Class: LilUtils::CLI::OptionList

Inherits:
Object
  • Object
show all
Defined in:
lib/lilutils/cli/cli.rb

Overview

Models a generic list of options that determines if a particular key results in valid response. Takes care of generic behavior (display, validity of user response, defaults) when a list of options is presented to the user.

Direct Known Subclasses

NumberedOptions, YesNo, YesNoCancel

Constant Summary collapse

DEFAULT_PROMPT = 
"Do you want to proceed?"

Instance Method Summary collapse

Constructor Details

#initialize(options, default_option_index, prompt, strict, istream = $stdin, ostream = $stdout) ⇒ OptionList

Returns a new instance of OptionList.



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# File 'lib/lilutils/cli/cli.rb', line 127

def initialize(options, default_option_index, prompt, strict, istream=$stdin, ostream=$stdout)
  # check, list must be non-nil and must have at least two elements
  @options        = options
  @default_option = options[default_option_index]
  @prompt         = prompt
  @strict         = strict
  @istream        = istream
  @ostream        = ostream
end

Instance Method Details

#debug(str) ⇒ Object 



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# File 'lib/lilutils/cli/cli.rb', line 176

def debug(str)
  puts "debug: #{str}" if $DEBUG
end

#display_string ⇒ Object

subclasses may override, but don’t have to



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# File 'lib/lilutils/cli/cli.rb', line 146

def display_string
  long_str = ""
  @options.each_with_index do |option, index|
    if option == @default_option
      long_str << option.as_default
    else
      long_str << option.as_non_default
    end
    long_str << "/" if index < (@options.size-1)
  end
  "#{@prompt} [#{long_str}] "
end

#show ⇒ Object

the whole point is subclasses get this for free



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# File 'lib/lilutils/cli/cli.rb', line 160

def show
  @ostream.print "#{display_string}"
  response = @istream.gets.chomp!
  chosen   = valid_response? response
  if @strict
    until chosen
      @ostream.print "\nSorry, I don't understand #{response}, #{display_string}"
      response = @istream.gets.chomp!
      chosen   = valid_response? response
    end
  else
    chosen = @default_option # when not strict, any key => default option
  end
  chosen
end

#valid_response?(r) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/lilutils/cli/cli.rb', line 137

def valid_response?(r)
  @options.each do |option|
    debug "#{option} == #{@default_option} ? : (#{option == @default_option})"
    return option if (option == @default_option && r == "") || (option.valid_response(r))
  end
  nil
end