Exception: Exception

Inherits:
Object show all
Defined in:
error.c

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#new(msg = nil) ⇒ Exception

Construct a new Exception object, optionally passing in

a message.




# File 'error.c'

/*
 * call-seq:
 *    Exception.new(msg = nil)   =>  exception
 *
 *  Construct a new Exception object, optionally passing in 
 *  a message.
 */

static VALUE
exc_initialize(argc, argv, exc)
    int argc;
    VALUE *argv;
    VALUE exc;
{
    VALUE arg;

    rb_scan_args(argc, argv, "01", &arg);
    rb_iv_set(exc, "mesg", arg);
    rb_iv_set(exc, "bt", Qnil);

    return exc;
}

Class Method Details

.exception(string) ⇒ Exception

With no argument, or if the argument is the same as the receiver, return the receiver. Otherwise, create a new exception object of the same class as the receiver, but with a message equal to string.to_str.

Returns:

Instance Method Details

#backtrace ⇒ Array

Returns any backtrace associated with the exception. The backtrace is an array of strings, each containing either "filename:lineNo: in 'method"' or "filename:lineNo."

def a
  raise "boom"
end

def b
  a()
end

begin
  b()
rescue => detail
  print detail.backtrace.join("\n")
end

produces:

prog.rb:2:in `a'
prog.rb:6:in `b'
prog.rb:10

Returns:




# File 'error.c'

/*
 *  call-seq:
 *     exception.backtrace    => array
 *  
 *  Returns any backtrace associated with the exception. The backtrace
 *  is an array of strings, each containing either ``filename:lineNo: in
 *  `method''' or ``filename:lineNo.''
 *     
 *     def a
 *       raise "boom"
 *     end
 *     
 *     def b
 *       a()
 *     end
 *     
 *     begin
 *       b()
 *     rescue => detail
 *       print detail.backtrace.join("\n")
 *     end
 *     
 *  <em>produces:</em>
 *     
 *     prog.rb:2:in `a'
 *     prog.rb:6:in `b'
 *     prog.rb:10
*/

static VALUE
exc_backtrace(exc)
    VALUE exc;
{
    static ID bt;

    if (!bt) bt = rb_intern("bt");
    return rb_attr_get(exc, bt);
}

#exception(string) ⇒ Exception

With no argument, or if the argument is the same as the receiver, return the receiver. Otherwise, create a new exception object of the same class as the receiver, but with a message equal to string.to_str.

Returns:




# File 'error.c'

/*
 *  Document-method: exception
 *
 *  call-seq:
 *     exc.exception(string) -> an_exception or exc
 *  
 *  With no argument, or if the argument is the same as the receiver,
 *  return the receiver. Otherwise, create a new
 *  exception object of the same class as the receiver, but with a
 *  message equal to <code>string.to_str</code>.
 *     
 */

static VALUE
exc_exception(argc, argv, self)
    int argc;
    VALUE *argv;
    VALUE self;
{
    VALUE exc;

    if (argc == 0) return self;
    if (argc == 1 && self == argv[0]) return self;
    exc = rb_obj_clone(self);
    exc_initialize(argc, argv, exc);

    return exc;
}

#inspect ⇒ String

Return this exception's class name an message

Returns:




# File 'error.c'

/*
 * call-seq:
 *   exception.inspect   => string
 *
 * Return this exception's class name an message
 */

static VALUE
exc_inspect(exc)
    VALUE exc;
{
    VALUE str, klass;

    klass = CLASS_OF(exc);
    exc = rb_obj_as_string(exc);
    if (RSTRING(exc)->len == 0) {
    return rb_str_dup(rb_class_name(klass));
    }

    str = rb_str_buf_new2("#<");
    klass = rb_class_name(klass);
    rb_str_buf_append(str, klass);
    rb_str_buf_cat(str, ": ", 2);
    rb_str_buf_append(str, exc);
    rb_str_buf_cat(str, ">", 1);

    return str;
}

#message ⇒ String #to_str ⇒ String

Returns the result of invoking exception.to_s. Normally this returns the exception's message or name. By supplying a to_str method, exceptions are agreeing to be used where Strings are expected.

Overloads:




# File 'error.c'

/*
 * call-seq:
 *   exception.message   =>  string
 *   exception.to_str    =>  string
 *
 * Returns the result of invoking <code>exception.to_s</code>.
 * Normally this returns the exception's message or name. By
 * supplying a to_str method, exceptions are agreeing to
 * be used where Strings are expected.
 */

static VALUE
exc_to_str(exc)
    VALUE exc;
{
    return rb_funcall(exc, rb_intern("to_s"), 0, 0);
}

#set_backtrace(array) ⇒ Array

Sets the backtrace information associated with exc. The argument must be an array of String objects in the format described in Exception#backtrace.

Returns:




# File 'error.c'

/*
 *  call-seq:
 *     exc.set_backtrace(array)   =>  array
 *  
 *  Sets the backtrace information associated with <i>exc</i>. The
 *  argument must be an array of <code>String</code> objects in the
 *  format described in <code>Exception#backtrace</code>.
 *     
 */

static VALUE
exc_set_backtrace(exc, bt)
    VALUE exc;
    VALUE bt;
{
    return rb_iv_set(exc, "bt", rb_check_backtrace(bt));
}

#to_s ⇒ String

Returns exception's message (or the name of the exception if no message is set).

Returns:




# File 'error.c'

/*
 * call-seq:
 *   exception.to_s   =>  string
 *
 * Returns exception's message (or the name of the exception if
 * no message is set).
 */

static VALUE
exc_to_s(exc)
    VALUE exc;
{
    VALUE mesg = rb_attr_get(exc, rb_intern("mesg"));

    if (NIL_P(mesg)) return rb_class_name(CLASS_OF(exc));
    if (OBJ_TAINTED(exc)) OBJ_TAINT(mesg);
    return mesg;
}

#message ⇒ String #to_str ⇒ String

Returns the result of invoking exception.to_s. Normally this returns the exception's message or name. By supplying a to_str method, exceptions are agreeing to be used where Strings are expected.

Overloads:




# File 'error.c'

/*
 * call-seq:
 *   exception.message   =>  string
 *   exception.to_str    =>  string
 *
 * Returns the result of invoking <code>exception.to_s</code>.
 * Normally this returns the exception's message or name. By
 * supplying a to_str method, exceptions are agreeing to
 * be used where Strings are expected.
 */

static VALUE
exc_to_str(exc)
    VALUE exc;
{
    return rb_funcall(exc, rb_intern("to_s"), 0, 0);
}