Safe navigation equivalent to Rails try for hashes
&.
is not equivalent to Rails' try
, but you can use &.
for hashes. Just use it, nothing special.
hash[:key1]&.[](:key2)&.[](:key3)
Although I would not do that.
Ruby 2.3 and later
There's Hash#dig
method now that does just that:
Retrieves the value object corresponding to the each key objects repeatedly.
h = { foo: {bar: {baz: 1}}}
h.dig(:foo, :bar, :baz) #=> 1
h.dig(:foo, :zot) #=> nil
http://ruby-doc.org/core-2.3.0_preview1/Hash.html#method-i-dig
Pre Ruby 2.3
I usually had something like this put into my intializer:
Class Hash
def deep_fetch *args
x = self
args.each do |arg|
x = x[arg]
return nil if x.nil?
end
x
end
end
and then
response.deep_fetch 'PaReqCreationResponse', 'ThreeDSecureVERes', 'Message', 'VERes', 'CH', 'enrolled'
in one wacky case.
The general consensus in the community seems to be to avoid both try and the lonely operator &.