HashWalker

Walk a hash like a hash walker would.

A ruby DSL for walking through hashes. Its the reverse of XmlBuilder or jbuilder. Works with symbol or string keys.

Usage

given this hash:

    hash = {
      :host => 'ruby-lang.org',
      :protocol => 'http://',
      :headers => {:user_agent => 'safari'},
      :cache => {'strategy' => {'type' => 'lazy'}}
    }

you would traverse it with the following ruby DSL:

    HashWalker.walk(hash) do
      cache do
        strategy do
          puts type
        end
      end
    end

Arrays

given this hash:

    hash = { stories: [
        {:title => 'a', :url => 'http://some-url/a'},
        {:title => 'b', :url => 'http://some-url/b'},
        {:title => 'c', :url => 'http://some-url/c'}
    ]}

you would traverse it with the following ruby DSL:

    HashWalker.walk(hash) do
      stories do
        puts title
        puts url
      end
    end

Non existant keys

Non existant keys are skipped gracefully

    hash = { :set1 => { :a => 1, :b => 1 }}

you would traverse it with the following ruby DSL:

    HashWalker.walk(hash) do
      set1 do
        puts a
      end

      set2 do
        puts a
      end
    end

you would get this output:

  1

Contributing

Clone and send a pull request, preferably with a test. Run the tests using rake

• TODO: map vs. join? at least test it
• TODO: ability to reach out to parent (parent. something?)
• TODO: ability to reach out to siblings?
• TODO: Top level arrays/ (are they valid JSON and valid HAshes?)
• TODO: accept JSON or HASH or HTTParty response
• TODO: HTTParty adapter. httparty_response.walk()
• TODO: Adapter for other libaries? VCR? Mechanize? REGEXP? Nokogiri?
• TODO: return a value from the entire outer bloc
• TODO: test more stuff at the top level / outer block level.
• TODO: top level array? (then its not a hash)
• TODO: support for objects and enumerables along with Hash's and Arrays
• TODO: access to key names
• TODO: generate the DSL based on an existing hash (like a VCR cassette?)
• TODO: don't look for Hash's and Array's, look for objects that act like Hash's and act like Arrays. (objects and enumarbles?)
• TODO: Create an operator? (possibly using superators?) For example, a tilde unary operator is possible:

so instead of

   HashWalker::Walk(my_hash) do
     stories do
       puts title
     end
   end

we could do

   ~my_hash do
     stories do
       puts title
     end
   end

or

we could do

   my_hash ~~~ do
     stories do
       puts title
     end
   end