Class: Samovar::ValueFlag

Inherits:
Flag
  • Object
show all
Defined in:
lib/samovar/flags.rb

Overview

Represents a flag that accepts a value or acts as a boolean.

Instance Attribute Summary collapse

Attributes inherited from Flag

#prefix, #text

Instance Method Summary collapse

Methods inherited from Flag

#key, parse, #to_s

Constructor Details

#initialize(text, prefix, value) ⇒ ValueFlag

Initialize a new value flag.



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# File 'lib/samovar/flags.rb', line 144

def initialize(text, prefix, value)
  super(text, prefix)
  
  @value = value
  
  *@alternatives, @prefix = @prefix.split("/")
end

Instance Attribute Details

#alternatives ⇒ Object (readonly)

Alternative flag prefixes.



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# File 'lib/samovar/flags.rb', line 155

def alternatives
  @alternatives
end

#value ⇒ Object (readonly)

The value placeholder.



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# File 'lib/samovar/flags.rb', line 160

def value
  @value
end

Instance Method Details

#boolean? ⇒ Boolean

Whether this is a boolean flag (no value required).



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# File 'lib/samovar/flags.rb', line 165

def boolean?
  @value.nil?
end

#parse(input) ⇒ Object

Parse this flag from the input.



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# File 'lib/samovar/flags.rb', line 181

def parse(input)
  if prefix?(input.first)
    # Whether we are expecting to parse a value from input:
    if @value
      # Get the actual value from input:
      flag, value = input.shift(2)
      return value
    else
      # Otherwise, we are just a boolean flag:
      input.shift
      return key
    end
  end
end

#prefix?(token) ⇒ Boolean

Check if the token matches this flag.



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# File 'lib/samovar/flags.rb', line 173

def prefix?(token)
  @prefix == token or @alternatives.include?(token)
end