Ruby Debugging

Tracing

• Tracing will make the debugger print out each line of code as it is executed
• Easy way to run through loops and trace long running code
• Ctrl-c breaks the code at the line last traced to the screen

• 
  % ruby -rdebug test-rdb
  Debug.rb
  Emacs support available.
  
  test-rdb:4:class WordDictionary
  (rdb:1) n
  test-rdb:29:dictionary = WordDictionary.new
  (rdb:1) n
  test-rdb:30:p dictionary.findWord("shovel")
  (rdb:1) s
  test-rdb:19:    return if wordFragment.empty?
  (rdb:1) n
  test-rdb:20:    puts "dictionary size is #{@dict.size}"
  (rdb:1) n
  dictionary size is 235880
  test-rdb:21:    results = []
  (rdb:1) n
  test-rdb:22:    @sortedDictKeys.each do |key|
  (rdb:1) trace on
  Trace on.
  (rdb:1) c
  #0:test-rdb:22:Array:>:     @sortedDictKeys.each do |key|
  #0:test-rdb:23:WordDictionary:-:       results << key if key =~ /#{wordFragment}/
  #0:test-rdb:23:WordDictionary:-:       results << key if key =~ /#{wordFragment}/
  #0:test-rdb:23:WordDictionary:-:       results << key if key =~ /#{wordFragment}/
  #0:test-rdb:23:WordDictionary:-:       results << key if key =~ /#{wordFragment}/
  #0:test-rdb:23:WordDictionary:-:       results << key if key =~ /#{wordFragment}/
  <ctrl-c>
  (rdb:1) trace off
  Trace off.
  (rdb:1)