How can I filter a hash from an array of symbols? [duplicate]

Question

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Hash remove all except specific keys (7 answers)

Closed 8 years ago.

So I have a hash that I would like to filter based on an array:

h = {a: 'test1', b: 'test2', c: 'test3'}
a = [:a, :poo1, :poo2]

My first thought was to try:

h.slice(a)

But that returns {}, when I hoped it would return {:a=>"test1"}. I can't seem to find a simple way of filtering my hash based on an array of symbols. Thoughts?

Answer 1

You can solve this by using the splat operator:

h.slice(*a)

This will produce

> {:a=>"test1"}

For an explanation what the asterisk does, please see this link.