Exception

class Exception < Object

Descendents of class Exception are used to communicate between raise methods and rescue statements in begin/end blocks. Exception objects carry information about the exception—its type (the exception's class name), an optional descriptive string, and optional traceback information.

Figure 22.1 not available

instance methods

backtrace

exc.backtrace → anArray

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

exception

exc.exception( [aString] ) → anException or exc

With no argument, returns the receiver. Otherwise, creates a new exception object of the same class as the receiver, but with a different message.

message

exc.message → aString

Returns the message associated with this exception.

set_backtrace

exc.set_backtrace( anArray ) → anArray

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

Extracted from the book "Programming Ruby - The Pragmatic Programmer's Guide"

Copyright © 2001 by Addison Wesley Longman, Inc. This material may be distributed only subject to the terms and conditions set forth in the Open Publication License, v1.0 or later (the latest version is presently available at http://www.opencontent.org/openpub/).

Distribution of substantively modified versions of this document is prohibited without the explicit permission of the copyright holder.

Distribution of the work or derivative of the work in any standard (paper) book form is prohibited unless prior permission is obtained from the copyright holder.

Programming Ruby

The Pragmatic Programmer's Guide

class Exception < Object

class methods

instance methods