How do I search within an array of hashes by hash values in ruby?

ghz 1years ago ⋅ 4543 views

Question

I have an array of hashes, @fathers.

a_father = { "father" => "Bob", "age" =>  40 }
@fathers << a_father
a_father = { "father" => "David", "age" =>  32 }
@fathers << a_father
a_father = { "father" => "Batman", "age" =>  50 }
@fathers << a_father 

How can I search this array and return an array of hashes for which a block returns true?

For example:

@fathers.some_method("age" > 35) #=> array containing the hashes of bob and batman

Thanks.


Answer

You're looking for [Enumerable#select](https://ruby- doc.org/core-2.7.0/Enumerable.html#method-i-select) (also called find_all):

@fathers.select {|father| father["age"] > 35 }
# => [ { "age" => 40, "father" => "Bob" },
#      { "age" => 50, "father" => "Batman" } ]

Per the documentation, it "returns an array containing all elements of [the enumerable, in this case @fathers] for which block is not false."