function
boot.janet on line 1820 , column 1
(get-in x ks &opt dflt )
Use the keys `ks` to look up a nested value in `x` . If a value is
not found , will return `dflt` if provided , or `nil` otherwise.
`x` can be a suitable indexed , dictionary , or abstract type with a
`get` method.
`ks` can be an indexed or abstract type with `get` and `next`
methods.
(get-in {:a {:cc 2 } :b {:dd 3 }} [:a ] 42 ) # => {:cc 2}
(get-in {:a {:cc 2 } :b {:dd 3 }} [:a :cc ] 42 ) # => 2
(get-in {:a {:cc 2 } :b {:dd 3 }} [0 ] 42 ) # => 42
(get-in {:a {:cc 2 } :b {:dd 3 }} [:z ] 42 ) # => 42
(get-in [[4 5 ] [6 7 ]] [0 ] 42 ) # => (4 5)
(get-in [[4 5 ] [6 7 ]] [0 1 ] 42 ) # => 5
(get-in [[4 5 ] [6 7 ]] [-1 ] 42 ) # => 42
(get-in [[4 5 ] [6 7 ]] [9 9 9 ] 42 ) # => 42
(def request {:params {:id 1 }}) # => {:params {:id 1}}
(get-in request [:params :id ]) # => 1
(get-in request [:params :name ]) # => nil
(get-in request [:params :name ] "N/A" ) # => "N/A"