How to add more than one piece of data to an array follow the .each method

Question

I have the following method:

def speciate 
  chem_formula.each { |chemical|
    @chem_species = chemical.scan(/[A-Z][^A-Z]*/)
    puts @chem_species
  }
end

that produces:

H2
S
O4

@chem_species = ["S", "O4"]

from: @chem_formula = ["H2" "SO4"]

How do you set the array to include all iterations? That is how do you output ["H2", "S", "O4"] rather than ["S", "O4"] Thank you in advance.

Answer 1

Not the most elegant as you're building an array then flattening but this works:

@chem_formula.map{|chem| chem.scan(/[A-Z][^A-Z]*/) }.flatten

Answer 2

def speciate
  @chem_species = []
  chem_formula.each { |chemical|
    @chem_species.concat(chemical.scan(/[A-Z][^A-Z]*/))
    puts @chem_species
  }
end

Answer 3

An elegant way is:

@chem_formula.flat_map{|chem| chem.scan(/[A-Z][^A-Z]*/) }

Note: flat_map is new to Ruby 1.9.2. Either ugrade, require 'backports' or use map{}.flatten if using an older Ruby.