How do I convert a word to phonetic alphabet in Ruby? - ruby

Question

I am trying write a code to convert a word into phonetic alphabet. The desired return value should be something like this:
# >> Type your name and I will convert it to Phonetic Alphabets!
Kevin
# >> Kilo Echo Victor India November
I wrote a hash.
puts "Type your name and I will convert it to Phonetic Alphabets!"
name = gets.chomp
nato_keys = {
"A": "Alpha", "B": "Bravo", "C": "Charlie",
"D": "Delta", "E": "Echo", "F": "Foxtrot",
"G": "Golf", "H": "Hotel", "I": "India",
"J": "Juliett","K": "Kilo", "L": "Lima",
"M": "Mike", "N": "November","O": "Oscar",
"P": "Papa", "Q": "Quebec", "R": "Romeo",
"S": "Sierra", "T": "Tango", "U": "Uniform",
"V": "Victor", "W": "Whiskey", "X": "X-ray",
"Y": "Yankee", "Z": "Zulu"
}
def nato()
puts name.nato_keys.upcase().join(" ")
end
I have an issue with my method as it triggers an error.

Answer 1

Since no one mentioned it, here's a solution with values_at (this assumes string keys in the substitutions hash, as they should be).
str = "Kevin"
nato_keys.values_at(*str.upcase.chars).join(' ')

Answer 2

Assuming the number of words to converted is more than 26 it makes sense to prepare the appropriate hash before doing any conversions.
H = nato_keys.transform_keys(&:to_s)
#=> {"A"=>"Alpha", "B"=>"Bravo",..., "Z"=>"Zulu"}
word = gets.chomp
Supose
word = "Kevin"
Then
word.upcase.each_char.map { |c| H[c] }.join(' ')
#=> "Kilo Echo Victor India November"

Answer 3

You would want to do this:
name.chars.map { |x| nato_keys[x.upcase.to_sym] }.join(' ')
This name.chars give the enumeration with each character of the string name, map iterates on each character and transforms it to the instruction in the block.
block { |x| nato_keys[x.upcase.to_sym] }, picks the relevant mapping for the character, but before that, it converts the key to uppercase and symbol(because in your nato_keys, keys are symbols). 'a' will become :A.
After the block manipulation, we join the result with ' ' to give resultant string.

Answer 4

name.upcase.chars.map(&:intern).map(&nato_keys).join(' ')
First we upcase the entire string. We then split the string into each individual char and turn each into a symbol. Then we can map over the chars sending them one at a time to the nato_keys element reference [], returning the phonetic word, and converting the name. Finally, join them with spaces to format the new string.
EDIT: When using Hash element references we can call the Hash itself.

Answer 5

As Cary Swoveland says, the hash nato_keys, which really does not make sense, has to be converted to one that makes sense:
nato_keys.transform_keys!(&:to_s)
Given:
name = "Kevin"
then,
name.gsub(/(\A)?./){"#{" " unless $1}#{nato_keys[$&.upcase]}"}
# => "Kilo Echo Victor India November"

Answer 6

I would start with preparing more robust hash to transform
transform =
nato_keys.
flat_map do |k, v|
v = v + ' '
[[k.to_s, v], [k.to_s.downcase, v]]
end.
to_h.
tap { |h| h.default_proc = ->(h, k) { h[k] = k } }
Now you might transform your words as easy as:
"Kevin".gsub(/./, transform).strip
#⇒ "Kilo Echo Victor India November"