A Clash is a "Chainable Lazy Hash". Inspired by libraries such as Arel, a Clash allows you to chain together method arguments to build a hash, something that‘s especially useful if you‘re doing something like constructing a complex options hash. Here‘s a basic example:

    c = Hashie::Clash.new.conditions(:foo => 'bar').order(:created_at)
    c # => {:conditions => {:foo => 'bar'}, :order => :created_at}

Clash provides another way to create sub-hashes by using bang notation. You can dive into a sub-hash by providing a key with a bang and dive back out again with the _end! method. Example:

    c = Hashie::Clash.new.conditions!.foo('bar').baz(123)._end!.order(:created_at)
    c # => { conditions: { foo: 'bar', baz: 123 }, order: :created_at}

Because the primary functionality of Clash is to build options objects, all keys are converted to symbols since many libraries expect symbols explicitly for keys.