Redirect STDOUT to function?

Hello,
I’m using Ruby as a scripting language for a program that supports the
WSH scripting interface, and I have a small problem: ‘puts’ and other
output functions don’t work (because STDOUT is invalid), as with ‘gets’
(but with STDIN). I’d like to redirect all accesses to STDOUT and STDIN
to my own functions, which would handle the IO through the main
application’s scripting interface.
I know that $stdout and others can be reassigned to other IO objects,
but I haven’t yet found a way to reliably redirect through a function
instead. Of course, this is probably because I’m relatively new to Ruby.
Does anyone know how I could do something like this?~Jonathan C.

On Mon, Sep 21, 2009 at 6:07 PM, Jonathan C. [email protected]
wrote:

I know that $stdout and others can be reassigned to other IO objects, but I haven’t yet found a way to reliably
redirect through a function instead. Of course, this is probably because I’m relatively new to Ruby.
Does anyone know how I could do something like this?~Jonathan C.

I haven’t tried this, but you should be able to create an IO-like
class/object where the methods you care about are (or call) the custom
functions you want to use. It would be nice if there was an module you
could mix into an object that implemented a few of the more basic
function which would build on those to provide the rest of the IO
interface, the way Enumerable builds on an “each” method in the class
its mixed into.

On the module suggestion, that would definitely be pretty great! Also,
I’ve already considered the IO-like class, and I’m just not sure where
to start. I don’t know what method(s) puts/p/gets/et cetera depend on,
or what the dependencies depend on; it’s a fairly difficult problem for
a newcomer to Ruby like me.

On Tue, 22 Sep 2009 10:07:16 +0900, Jonathan C. wrote:

could do something like this?~Jonathan C.
Create a brand new IO object that’s backed by the function you want.
(Maybe a thread and a StringIO would do the trick.)

–Ken

Hmm, what do you mean by “backed by the function you want”? My whole
problem is that I don’t know what function(s) to redefine in order for
the object to work reliably. For example, do all of the methods rely on
just one to access the data directly, or are there multiple such methods
I’d need to account for?

Why not just override the puts/gets function to your liking?

irb(main):001:0> def puts(str)
irb(main):002:1> :foo
irb(main):003:1> end
=> nil
irb(main):004:0> puts “Hello World”
=> :foo

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