class ParseOpt

Public Class Methods

new(usage = nil) { |self| ... } click to toggle source

Creates a new instance.

Yields itself if called with a block.

@param [String] usage usage banner.

@yieldparam [ParseOpt] self Option parser object

# File lib/parseopt.rb, line 25
def initialize(usage = nil)
  @list = {}
  @usage = usage
  yield self if block_given?
end

Public Instance Methods

on(short, long = nil, help = nil, &block) click to toggle source

Creates an option.

The block is called with the value when the option is found.

@example Simple boolean

opts.on('b') { $bool = true }

@example Simple string with value

opts.on('s', 'string') { |value| $string = value }

@yieldparam value value parsed

# File lib/parseopt.rb, line 41
def on(short, long = nil, help = nil, &block)
  opt = Option.new(short, long, help, &block)
  @list[short] = opt if short
  @list[long] = opt if long
end

parse(args = ARGV) click to toggle source

Parses all the command line arguments

# File lib/parseopt.rb, line 48
def parse(args = ARGV)
  if args.member?('-h') or args.member?('--help')
    usage
    exit 0
  end
  seen_dash = false
  args.delete_if do |cur|
    opt = val = nil
    next false if cur[0] != '-' or seen_dash
    case cur
    when '--'
      seen_dash = true
      next true
    when /^--no-(.+)$/
      opt = @list[$1]
      val = false
    when /^-([^-])(.+)?$/, /^--(.+?)(?:=(.+))?$/
      opt = @list[$1]
      val = $2 || true
    end
    opt&.call(val)
  end
end

usage() click to toggle source

Generates the usage output (similar to `–help`)

# File lib/parseopt.rb, line 78
def usage
  puts 'usage: %s' % @usage
  @list.values.uniq.each do |opt|
    s = '    '
    s << ''
    s << [opt.short&.prepend('-'), opt.long&.prepend('--')].compact.join(', ')
    s << ''
    s << '%*s%s' % [26 - s.size, '', opt.help] if opt.help
    puts s
  end
end

usage=(value) click to toggle source

Sets the usage banner

# File lib/parseopt.rb, line 73
def usage=(value)
  @usage = value
end