[ruby-core:71397] [Ruby trunk - Feature #11643] A new method on Hash to grab values out of nested hashes, failing gracefully

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Issue #11643 has been updated by Yukihiro Matsumoto. The idea is accepted. The name is the problem. The current candidates are 'dig' and 'fetch_in'. I prefer 'dig'. If you have any other idea, please propose. Matz. ---------------------------------------- Feature #11643: A new method on Hash to grab values out of nested hashes, failing gracefully https://bugs.ruby-lang.org/issues/11643#change-54766 * Author: Gabe Kopley * Status: Open * Priority: Normal * Assignee: ---------------------------------------- (I posted this to the mailing list last year [0] and received no response, but am inspired to file an issue here based on the positive reception to https://bugs.ruby-lang.org/issues/11537 ) This comes up sometimes in Rails programming [1]: `params[:order] && params[:order][:shipping_info] && params[:order][:shipping_info][:country]` or `params[:order][:shipping_info][:country] rescue nil` or `params.fetch(:order, {}).fetch(:shipping_info, {}).fetch(:country, nil)` What if Hash gave us a method to accomplish this more concisely and semantically? Eg. `params.traverse_nested_hashes_and_return_nil_if_a_key_isnt_found(:order, :shipping_info, :country)` Or to take a nice method name suggestion [2]: `params.dig(:order, :shipping_info, :country)` Another example solution is https://github.com/intridea/hashie#deepfetch (Although I don't like "fetch" in this method name since it doesn't and can't take a default value as an argument like Hash#fetch does) What do you all think? [0] https://groups.google.com/forum/#!topic/ruby-core-google/guleNgEJWcM [1] https://groups.google.com/d/msg/rubyonrails-core/bOkvcvS3t_A/QXLEXwt9ivAJ https://stackoverflow.com/questions/1820451/ruby-style-how-to-check-whether-a-nested-hash-element-exists https://stackoverflow.com/questions/19115838/how-do-i-use-the-fetch-method-for-nested-hash https://stackoverflow.com/questions/10130726/ruby-access-multidimensional-hash-and-avoid-access-nil-object [2] http://stackoverflow.com/a/1820492/283398 -- https://bugs.ruby-lang.org/