Class: Super::Useful::Enum::Case

Inherits:
Object
  • Object
show all
Defined in:
lib/super/useful/enum.rb

Instance Method Summary collapse

Constructor Details

#initialize(choices, chosen) ⇒ Case

Returns a new instance of Case.



15
16
17
18
19
20
21
22
23
24
 
# File 'lib/super/useful/enum.rb', line 15

def initialize(choices, chosen)
  if !choices.key?(chosen)
    raise Error::Enum::ImpossibleValue,
      "`#{chosen}` isn't in: #{choices.keys.map(&:inspect).join(", ")}"
  end

  @choices = choices
  @chosen = chosen
  @whens = {}
end

Instance Method Details

#result ⇒ Object 



42
43
44
45
46
47
48
49
 
# File 'lib/super/useful/enum.rb', line 42

def result
  if @choices.size != @whens.size
    missing_keys = @choices.keys - @whens.keys
    raise Error::Enum::UndefinedCase, "Unset cases: #{missing_keys.join(", ")}"
  end

  @whens[@chosen].call(@value)
end

#when(*keys, &block) ⇒ Object 



26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
 
# File 'lib/super/useful/enum.rb', line 26

def when(*keys, &block)
  if !block
    raise Error::ArgumentError, "must receive block"
  end

  keys.each do |key|
    if !@choices.key?(key)
      raise Error::Enum::ImpossibleValue, "`#{key.inspect}` is not a possibility"
    end

    @whens[key] = block
  end

  self
end