Ruby - Hash#fetch

2015-03-14

If you can’t be bothered to set a default on a hash, you can always use Hash#fetch to specify a default as you go.

These are the examples from the docs

h = { "a" => 100, "b" => 200 }
h.fetch("a")                            #=> 100
h.fetch("z", "go fish")                 #=> "go fish"
h.fetch("z") { |el| "go fish, #{el}"}   #=> "go fish, z"

I usually think it’s safer to use this rather than Hash#[] (which is just usuing the normal hash[:possibly_doesnt_exist] syntax), as it removes the chances of a rogue nil popping up.

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