Hi all.
Assuming I have such C code:
VALUE proc; //contains object of class Proc
VALUE obj; //contains some object
How must look code, corresponding to obj.instance_eval(&proc) ?
Thanks.
V.
Hi, Victor.
rb_funcall(obj, rb_intern("instance_eval"), 1, proc);
_why
···
On Tue, Jun 06, 2006 at 02:16:31AM +0900, Victor Shepelev wrote:
Assuming I have such C code:
VALUE proc; //contains object of class Proc
VALUE obj; //contains some objectHow must look code, corresponding to obj.instance_eval(&proc) ?
I don't think that will work: proc is not a String but a Proc (TypeError).
See [ruby-talk:180647] and [ruby-talk:188958].
···
On Tue, Jun 06, 2006 at 04:12:14AM +0900, why the lucky stiff wrote:
On Tue, Jun 06, 2006 at 02:16:31AM +0900, Victor Shepelev wrote:
> Assuming I have such C code:
>
> VALUE proc; //contains object of class Proc
> VALUE obj; //contains some object
>
> How must look code, corresponding to obj.instance_eval(&proc) ?Hi, Victor.
rb_funcall(obj, rb_intern("instance_eval"), 1, proc);
--
Mauricio Fernandez - http://eigenclass.org - singular Ruby
Ohhhh. I guess define_method can take a proc, though. Back to ye olde cloaker.
Based on Guy's example:
wagon$ cat a.c
#include <ruby.h>
static VALUE
rb_proc_bind(VALUE obj, VALUE a)
{
VALUE meth, meta;
VALUE cloaker = ID2SYM(rb_intern("__cloaker__"));
meta = rb_singleton_class(obj);
rb_funcall(meta, rb_intern("define_method"), 2, cloaker, a);
meth = rb_funcall(meta, rb_intern("instance_method"), 1, cloaker);
rb_funcall(meta, rb_intern("remove_method"), 1, cloaker);
return rb_funcall(meth, rb_intern("bind"), 1, obj);
}
VALUE
obj_eval_it(int argc, VALUE *argv, VALUE self)
{
VALUE meth, proc;
rb_scan_args(argc, argv, "0&", &proc);
/* !^! here is your rb_instance_eval replacement, victor. !^! */
meth = rb_proc_bind(self, proc);
return rb_funcall(meth, rb_intern("call"), 0);
}
void Init_a()
{
VALUE obj = rb_funcall(rb_cObject, rb_intern("new"), 0);
rb_define_method(rb_cObject, "eval_it", obj_eval_it, -1);
rb_const_set(rb_cObject, rb_intern("OBJ"), obj);
}
wagon$ ruby -ra -e 'p Object::OBJ; Object::OBJ.eval_it { @b = 12 }; p Object::OBJ'
#<Object:0x80768dc>
#<Object:0x80768dc @b=12>
But now I really don't understand specific_eval().
_why
···
On Tue, Jun 06, 2006 at 04:43:10AM +0900, Mauricio Fernandez wrote:
On Tue, Jun 06, 2006 at 04:12:14AM +0900, why the lucky stiff wrote:
> rb_funcall(obj, rb_intern("instance_eval"), 1, proc);I don't think that will work: proc is not a String but a Proc (TypeError).
See [ruby-talk:180647] and [ruby-talk:188958].
> > rb_funcall(obj, rb_intern("instance_eval"), 1, proc);
>
> I don't think that will work: proc is not a String but a Proc
(TypeError).
>
> See [ruby-talk:180647] and [ruby-talk:188958].Ohhhh. I guess define_method can take a proc, though. Back to ye olde
cloaker.
Based on Guy's example:wagon$ cat a.c
#include <ruby.h>static VALUE
rb_proc_bind(VALUE obj, VALUE a)
{
VALUE meth, meta;
VALUE cloaker = ID2SYM(rb_intern("__cloaker__"));
meta = rb_singleton_class(obj);
rb_funcall(meta, rb_intern("define_method"), 2, cloaker, a);
meth = rb_funcall(meta, rb_intern("instance_method"), 1, cloaker);
rb_funcall(meta, rb_intern("remove_method"), 1, cloaker);
return rb_funcall(meth, rb_intern("bind"), 1, obj);
}VALUE
obj_eval_it(int argc, VALUE *argv, VALUE self)
{
VALUE meth, proc;
rb_scan_args(argc, argv, "0&", &proc);/* !^! here is your rb_instance_eval replacement, victor. !^! */
meth = rb_proc_bind(self, proc);
return rb_funcall(meth, rb_intern("call"), 0);
}void Init_a()
{
VALUE obj = rb_funcall(rb_cObject, rb_intern("new"), 0);
rb_define_method(rb_cObject, "eval_it", obj_eval_it, -1);
rb_const_set(rb_cObject, rb_intern("OBJ"), obj);
}wagon$ ruby -ra -e 'p Object::OBJ; Object::OBJ.eval_it { @b = 12 }; p
Object::OBJ'
#<Object:0x80768dc>
#<Object:0x80768dc @b=12>But now I really don't understand specific_eval().
Thanks why! Would try this.
Victor.
