Ruby调试

为什么80%的码农都做不了架构师？>>>   

转自：http://www.yiibai.com/ruby/ruby_debugger.html

一种语言多么容易使用，它通常包含了一些错误，如果它是多长了几行。为了帮助交易与错误，Ruby的标准分配包括一个调试.

为了启动Ruby调试器，加载调试库使用的命令行选项-r调试。调试器之前停止的可执行代码的第一行，并要求输入用户命令.

使用语法:

下面是使用Ruby调试器的使用语法:

$ ruby -r debug filename[, ...]

Ruby调试器命令:

下面是调试程序时，您可以使用完整的命令列表。这是没有必要使用完整的关键字给命令的一部分，在给[...]选项.

SN	Command with Description
1	b[reak] [< file| class>:]< line| method> Sets breakpoint to some position. Breakpoint is a place where you want to pause program execution for debugging purpose.
2	wat[ch] expression Sets watchpoints
3	cat[ch] (exception|off) Sets catchpoint to an exception.
4	b[reak] Displays breakpoints and watchpoints
5	del[ete] [n] Deletes breakpoints
6	disp[lay] expression Displays value of expression
7	undisp[lay] [ n] Removes display of n
8	c[ont] Continues execution
9	s[tep] [ n] Executes next n lines stepping into methods
10	n[ext] [ n] Executes next n lines stepping over methods
11	w[here] Displays stack frame
12	f[rame] Synonym for where
13	l[ist][<-| n- m>] Displays source lines from n to m
14	up [ n] Moves up n levels in the stack frame
15	down [ n] Moves down n levels in the stack frame
16	fin[ish] Finishes execution of the current method
17	tr[ace] [on|off] Toggles trace mode on and off
18	q[uit] Exits debugger
19	v[ar] g[lobal] Displays global variables
20	v[ar] l[ocal] Displays local variables
21	v[ar] i[instance] object Displays instance variables of object
22	v[ar] c[onst] object Displays constants of object
23	m[ethod] i[instance] object Displays instance methods of object
24	m[ethod] class| module Displays instance methods of the class or module
25	th[read] l[ist] Displays threads
26	th[read] c[ur[rent]] Displays current thread
27	th[read] n Stops specified thread
28	th[read] stop > Synonym for th[read] n
29	th[read] c[ur[rent]] n> Synonym for th[read] n
30	th[read] resume > Resumes thread n
31	p expression Evaluates the expression
32	h[elp] Displays help message
33	everything else Evaluates.

例子:

考虑下列文件hello.rb需要调试:

#!/usr/bin/env ruby
class Hello
   def initialize( hello )
      @hello  = hello
   end
   def hello
      @hello 
   end
end

salute = Hello.new( "Hello, Mac! - by www.yiibai.com" )
puts salute.hello

这里是一个交互式会话捕获。大胆写在给定的命令:

[root@ruby]# ruby -r debug hello.rb Debug.rb
Emacs support available.

hello.rb:3:class Hello
(rdb:1) v l salute => nil
(rdb:1) b 10 Set breakpoint 1 at hello.rb:10
(rdb:1) c Hello, Mac!
[root@ruby]#

转载于:https://my.oschina.net/ruby65/blog/72945