yaml ?nodes? or nested maps

rubyonrails-talk
1

I want to iterate ?nodes? and ?leafs? for a yaml document:

thufir@ARRAKIS:~/projects/rss$ thufir@ARRAKIS:~/projects/rss$ ruby user.rb user.rb:6: undefined method `' for nil:NilClass (NoMethodError)   from user.rb:5:in `each_key'   from user.rb:5 thufir@ARRAKIS:~/projects/rss$ thufir@ARRAKIS:~/projects/rss$ ruby user2.rb user2.rb:5: undefined method `' for nil:NilClass (NoMethodError) thufir@ARRAKIS:~/projects/rss$ thufir@ARRAKIS:~/projects/rss$ nl user.rb      1 require 'yaml'              2 yml = YAML::load(File.open('user.yml'))              3 yml.each_key { |key|      4 username = yml[key]['user']      5 password = yml[key]['pass']              6 puts "#{username} => #{password}"      7 } thufir@ARRAKIS:~/projects/rss$ thufir@ARRAKIS:~/projects/rss$ nl user2.rb      1 require 'yaml'              2 yml = YAML::load(File.open('user.yml'))              3 username = yml['juixe']['user']              4 puts username thufir@ARRAKIS:~/projects/rss$ thufir@ARRAKIS:~/projects/rss$ nl user.yml      1 juixe:      2 user: juixe-user      3 pass: juixe-pass              4 techknow:      5 user: techknow-user      6 pass: techknow-pass thufir@ARRAKIS:~/projects/rss$ thufir@ARRAKIS:~/projects/rss$

http://yaml.kwiki.org/index.cgi?YamlInFiveMinutesMinuteThree refers to this structure as a nested map, FWIW. In either event, how would you either iterate through the entire structure, or specify the "juixe" map (or node)?

thanks,

Thufir

2

Not sure if Groups has eaten the formatting or not - are lines 2, 3, 5 and 6 indented? The YAML won't work otherwise...

script/console (or irb if you're not in Rails) is helpful here; try doing a YAML.load_file(filename) there and see what you get back.

--Matt Jones

3

I use Gmane for this list, but, yeah, things somehow get mangled. No, they weren't indented. Works now:

thufir@ARRAKIS:~/projects/rss$ thufir@ARRAKIS:~/projects/rss$ thufir@ARRAKIS:~/projects/rss$ ruby user.rb techknow-user => techknow-pass juixe-user => juixe-pass thufir@ARRAKIS:~/projects/rss$ thufir@ARRAKIS:~/projects/rss$ nl user.yml      1 juixe:      2 user: juixe-user      3 pass: juixe-pass              4 techknow:      5 user: techknow-user      6 pass: techknow-pass thufir@ARRAKIS:~/projects/rss$

thanks,

Thufir