···
From: why the lucky stiff [mailto:ruby-talk@whytheluckystiff.net]
Sent: Monday, June 05, 2006 11:40 PM
On Tue, Jun 06, 2006 at 04:43:10AM +0900, Mauricio Fernandez wrote:
> On Tue, Jun 06, 2006 at 04:12:14AM +0900, why the lucky stiff wrote:
Nice hack 
Just for fun, here's another idea:
$ cat ieval.c
#include <ruby.h>
static VALUE instance_eval_proc;
static VALUE
do_instance_eval(VALUE obj, VALUE proc)
{
return rb_funcall(instance_eval_proc, rb_intern("call"), 2, obj, proc);
}
VALUE
obj_eval_it(int argc, VALUE *argv, VALUE self)
{
VALUE meth, proc;
rb_scan_args(argc, argv, "0&", &proc);
return do_instance_eval(self, proc);
}
void Init_ieval()
{
VALUE obj;
instance_eval_proc = rb_eval_string("lambda{|o,b| o.instance_eval(&b)}");
obj = rb_funcall(rb_cObject, rb_intern("new"), 0);
rb_define_method(rb_cObject, "eval_it", obj_eval_it, -1);
rb_const_set(rb_cObject, rb_intern("OBJ"), obj);
}
$ ruby -rieval -e 'p Object::OBJ; Object::OBJ.eval_it { @b = 12 }; p Object::OBJ'
#<Object:0xb7e13e14>
#<Object:0xb7e13e14 @b=12>
One can still hope matz's reflection ([180647] again) will bring a more
convenient way to do that, though 
···
On Tue, Jun 06, 2006 at 05:40:12AM +0900, why the lucky stiff wrote:
On Tue, Jun 06, 2006 at 04:43:10AM +0900, Mauricio Fernandez wrote:
> On Tue, Jun 06, 2006 at 04:12:14AM +0900, why the lucky stiff wrote:
> > rb_funcall(obj, rb_intern("instance_eval"), 1, proc);
>
> I don't think that will work: proc is not a String but a Proc (TypeError).
>Ohhhh. I guess define_method can take a proc, though. Back to ye olde cloaker.
Based on Guy's example:wagon$ cat a.c
#include <ruby.h>
static VALUE
rb_proc_bind(VALUE obj, VALUE a)
{
VALUE meth, meta;
VALUE cloaker = ID2SYM(rb_intern("__cloaker__"));
meta = rb_singleton_class(obj);
rb_funcall(meta, rb_intern("define_method"), 2, cloaker, a);
meth = rb_funcall(meta, rb_intern("instance_method"), 1, cloaker);
rb_funcall(meta, rb_intern("remove_method"), 1, cloaker);
return rb_funcall(meth, rb_intern("bind"), 1, obj);
}
--
Mauricio Fernandez - http://eigenclass.org - singular Ruby
Behalf Of Mauricio Fernandez
> > > rb_funcall(obj, rb_intern("instance_eval"), 1, proc);
> >
> > I don't think that will work: proc is not a String but a Proc
(TypeError).
> >
>
> Ohhhh. I guess define_method can take a proc, though. Back to ye olde
cloaker.
> Based on Guy's example:
>
> wagon$ cat a.c
> #include <ruby.h>
>
> static VALUE
> rb_proc_bind(VALUE obj, VALUE a)
> {
> VALUE meth, meta;
> VALUE cloaker = ID2SYM(rb_intern("__cloaker__"));
> meta = rb_singleton_class(obj);
> rb_funcall(meta, rb_intern("define_method"), 2, cloaker, a);
> meth = rb_funcall(meta, rb_intern("instance_method"), 1, cloaker);
> rb_funcall(meta, rb_intern("remove_method"), 1, cloaker);
> return rb_funcall(meth, rb_intern("bind"), 1, obj);
> }Nice hack
Just for fun, here's another idea:$ cat ieval.c
#include <ruby.h>
static VALUE instance_eval_proc;
static VALUE
do_instance_eval(VALUE obj, VALUE proc)
{
return rb_funcall(instance_eval_proc, rb_intern("call"), 2, obj,
proc);
}VALUE
obj_eval_it(int argc, VALUE *argv, VALUE self)
{
VALUE meth, proc;
rb_scan_args(argc, argv, "0&", &proc);return do_instance_eval(self, proc);
}void Init_ieval()
{
VALUE obj;instance_eval_proc = rb_eval_string("lambda{|o,b|
o.instance_eval(&b)}");
obj = rb_funcall(rb_cObject, rb_intern("new"), 0);
rb_define_method(rb_cObject, "eval_it", obj_eval_it, -1);
rb_const_set(rb_cObject, rb_intern("OBJ"), obj);
}$ ruby -rieval -e 'p Object::OBJ; Object::OBJ.eval_it { @b = 12 }; p
Object::OBJ'
#<Object:0xb7e13e14>
#<Object:0xb7e13e14 @b=12>
Thanks Mauricio! Something like this I've already invented Generally,
almost any feature we can't conveniently use from C, colud be used with
evaluating some string.
One can still hope matz's reflection ([180647] again) will bring a more
convenient way to do that, though
It would be the most straightforward way. When it would.
Matz?
V.
···
From: Mauricio Julio Fernandez Pradier [mailto:ferferse@telefonica.net] On
Sent: Wednesday, June 07, 2006 2:15 PM
On Tue, Jun 06, 2006 at 05:40:12AM +0900, why the lucky stiff wrote:
> On Tue, Jun 06, 2006 at 04:43:10AM +0900, Mauricio Fernandez wrote:
> > On Tue, Jun 06, 2006 at 04:12:14AM +0900, why the lucky stiff wrote: