Is there an opposite function of slice function in Ruby?

Question

In this post, slice function is used to get only necessary elements of params. What would be the function I should use to exclude an element of params (such as user_id)?

Article.new(params[:article].slice(:title, :body)) 

Thank you.

Answer 1

Use except:

a = {"foo" => 0, "bar" => 42, "baz" => 1024 } a.except("foo") # returns => {"bar" => 42, "baz" => 1024} 

Answer 2

Inspired in the sourcecode of except in Rails' ActiveSupport

You can do the same without requiring active_support/core_ext/hash/except

    # h.slice( * h.keys - [k1, k2...] )      # Example:     h = { a: 1, b: 2, c: 3, d: 4 }     h.slice( * h.keys - [:b, :c] ) # => { a: 1, d: 4}