How to map a Ruby hash?

Question

Is there a better way to map a Ruby hash? I want to iterate over each pair and collect the values. Perhaps using tap?

hash = { a:1, b:2 } output = hash.to_a.map do |one_pair| k = one_pair.first v = one_pair.last "#{ k }=#{ v*2 }" end >> [ [0] "a=2", [1] "b=4" ]

Dan Grahn · Accepted Answer · 2013-12-02 19:05:47Z

Ruby's hash includes the Enumerable module which includes the map function.

hash = {a:1, b:2} hash.map { |k, v| "#{k}=#{v * 2}" }

user229044 · Accepted Answer · 2013-12-02 18:58:44Z

Err, yes, with map, invoked directly on the hash:

{ a:1, b:2 }.map { |k,v| "#{k}=#{v*2}" } # => [ 'a=2', 'b=4' ]

Arup Rakshit · Accepted Answer · 2013-12-02 18:58:58Z

1

hash = { a:1, b:2 } hash.map{|k,v| [k,v*2]* '='} # => ["a=2", "b=4"]

answered Dec 2, 2013 at 18:58

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