Rubyw, RuntimeError, capturing the stack, FXRuby

Ruby
1

Let’s say I’m running rubyw and a RunTimeError is raised …

and I’m using FXRuby (which is tangential to this question) …

and I want to put up a errorbox …

But I want to capture the error message that would normally go to
stdout, i.e. the call stack …

How would I capture the call stack to a string in a raised exception?

begin
raise RuntimeError, “Something bad happened”
rescue

What do I do here?

end

2

begin
puts 1/0
rescue Exception, NameError => e
print “this is an error [#{e}]”
print $!.inspect #Ruby places a reference to the associated Exception
object into the global variable $!
end

output: this is an error [divided by 0]#<ZeroDivisionError: divided by
0>

3

Joseph,

This does not give the call stack with file names and line numbers of
the exception.

Thanks.

Ralph

Wednesday, July 28, 2010, 2:58:20 PM, you wrote:

JES> begin
JES> puts 1/0
JES> rescue Exception, NameError => e
JES> print “this is an error [#{e}]”
JES> print $!.inspect Ruby places a reference to the associated
Exception
JES> object into the global variable $!
JES> end

JES> output: this is an error [divided by 0]#<ZeroDivisionError: divided
by 0>

From: Ralph S. [email protected]
Organization: Ralph S.
Reply-To: [email protected]
Date: Thu, 29 Jul 2010 05:44:36 +0900
To: ruby-talk ML [email protected]
Subject: rubyw, RuntimeError, capturing the stack, FXRuby

Let’s say I’m running rubyw and a RunTimeError is raised …

and I’m using FXRuby (which is tangential to this question) …

and I want to put up a errorbox …

But I want to capture the error message that would normally go to stdout, i.e.
the call stack …

How would I capture the call stack to a string in a raised exception?

4

Ralph S. wrote:

This does not give the call stack with file names and line numbers of
the exception.

Use Exception#backtrace:

irb(main):001:0> begin
irb(main):002:1* raise “Error”
irb(main):003:1> rescue => e
irb(main):004:1> puts e.backtrace
irb(main):005:1> end
(irb):2:in irb_binding' /opt/rubies/ruby-1.9.1-p429/lib/ruby/1.9.1/irb/workspace.rb:80:ineval’
/opt/rubies/ruby-1.9.1-p429/lib/ruby/1.9.1/irb/workspace.rb:80:in
evaluate' /opt/rubies/ruby-1.9.1-p429/lib/ruby/1.9.1/irb/context.rb:216:inevaluate’
/opt/rubies/ruby-1.9.1-p429/lib/ruby/1.9.1/irb.rb:157:in block (2 levels) in eval_input' /opt/rubies/ruby-1.9.1-p429/lib/ruby/1.9.1/irb.rb:271:insignal_status’
/opt/rubies/ruby-1.9.1-p429/lib/ruby/1.9.1/irb.rb:154:in block in eval_input' /opt/rubies/ruby-1.9.1-p429/lib/ruby/1.9.1/irb/ruby-lex.rb:244:inblock
(2 levels) in each_top_level_statement’
/opt/rubies/ruby-1.9.1-p429/lib/ruby/1.9.1/irb/ruby-lex.rb:230:in loop' /opt/rubies/ruby-1.9.1-p429/lib/ruby/1.9.1/irb/ruby-lex.rb:230:inblock
in each_top_level_statement’
/opt/rubies/ruby-1.9.1-p429/lib/ruby/1.9.1/irb/ruby-lex.rb:229:in
catch' /opt/rubies/ruby-1.9.1-p429/lib/ruby/1.9.1/irb/ruby-lex.rb:229:ineach_top_level_statement’
/opt/rubies/ruby-1.9.1-p429/lib/ruby/1.9.1/irb.rb:153:in eval_input' /opt/rubies/ruby-1.9.1-p429/lib/ruby/1.9.1/irb.rb:70:inblock in start’
/opt/rubies/ruby-1.9.1-p429/lib/ruby/1.9.1/irb.rb:69:in catch' /opt/rubies/ruby-1.9.1-p429/lib/ruby/1.9.1/irb.rb:69:instart’
/home/marvin/Programmieren/Programme/irb_/irb_.rb:37:in `’
=> nil
irb(main):006:0>

Vale,
Marvin

5

Sorry…

Des this help?

begin
puts 1/0
rescue Exception, NameError => e
print “this is an error [#{e}] ----->[#{e.backtrace}]<-------”
print $!.inspect #Ruby places a reference to the associated Exception
object into the global variable $!
end

this is an error [divided by 0]
----->[/Users/jes/error.rb:2:in `/’/Users/jes/error.rb:2]<-------
#<ZeroDivisionError: divided by 0>