(ARGF)... waits for ^D from the terminal, and then tries to parse the YAML and go on with life.
Try:
require 'yaml'
until ARGF.closed?
YAML::load( ARGF.file )
ARGF.close
end
Like Robert said, ARGF isn't an IO object. If you run ARGF.to_io, you'll only get the first stream. ARGF is a set of streams. The question is: does each supplied stream separately contain a YAML document? Or do the streams represent chunks of a partitioned YAML document? Your example seems to indicate the second. But I would have found the first more natural.
#1. YAML::load( ARGF.read )
#2. ARGF.collect { |doc| YAML::load( doc ) }
Which is desired?
_why
"Austin Ziegler" <halostatue@gmail.com> schrieb im Newsbeitrag
news:9e7db91104080410463cea4c22@mail.gmail.com...
> Consider these two short programs:
> ARGF.read
> and
> require 'yaml'
> YAML.load(ARGF)
>
> Then call them like so:
>
> $ ruby foo.rb foo
>
> The first program prints the contents of foo and exits. The second
> program waits for ^D from the terminal, and then tries to parse the YAML
> and go on with life.
>
> I want ARGF to behave like it does in the first example, in the second
> example. Of course I could do YAML.load(ARGF.read) but that doesn't
> satisfy my curiousity.IMO, YAML.load *should* do this with ARGF because the following works:
f = File.open("foo", "rb")
YAML.load(f)
f.close
Not so fast: ARGF is quite special. It's especially *no* an IO. It just
happens to implement some methods of IO. IMHO it's not reasonable to invoke
YAML.load(ARGF) because ARGF might draw its data from any number of files -
including stdin. IMHO it's not very practical to distribute YAML data
across multiple files. The case is differnt for grep like tools that can
reasonable operate on a multitude of files.
Just my 0.02EUR...
Kind regards
robert
On Thu, 5 Aug 2004 02:36:29 +0900, Hans Fugal <hans@fugal.net> wrote:
why the lucky stiff wrote:
Like Robert said, ARGF isn't an IO object. If you run ARGF.to_io, you'll only get the first stream. ARGF is a set of streams. The question is: does each supplied stream separately contain a YAML document? Or do the streams represent chunks of a partitioned YAML document? Your example seems to indicate the second. But I would have found the first more natural.
#1. YAML::load( ARGF.read )
#2. ARGF.collect { |doc| YAML::load( doc ) }
In my case, #1, or perhaps YAML::load(ARGF.file) - I haven't decided yet. This satisfies my curiosity, thank you very much!
I agree it doesn't always make sense, maybe not even often, but sometimes it does. There's nothing that says a yaml document has to reside in one file, and there's certainly good reason to take it in on stdin.
Robert Klemme wrote:
"Austin Ziegler" <halostatue@gmail.com> schrieb im Newsbeitrag
news:9e7db91104080410463cea4c22@mail.gmail.com...On Thu, 5 Aug 2004 02:36:29 +0900, Hans Fugal <hans@fugal.net> wrote:
Consider these two short programs:
ARGF.read
and
require 'yaml'
YAML.load(ARGF)Then call them like so:
$ ruby foo.rb foo
The first program prints the contents of foo and exits. The second
program waits for ^D from the terminal, and then tries to parse the YAML
and go on with life.I want ARGF to behave like it does in the first example, in the second
example. Of course I could do YAML.load(ARGF.read) but that doesn't
satisfy my curiousity.IMO, YAML.load *should* do this with ARGF because the following works:
f = File.open("foo", "rb")
YAML.load(f)
f.closeNot so fast: ARGF is quite special. It's especially *no* an IO. It just
happens to implement some methods of IO. IMHO it's not reasonable to invoke
YAML.load(ARGF) because ARGF might draw its data from any number of files -
including stdin. IMHO it's not very practical to distribute YAML data
across multiple files. The case is differnt for grep like tools that can
reasonable operate on a multitude of files.Just my 0.02EUR...
Kind regards
robert
