RegexpChallenge

Just recently I have been working with two different people to improve their regular expression skills. To help me in this endeavor, I built a trivial little script we have been using in IRb. To get started, you construct a new challenge object and add a couple of challenges:

>> reg_chal = RegexpChallenge.new
No challenges.
=> 
>> reg_chal.challenge("Gray, James", "James", "The names can vary.")
=> nil
>> reg_chal.challenge("abbbbbbbc bc", 10)
=> nil
>> reg_chal.challenge( "    \n\t  ", nil,
?>                     "We want to test for non-space data." )
=> nil
>> reg_chal.challenge( "cogs 9, widgets 12, ...", "12",
?>                     "The numbers can vary." )
=> nil
>> reg_chal.challenge( "I'm a simple sentence, with words.",
?>                     %w[I'm a simple sentence with words] )
=> nil

You can ask for challenges to see what you would like to solve:

>> reg_chal.challenges
Challenge #0:
   Input:  "Gray, James"
  Output:  "James"
    Note:  "The names can vary."
Challenge #1:
   Input:  "abbbbbbbc bc"
  Output:  10
Challenge #2:
   Input:  "    \n\t  "
  Output:  nil
    Note:  "We want to test for non-space data."
Challenge #3:
   Input:  "cogs 9, widgets 12, ..."
  Output:  "12"
    Note:  "The numbers can vary."
Challenge #4:
   Input:  "I'm a simple sentence, with words."
  Output:  ["I'm", "a", "simple", "sentence", "with", "words"]
=> nil

Finally, you attempt solutions by giving the system the index of the challenge, a method name to call on the input String, a Regexp to pass, and any other needed parameters:

>> reg_chal.solve(0, :=~, /, \w+/)
That is not a valid solution.
Expected output:  "James"
    Your output:  4
=> nil
>> reg_chal.solve(0, :[], /\w+$/)
Correct.  Nice job.
=> nil
>> reg_chal.solutions
Solution #0:
     Input:  "Gray, James"
    Output:  "James"
      Note:  "The names can vary."
  Solution:  [](/\w+$/)
=> nil

After you have played with it for a while you will probably build up some solutions and challenges. You can use the save() method to dump those to a YAML file and even load() them back later, if needed.

Finally, for some real fun, the challenger supports sharing the challenges over a network with another user. The host should just change the initial construction call to:

reg_chal = RegexpChallenge.host

And then another user can get a copy of the challenge object with:

reg_chal = RegexpChallenge.join("HOST IP ADDRESS HERE")

If that sounds like something you would like to play with, here's the actual code for the library you load into IRb.

Feel free to post challenges for people to try in the comments of this post.

.map { |line| line.sub(/^  /, "\\0\\0") }