Ruby c extensions: How can I catch all exceptions, including things that aren't StandardErrors?

Question

In ruby,

begin
  # ...
rescue
  # ...
end

won't catch exceptions that aren't subclasses of StandardError. In C,

rb_rescue(x, Qnil, y, Qnil);

VALUE x(void) { /* ... */ return Qnil; }
VALUE y(void) { /* ... */ return Qnil; }

will do the same thing. How can I rescue Exception => e from a ruby C extension (instead of just rescue => e)?

score 5 · Accepted Answer · answered Jul 09 '10 at 22:23

5

Ruby needs more documentation. I had to go into the ruby source code, and this is what I found:

VALUE
rb_rescue(VALUE (* b_proc)(ANYARGS), VALUE data1,
      VALUE (* r_proc)(ANYARGS), VALUE data2)
{
    return rb_rescue2(b_proc, data1, r_proc, data2, rb_eStandardError,
              (VALUE)0);
}

So, the answer to my question (i guess) would be:

rb_rescue2(x, Qnil, y, Qnil, rb_eException, (VALUE)0);

VALUE x(void) { /* ... */ return Qnil; }
VALUE y(void) { /* ... */ return Qnil; }

answered Jul 09 '10 at 22:23

Adrian

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+1 Just hit the same problem and this discovery resolved my problem. – Frerich Raabe Jun 23 '11 at 11:09
I would vote this up, but am not clear on what callbacks do what. What gets called in the event of a rescue? What is being rescued? – Translunar Aug 09 '13 at 02:43
I would assume `b_proc` is the code after the `begin` statement, and `r_proc` is the rescue code. – Vortico Oct 22 '13 at 12:40

Ruby c extensions: How can I catch all exceptions, including things that aren't StandardErrors?

1 Answers1