module OptParseBuilder

The namespace of this library, and the sole entry point. You never have to (and never should) explicitly refer to any other class or module of this library than this one. There are a few other classes you will use, but they will be created for you by methods of this module.

Minimal example:

arg_parser = OptParseBuilder.build_parser
arg_parser.parse!

An example with a little bit of everything

arg_parser = OptParseBuilder.build_parser do |p|
  parser.banner "A short description of the program"
  parser.add do |arg|
    arg.key :output_path
    arg.required_operand
  end
  parser.add do |arg|
    arg.key :input_paths
    arg.splat_operand
  end
  parser.add do |arg|
    arg.key :quiet
    arg.on "-q", "--quiet", "Be quiet"
  end
  parser.add do |arg|
    arg.key :size
    arg.default 1024
    arg.on "--size=N", Integer
    arg.on "Size in bytes (default _DEFAULT_)"
  end
  parser.separator "Explanatory text at the bottom"
end
arg_values = arg_parser.parse!
p arg_values.quiet          # nil or true
p arg_values.size           # An Integer
p arg_values.output_path    # A string
p arg_values.input_paths    # An array of strings

Constants

VERSION: Library version. Follows Semantic Versioning 2.0

Public Class Methods

build_argument() { |builder| ... } click to toggle source

Build an argument that can be added to a parser. Yields an ArgumentBuilder. Returns the argument created by the builder.

VERBOSE = OptParseBuilder.build_argument do |arg|
  arg.key :verbose
  arg.on "-v", "--verbose", "Print extra output"
end

arg_parser = OptParseBuilder.build_parser do |args|
  args.add VERBOSE
end

See the README for argument examples.

Raises BuildError if the argument cannot be built or added.

This is most useful when you are building a related suite of programs that share some command-line arguments in common. Most of the time you will just add the argument using the block form of OptParseBuilder#add.

# File lib/opt_parse_builder.rb, line 117
def self.build_argument
  builder = ArgumentBuilder.new
  yield builder
  builder.argument
end

build_bundle() { |bundler| ... } click to toggle source

Build a bundle of arguments that can be added to a parser together. Yields an ArgumentBundleBuilder.

This is useful when you have a group of arguments that go together:

bundle = OptParseBuilder.build_bundle do |args|
  args.add do |arg|
    arg.key :x
    op.on "-x", Integer, "X coordinate"
  end
  args.add do |arg|
    arg.key :y
    op.on "-y", Integer, "Y coordinate"
  end
end

arg_parser = OptParseBuilder.build_parser do |args|
  args.add bundle
end

Raises BuildError if the argument cannot be built or added.

This is most useful when you are building a related suite of programs that share some command-line arguments in common. Most of the time you will just add the arguments using the block form of OptParseBuilder#add.

# File lib/opt_parse_builder.rb, line 150
def self.build_bundle
  bundler = ArgumentBundleBuilder.new
  yield bundler
  bundler.argument
end

build_parser() { |parser_builder| ... } click to toggle source

Create a new parser. If called without a block, returns a parser than you can then add arguments to:

arg_parser = OptParseBuilder.build_parser
arg_parser.add do |arg|
  arg.key :force
  arg.on "--force", "Force dangerous operation"
end

If called with a block, yields itself to the block:

arg_parser = OptParseBuilder.build_parser do |args|
  args.add do |arg|
    arg.key :force
    arg.on "--force", "Force dangerous operation"
  end
end

Note that the parser constructed using the block form can still be added onto:

arg_parser.add do |arg|
  arg.key :size
  arg.on "--size=N", Integer, "File size in bytes"
end

# File lib/opt_parse_builder.rb, line 91
def self.build_parser
  parser_builder = ParserBuilder.new
  yield parser_builder if block_given?
  parser_builder.parser
end