On Wed, 18 Feb 2009, Mark J. Reed wrote:
On Wed, Feb 18, 2009 at 6:36 AM, Richard Hainsworth
<rich...@rusrating.ru> wrote:
What needs to be abstracted so that a perl6 program can know that a
Writeable may not be able to accept data (eg., because the file system is
full)?
I don't understand the question. To be a Writable, an object must
have a mechanism for accepting data. That mechanism may fail for any
of a large number of reasons (out of space, no permission, etc...),
but that's orthogonal to the fact that it's a Writable. A Readable is
not the same thing as "a Writable you can't actually write to right
now".
I've added an isWriteable to the IO::Writeable filehandle, which
should hopefully cover what Richard is after.
Side question: are HTTP URI's Writable? If so, I imagine that
translates into a PUT. Is there any benefit in abstracting out the
functionality of POST in a way that maps to other resource types?
Hmm. Interesting question. My reason for getting into S16 in the
first place was that I was interested in implementing some protocols. The
generic mechanisms that I think would be generally useful for protocols are:
- A grammar language, for the grammar of the protocol
- An event loop (see Perl 5 module "POE")
- A finite state machine (see POE again)
What I've been wondering about is how a grammar of the protocol would
interact with something that generates the protocol. I see the HTTP POST
command as an instance of the more general "Command with data"-type setup,
such as also occurs with SMTP's "data" command, although I think the two are
slightly different.
Anyway, I see the S16 method called "prompt" to be a step in the right
direction, although it doesn't seem to be attached to an appropriate
class/role yet, and also probably couldn't deal with the HTTP POST command.
These are just some random thoughts that occurred to me; maybe they'll
spark something in someone's mind.
:)
---------------------------------------------------------------------
| Name: Tim Nelson | Because the Creator is, |
| E-mail: wayl...@wayland.id.au | I am |
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